# Cayin HA-6A Class A KT88/EL34 Tube Headphone Amplifier



## Andykong (Nov 15, 2019)

Its EL34 based but you can use KT88 as well.
More detail will be available next week, but if you are attending Canjam Shanghai and want to preview this, the Cayin HA-6A is pairing with Empyrean at Meze booth (B7-B9).


----------



## Andykong

Reserved


----------



## Andykong (Nov 13, 2019)




----------



## dadracer2

Andykong said:


>



Yes, i just saw the photo on the Cayin FB page. It looks delightful. How soon before you can post some details such as the specifications and price? I think I would choose the KT88 version of the 2 as the valves are more sculptural than the EL34s.


----------



## llamaluv

Would someone like to hazard a general characterization of the "sound" of EL34s vs KT88s and even vs 300Bs?


----------



## dadracer2

llamaluv said:


> Would someone like to hazard a general characterization of the "sound" of EL34s vs KT88s and even vs 300Bs?


I think it is so dependent on the implementation of those valves and what manufacture and what transformers and wiring and feedback and are they in ultra linear or triode and so on. Unless you define the parameters that's an impossible question to answer meaningfully.


----------



## llamaluv (Nov 13, 2019)

Makes sense. I've been eyeing the HA-300 for some time now so will be very curious to find out how this new Cayin amp compares or differs.

I'm sure one thing we can assume in advance is that switching between the two tube types will result in meaningfully different types of presentation.


----------



## dadracer2

llamaluv said:


> Makes sense. I've been eyeing the HA-300 for some time now so will be very curious to find out how this new Cayin amp compares or differs.
> 
> I'm sure one thing we can assume in advance is that switching between the two tube types will result in meaningfully different types of presentation.


I would think so, but without knowing a wee bit more on the specs it would be just be guessing. The HA 300 is a truly joyful amp and should be the amp of choice for most high end planars and definitively the HD800S. It will be interesting to see how the new amp performs compared to the HA 300. Of course you might even prefer the sound of the new amp depending on what aspects of sound matter to you the most. It would certainly be worth comparing them to see which you like better before you spend all that money!


----------



## Andykong

dadracer2 said:


> Yes, i just saw the photo on the Cayin FB page. It looks delightful. How soon before you can post some details such as the specifications and price? I think I would choose the KT88 version of the 2 as the valves are more sculptural than the EL34s.



I had compared the late prototype of EL34 and KT88 version of HA-6a side by side last month, my general observation is KT88 for full size planar and really low sensitivity cans and EL34 for most dynamics and planar with easier sensitivity. These are "general" observation but this will also affected by music genre and the your personal preference.

But wait, why do you need to "choose" a version?  You can buy a HA-6A and swap between EL34 and KT88 anytime you like.


----------



## Andykong (Nov 15, 2019)

dadracer2 said:


> I think it is so dependent on the implementation of those valves and what manufacture and what transformers and wiring and feedback and are they in ultra linear or triode and so on. Unless you define the parameters that's an impossible question to answer meaningfully.



Just to let the readers know that the HA-6A offers both triode and ultra-linear mode and user and select the mode without turning off the amplifier.  We have these option with our better speaker based amplifiers and this is the first time we "migrate" the technologies to Personal Audio product line. To the best of our knowledge, this is the first ever tube headphone amplifier offers triode and ultra-linear mode selection, if you know of any previous product equipped with similar features, please let us know and we'll be most delighted to explore the pros and cons of different implementations.

I have added a new poster to highlight this feature in post #1.


----------



## Andykong

llamaluv said:


> Makes sense. I've been eyeing the HA-300 for some time now so will be very curious to find out how this new Cayin amp compares or differs.
> 
> I'm sure one thing we can assume in advance is that switching between the two tube types will result in meaningfully different types of presentation.



Actually more then that.

When switch the HA-6A to KT88 mode, you can use KT88 variants including KT100, KT90, 6550, 6550A, 6550EH vacuum tubes.  When you switch it to EL34 mode, you can also use EL37, 6CA7, 6L6GC, 5881, KT77 and KT66.

Together with Triode and  Ultra-linear dual mode selection, the HA-6A offers a lot of sound signature options in one compact chassis.


----------



## yerim

How about the price of this? Any estimated price yet?


----------



## Andykong

yerim said:


> How about the price of this? Any estimated price yet?



Safe to say this is around the middle point between HA-1Amk2 and HA-300.  We shall announced the price and package very soon.


----------



## musicman59

My PrimaLuna Dialogue Premium HP has the feature to change between Triode and Ultralinear on the fly. It is an integrated amp with headphones output same as the speakers output just reducing the power to fit headphones.
I actually use it exclusively for headphones.
It can also un EL34, EL77, KT88, KT120 and KT150.


----------



## dadracer2

Andykong said:


> Safe to say this is around the middle point between HA-1Amk2 and HA-300.  We shall announced the price and package very soon.


Can you post a photo of the rear please? Just wondering if there will be speaker posts...........


----------



## dpump

What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?


----------



## dadracer2

dpump said:


> What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?


I think they could be power supply rectifiers and maybe are the RCA 22DE4, which is the one used on the HA300 for the same purpose.


----------



## Matro5

Very curious to see if this might also be used an amp, or a preamp...


----------



## 340519

Andykong said:


>


It looks beautiful.


----------



## whirlwind

This has my attention.


----------



## Andykong

Matro5 said:


> Very curious to see if this might also be used an amp, or a preamp...



No speaker out or RCA/XLR output, straight forward headphone amplifier only.


----------



## Andykong

dpump said:


> What are 2 tubes on the left side? Maybe voltage regulators? And the 2 input tubes? 12AU7 or something else?



Very good eyes, the input tubes are 12AU7.  The two rectifier tubes on the left are 22DE4


----------



## Andykong

dadracer2 said:


> I think they could be power supply rectifiers and maybe are the RCA 22DE4, which is the one used on the HA300 for the same purpose.



Indeed, the HA-6A incurred a lot of elements from HA-300, you can even consider the chassis as a one-box scale-down version of HA-300, with the separated power supply merged with the amplifier chassis and then scaled down from 445mm (159 mm + 286mm in HA-300) to the current 360mm


----------



## Andykong

musicman59 said:


> My PrimaLuna Dialogue Premium HP has the feature to change between Triode and Ultralinear on the fly. It is an integrated amp with headphones output same as the speakers output just reducing the power to fit headphones.
> I actually use it exclusively for headphones.
> It can also un EL34, EL77, KT88, KT120 and KT150.



But the Triode and Ultralinear mode only apply to the speaker output, the headphone output of the Dialogue Premium HP is not coming from the EL34 output, so not affected by the mode selection.


----------



## Andykong

dadracer2 said:


> Can you post a photo of the rear please? Just wondering if there will be speaker posts...........



I don't have a photo of the rear panel, but the following drawing should serve the purpose.  There is no speaker output in the HA-6A.


----------



## musicman59

Do you own one? Have you listen to it and trying switching?
The headphones output is coming from the EL34 output. That’s the reason I bought it and use it as a tube headphones amplifier.
You can very clear hear out of the headphones the change in sound when you switch between the two modes.


----------



## musicman59

From the PrimaLuna website:
*HEADPHONE AMPLIFIER*
*One of the best headphone amps in the world.* *And the only amp that lets you listen with either the warmth of Triode or the wide-bandwidth of Ultra-linear operation at the push of a button! *Most tube integrated amps and preamps use a solid state op-amp chip for running headphones. Stand alone tube headphone amps will vary in quality like any other tube amp. *Headphones are simply small speakers that require less power.* Some amps will use smaller output tubes that groan to have enough dissipation to run power-hungry planar headphones. Other brands, including those costing $5,000 or more like Mal Valve, will use larger output tubes, then use a voltage divider network to drop the power down to an acceptable level for headphones. This is how PrimaLuna designed the HP. *We simply took advantage of the fact that this is the best tube integrated amplifier.* Now you don't have to pay for a separate state of the art headphone amp. The HP is the favorite of owners who use everything from Audeze to Hifiman to Sennheiser!

and as I said, one can clearly hear the difference through the headphones when switching between Triode and Ultralinera.


----------



## dadracer2

Andykong said:


> I don't have a photo of the rear panel, but the following drawing should serve the purpose.  There is no speaker output in the HA-6A.


Thanks Andy. Shame about the speaker outs but I can see the strong family resemblance with the HA300.


----------



## 441879

Sign me up. I’ve been looking at the HA-1A an HA-300 for a while now and this looks like what I’m seeking.


----------



## Andykong

musicman59 said:


> From the PrimaLuna website:
> *HEADPHONE AMPLIFIER*
> *One of the best headphone amps in the world.* *And the only amp that lets you listen with either the warmth of Triode or the wide-bandwidth of Ultra-linear operation at the push of a button! *Most tube integrated amps and preamps use a solid state op-amp chip for running headphones. Stand alone tube headphone amps will vary in quality like any other tube amp. *Headphones are simply small speakers that require less power.* Some amps will use smaller output tubes that groan to have enough dissipation to run power-hungry planar headphones. Other brands, including those costing $5,000 or more like Mal Valve, will use larger output tubes, then use a voltage divider network to drop the power down to an acceptable level for headphones. This is how PrimaLuna designed the HP. *We simply took advantage of the fact that this is the best tube integrated amplifier.* Now you don't have to pay for a separate state of the art headphone amp. The HP is the favorite of owners who use everything from Audeze to Hifiman to Sennheiser!
> 
> and as I said, one can clearly hear the difference through the headphones when switching between Triode and Ultralinera.



I have consulted our Engineers regarding the TR and UL operation mode in more detail, and find out that Cayin MT-35MK2 and CS-55A (both EL34 version and KT88 version) are tube integrated amplifier with headphone output and TR/UL selection.  The headphone output of these two integrated amplifiers are an attenuated output from speaker port directly, so the TR/UL selection will also affect the headphone output, theoretically they are also headphone output with TR/UL selection.  However our Engineer consider these two integrated amplifier are speaker amplifiers primarily and the headphone output are not optimised other than attenuation, so they won't call these headphone amplifier technically, especially when compare to our HA-1A, HA-6A and HA-300 where we have impedance matching output to optimise the performance of headphone amplifier for wide range of headphones.  We can't tell if the PrimaLuna has a designated headphone amplifier circuit speaker amplification.   Maybe they have and that'll make them superior to the two examples I quoted.


----------



## 441879

@Andykong When do you think you might be able to post specs? Also, is there a unit circulating to some reviewers? I’m very interested in this amp, but would like to learn a bit more about it. I have no doubt it will sound great, but I’m an engineer so Specifications are important to me.

will


----------



## Andykong

> @Andykong When do you think you might be able to post specs? Also, is there a unit circulating to some reviewers? I’m very interested in this amp, but would like to learn a bit more about it. I have no doubt it will sound great, but I’m an engineer so Specifications are important to me.
> 
> will



Translation WIP, give me a week and I should be able to provide more technical information with specification.


----------



## Jandu (Nov 21, 2019)

Earlier version of Cayin KT 88 amps are good for switching between modes and tubes as well.


----------



## LTd head

Found some interesting news from China:
https://zx.ingping.com/c_2/54438.html

Try Google translate the page, if the link bellow will not work on your browser:
https://translate.google.com/translate?hl=en&sl=zh-CN&u=https://zx.ingping.com/c_2/54438.html

The retail price in China(!): 13,800 yuan. So 1,783.55 Euro or 1,963.32 USD. Without a doubt it will cost much more abroad.


----------



## 441879

LTd head said:


> Found some interesting news from China:
> https://zx.ingping.com/c_2/54438.html
> 
> Try Google translate the page, if the link bellow will not work on your browser:
> ...



thanks for digging this up!  $2K was about what I was expecting. Hopefully not much more or it’s big brother will steel sales.


----------



## Andykong

This is the Specification of HA-6A
The Power rating is a bit complicated because the choice of Power tube, phone out impedance and TR/UL mode will have an effect on output, so please be careful when you go through the numbers.


----------



## Andykong (Nov 29, 2019)

LTd head said:


> Found some interesting news from China:
> https://zx.ingping.com/c_2/54438.html
> 
> Try Google translate the page, if the link bellow will not work on your browser:
> ...



I said the HA-6A will be priced "round the middle point between HA-1Amk2 and HA-300" previously, that was a big hint on the suggested retail price.  

The suggested retail price of HA-6A  is US$ 2399.00.   The amplifier will be pre-installed with a matched pair of Genalex Gold Lion KT88, and we'll include a matched pair of Electro-Harmonix EL34 EH in the the HA-6A package.  In other word, you don't have to choose your prefer power tube, you own both options immediately and you can tube rolling as soon as you finish taking your open-box photo. 

The net weight of HA-6A is 19kg, so the shipping weight will be around 25kg.  No matter how carefully we packed up the tube amplifier,  there are still occasional damage report during the logistic process, almost inevitable for heavy tube amplifier like this.


----------



## ls13coco

Andykong said:


> I said the HA-6A will be priced "round the middle point between HA-1Amk2 and HA-300" previously, that was a big hint on the suggested retail price.
> 
> The suggested retail price of HA-6A  is US$ 2399.00.   The amplifier will be pre-installed with a matched pair of Genalex Gold Lion KT88, and we'll include a matched pair of Electro-Harmonix EL34 EH in the the HA-6A package.  In other word, you don't have to choose your prefer power tube, you own both options immediately and you can tube rolling as soon as you finish taking your open-box photo.
> 
> The net weight of HA-6A is 19kg, so the shipping weight will be around 25kg.  No matter how carefully we packed up the tube amplifier,  there are still occasional damage report during the logistic process, almost inevitable for heavy tube amplifier like this.



I am so looking forward to impressions vs the HA-300.
The 300 has been my goal for awhile, but cost savings in as beautiful of a design that may be even more versatile for headphones specifically is very appealing.


----------



## 441879

Andykong said:


> This is the Specification of HA-6A
> The Power rating is a bit complicated because the choice of Power tube, phone out impedance and TR/UL mode will have an effect on output, so please be careful when you go through the numbers.



Thanks for the specs. It’s a beast alright. Plenty of power for most headphones and enough weight to ensure at least a broken foot if you drop it.


----------



## Andykong

The HA-6A has incurred the proven amplification design of our HA-300.  The tube amplification part of the HA-6A is single-ended Class A, and then output from Power Tubes will feed into a pair of output transformer to provide genuine balanced driven output (both XLR4 and 4.4mm).  The single-ended RCA input will feed into the Tube Amplification section directly, but the Balanced XLR input go through a pair of input transformer and converted to single-ended.  The functional diagram of HA-6A will show the signal processing path clearly.  

 
So to clear the doubt.  Yes, the EL34 and KT88 are operated in Class A Single-ended, but the XLR4 and 4.4mm are truly balanced driver, they are NOT hard wired from single-ended phone out and they sound very different because of our Transformer coupled design.  Will single-ended tube amplification sounds good with balanced headphones?  Definitely if you implemented this correctly and Cay in HA-300 sustain this claim.   The design and quality of output transformer plays a very vital part in this approach and Cayin has a very unique advantages in this aspect: we are one of the very few, if not the only, headphone amplifier manufacturer that incorporate transformer design and production in-house.  We can design the transformers to meet the need of a specific amplifier, and wind the transformer in house exactly as design even when we are making high-end amplifier in small production batch. 

While finding an off-the-shelf transformer for speaker based amplifier is probably not very complicated because the loading and output features are quite homogenous.  However the output transformer of headphone amplifier are much more complicated as we need to take care of headphone loading from 8 ohm to 600 ohm, so being able to design and build transformer that meet the design of the headphone amplifier exactly is an significant consideration.


----------



## thecrow (Dec 20, 2019)

@Andykong let me raise my hands very high to show my interest if this 19.5kg amp is going to be doing a review tour (in Australia)

If you are thinking of one, i’m happy to give you full details of my gear at home which would work well for the meat/comparisons within a review that I would do

i guess the postage won’t be too cheap

just putting it out there


----------



## Faber65

I was one of the luckiest that had the chance to test it matched with the Meze Empyreans at the last Shanghai Canjam and I must say thank you to Mr. Andy for having allowed me to listen to that match as long as I wanted.
In my opinion it was one of the gears that during the show was totally overlooked.
I haven't seen anyone posting anything about that after the show.
Anyhow, that combo was an instant love for me...... simply superb!

I will take advantage of the coming Chinese New Year festival to visit the dealer in Shanghai to see how it works with my Focal Clear: I am seriously interested in that amp...

In case other local fellas are interested, the unit is available at the below dealer.

上海知音堂
Add: 上海市徐汇区南丹东路300弄9号亚都商务楼901～903 
Tel: 021-54233879
Contact:  余海


----------



## Doug2507

Any update on this being released to the general public @Andykong  ?


----------



## Faber65

Well, I am not Andy, but let me try to give you a rational answer.
The 24th we started the Chinese New Year holidays, so no local company would make any announcement before. 
Then almost the same day the Government started to take countermeasures against the nCoV and now the only thing that we know is that we (at least in my area) will start working on February 10.
So, realistically we won’t see any official announcement before that day.
In the meantime....... enjoy the music!


----------



## thecrow

it's on the website though isn't it - though not for sale through it.

you probably already know that


----------



## Faber65

thecrow said:


> it's on the website though isn't it - though not for sale through it.
> 
> you probably already know that


The Chinese website already shown the amplifier at the time of the CanJam in Shanghai.


----------



## Trickness (Jan 29, 2020)

Andykong said:


> I had compared the late prototype of EL34 and KT88 version of HA-6a side by side last month, my general observation is KT88 for full size planar and really low sensitivity cans and EL34 for most dynamics and planar with easier sensitivity. These are "general" observation but this will also affected by music genre and the your personal preference.
> 
> But wait, why do you need to "choose" a version?  You can buy a HA-6A and swap between EL34 and KT88 anytime you like.




On the surface, this product looks very much to be derived from the Primaluna Dialogue HP integrated amps which I believe are manufactured in the same facility - any thoughts on that Andy? I've got a Dialogue HP and to be honest I've never been particularly impressed by the headphone out despite that being one of the reasons I bought it. The headphone out lacks that last bit of transparency and liquidity one would hope for - by comparison I thought the HA-300 sounded glorious.


----------



## moosemp

Looks great indeed, for me it resembles Air Tight  amp, I wonder when it will  be  avaliable  in Europe.


----------



## OctavianH

Any review, impressions, unboxing? Has anyone tried it yet?


----------



## moosemp

I checked price inGermany- about 3500Euro......  In Poland they do not know neither when it will be avaliabe, nor the price.
Maybe I will buy HA 300 first...


----------



## moosemp

Andykong, I am going to visit Munich high end show this May , will Cayin be there with headphone amps???


----------



## Andykong

moosemp said:


> Andykong, I am going to visit Munich high end show this May , will Cayin be there with headphone amps???



Munich High-end is our major event, we plan to attend the show.  In fact we had a very attractive booth in 2019:
https://www.facebook.com/CayinAudio/posts/599787347099162?__tn__=-R

We hope the recent coronavirus outbreak will be contained by that and we can demonstrate the HA-6A in Munich as planned.


----------



## Andykong

Cayin will demonstrate our HA-6A in CanJam New York.



If you were attending the CanJam event tomorrow, make sure you drop by our booth (Managed by MusicTeck) and check out HA-6A. 

Our original plan is to deliver the HA-6A to our Europe and US dealers by April 2020, we are trying our best to keep that plan but we can't be 100% certain until we can resume full manufacturing operation in Zhuhai.


----------



## Andykong (Feb 14, 2020)

In case you want to check whether your desk has enough space for the HA-6A, this is a quite quite for you.  






If you have a highly revealing headphone and enjoy tube rolling, check out the options with HA-6A, I am sure you'll have a lot of fun.


----------



## OctavianH

You should make also a black version.


----------



## Relaxasaurus

Kicking myself I didn't hear this at Canjam today.


----------



## Stefanbat

Can someone write some impressions from canjam, how does it compare to HA-300 ?


----------



## Andykong

Stefanbat said:


> Can someone write some impressions from canjam, how does it compare to HA-300 ?



I saw HA-6A photo in CanJam NYC impression thread but no impression so far, maybe you have better luck if you raise this question there.


----------



## Articnoise

Andykong said:


> I saw HA-6A photo in CanJam NYC impression thread but no impression so far, maybe you have better luck if you raise this question there.



Does the Cayin HA-6A have faster transient response with less softening of the sound than the HA-300?


----------



## Relaxasaurus

I guess the biggest competitor to this amp at this price range is the Woo WA22 but the Cayin appears to have more versatility.


----------



## Faber65

We need to be patient. I guess that even now few companies already re-started the operations, the problem is the logistics. 
There is a whole economic and social flywheel to restart. 
So far the shop in Shanghai that have the sample in display is still closed.


----------



## Brooklyn70

Is this a balanced amp??


----------



## Faber65

Brooklyn70 said:


> Is this a balanced amp??


Yes, It is.


----------



## MSA1133

I was able to grab one from MusicTeck, though it will be a while until I'm able to review it properly as I'm traveling.


----------



## GU1DO

MSA1133 said:


> I was able to grab one from MusicTeck, though it will be a while until I'm able to review it properly as I'm traveling.


Cant wait for your thoughts about it ,, safe travel


----------



## Relaxasaurus

MSA1133 said:


> I was able to grab one from MusicTeck, though it will be a while until I'm able to review it properly as I'm traveling.


Perfect timing, Andrew just hand delivered this 40lb baby to my door, now that's service! Apparently it was the backup for the Canjam NYC.





I'll be doing a full unboxing and review on my new channel if you'd like to subscribe!

https://youtube.com/channel/UCaUIXGxXwxT9jpO-jxB72fg


----------



## Relaxasaurus

Really fun Sunday so far


----------



## GU1DO

Does this amp com in universal or single voltage 220v/110v ?


----------



## Relaxasaurus

Looks like single voltage.

Box:


Back of unit:


----------



## ls13coco

Relaxasaurus said:


> Really fun Sunday so far



Beautiful! I like how you are using it with the Arya now too, as that would be one of my pairings.


----------



## Relaxasaurus

Unboxing is up. My first video so be gentle :]



Trying to get my hands on some other headphones and/or equipment to see how it performs with different gear. If you're in the NYC area and want to either loan me or be in the review msg me.


----------



## GU1DO

Relaxasaurus said:


> Unboxing is up. My first video so be gentle :]
> 
> 
> 
> Trying to get my hands on some other headphones and/or equipment to see how it performs with different gear. If you're in the NYC area and want to either loan me or be in the review msg me.



Cant wait for the review , also i think i saw HD6XX , please include these in the review, it is one of the reasons i am exploring the tube realm


----------



## geoffalter11

Andykong said:


> Its EL34 based but you can use KT88 as well.
> More detail will be available next week, but if you are attending Canjam Shanghai and want to preview this, the Cayin HA-6A is pairing with Empyrean at Meze booth (B7-B9).


What a beauty.  Definitely on my radar.


----------



## Faber65

Available in the shops in China now!


----------



## Faber65

Articnoise said:


> Does the Cayin HA-6A have faster transient response with less softening of the sound than the HA-300?



I tested it at CanJam in Shanghai with the Meze Empyrean and to me it did sound amazing.
Quite good in micro and macro dynamics, deep bass, a little forward mids (as expected), but I don't know how much the final result had to be given to the cans, which are phenomenal to my ears, and the amp.
For sure that pairing was very very good.
I am just struggling to find an open shop where to go with my music, DAC and cans to test it better and decide whether to start saving money for it or not.....


----------



## Faber65

moosemp said:


> Andykong, I am going to visit Munich high end show this May , will Cayin be there with headphone amps???


https://www.whathifi.com/us/news/high-end-munich-2020-show-cancelled-due-to-coronavirus


----------



## Articnoise

Faber65 said:


> I tested it at CanJam in Shanghai with the Meze Empyrean and to me it did sound amazing.
> Quite good in micro and macro dynamics, deep bass, a little forward mids (as expected), but I don't know how much the final result had to be given to the cans, which are phenomenal to my ears, and the amp.
> For sure that pairing was very very good.
> I am just struggling to find an open shop where to go with my music, DAC and cans to test it better and decide whether to start saving money for it or not.....




I’m pleased to hear that you liked the Meze Empyrean driven by the Cayin HA-6A. I have listen to the Meze Empyrean on the HA-300 and didn’t like the paring, not even a little. To me the HA-300 matched much better together with Focal Utopia.

I love the look of the Cayin HA-6A and the price is quite a bit lower than the HA-300, which is too coloured and slow IMO. Do you know if the amp you listen to was switched to triode or ultra linear, and the sonic difference between the two?


----------



## Relaxasaurus (Mar 6, 2020)

My initial impressions:

*HFM Arya:*
Amp appears to be dead silent. Great build quality on the outside looks to be happening on the internals as well. That said with the planars I wasn't impressed to the level I was testing out other tube amps at Canjam. I liked what I was hearing but it wasn't like the feeling I experienced plugging the Aryas into an Auris Euterpe ($1700) and a Manley Absolute ($4500).

*Senn HD6XX:*
Wow! Now we're talking. The same near dead silence but with juicy tube amp goodness. Mids are pretty much perfect to my ears. What I'm hearing *really* makes me want to invest in an HD800.

Triode mode takes the edge off and sounds like a typical tube amp with rounded off edges. Ultra-linear mode sounds more like a solid state amp, more powerful, impactful, and details are retained up top. I'm glad both are there depending on the music you're listening to, but I generally prefer triode mode. I've been listening more & more making notes for the full review


----------



## OctavianH

Please continue to share your thoughts and also specify the rest of your setup. This product is, for sure, one of the most interesting new comers.


----------



## Faber65

Articnoise said:


> I’m pleased to hear that you liked the Meze Empyrean driven by the Cayin HA-6A. I have listen to the Meze Empyrean on the HA-300 and didn’t like the paring, not even a little. To me the HA-300 matched much better together with Focal Utopia.
> 
> I love the look of the Cayin HA-6A and the price is quite a bit lower than the HA-300, which is too coloured and slow IMO. Do you know if the amp you listen to was switched to triode or ultra linear, and the sonic difference between the two?



I don’t know the HA-300 so well or, at least, I don’t want to express an opinion without having listened the two amps in the same moment with the same headphones. 

What I can tell you is that the HA-6A is definitely not a laid back amp. Andy allowed me to play with the switch mode of the amplifier ad-libitum and for a relatively long time (to be at an exhibition), and my impression were that even if the triod mode was more colored and the mids were definitely more forward than in ultra linear mode, the amp did not lose the dynamics and the precision.
That was the main feature that impressed me most. 
Also the detail retrieval was very good too, and I cannot say that it was only because of the cans, as those cannot play something that doesn’t come out from the amp. 
in a further talk with Andy defined the HA-6A as a “modern” tube amp. 
A versatile amp that may be suitable for a wide range of musical styles, including some modern electronic music.
I think he was right  
How much my feeling was true and linked to the emotional side of my brain rather than the rational? I don’t know, and that’s one of the reasons I want to listen to it again in a more relaxed situation with the headphones that I normally use at home (Focal Clear, Aeon close back, HD650).


----------



## Faber65 (Mar 6, 2020)

Here


Relaxasaurus said:


> Auris Euterpe ($1700) and a Manley Absolute ($4500).



Here in China the Euterpe is sold for USD 3000 and the Manley for 5500. While at the current exchange rate the price of the HA-6A is USD 1990.


----------



## GU1DO

Relaxasaurus said:


> My initial impressions:
> 
> *HFM Arya:*
> Amp appears to be dead silent. Great build quality on the outside looks to be happening on the internals as well. That said with the planars I wasn't impressed to the level I was testing out other tube amps at Canjam. I liked what I was hearing but it wasn't like the feeling I experienced plugging the Aryas into an Auris Euterpe ($1700) and a Manley Absolute ($4500).
> ...


Please don't forget to do burn in for at least 50-70hrs before any critical listening , can't wait to see how the review will go on


----------



## MSA1133

This was a super pleasant surprise! The HA-6A easily ran the power hungy ABYSS 1266 TCs with no issues in both TR & UL modes! On High Impedance, the volume knob was at 11 O'Clock and the dynamics, bass response/impact and volume were extremely satisfying. This was fed from my PC -> Hugo 2 -> RCA cables -> Cayin HA-6A. I'm inexperienced with Tube Amps, however, this setup drew a big grin on my face. A quick 10 minutes session before bed turned into something else!


----------



## Andykong

Relaxasaurus said:


> Unboxing is up. My first video so be gentle :]
> 
> 
> 
> Trying to get my hands on some other headphones and/or equipment to see how it performs with different gear. If you're in the NYC area and want to either loan me or be in the review msg me.




A very enjoyable open-box for Cayin HA-6A, its very informative and yet you have captured the excitement very well, good job indeed.


----------



## Relaxasaurus (Mar 14, 2020)

Andykong said:


> A very enjoyable open-box for Cayin HA-6A, its very informative and yet you have captured the excitement very well, good job indeed.


Thanks Andy! I really enjoyed unboxing the amp, and listening to it even more 

I did have some questions for you regarding the HA-6A:

Is the volume pot the same aluminum shielded 24-step pot in the HA-300?


Aside from the audible hiss for sensitive headphones how did you guys get this tube amp so quiet? 


I'm trying to get a more lush, mid-forward sound out of the HA-6A. Are there any tubes you or the engineers recommend for this route?


Do you recommend we change out the 12au7 tubes *first *before either the EL34/KT88 tubes to alter the sound signature? I know you mentioned this for the HA-300 in its thread.


I saw Cayin posted some Coronavirus updates in the above mentioned thread, curious if the same halt of production applies to the HA-6A's April release date. We want everyone overseas to take as much time and safety as possible so we understand if there's a delay.
Thanks for the wonderful support and information so far. Cayin has been killing it with their headphone amp offerings the past couple of years.


----------



## Relaxasaurus

Just a quick update, was hoping to post my review today but truth be told I still wasn't satisfied from the sound coming out of my planars. I read around quite a bit and decided to pick up some Mullard 12au7 tubes (in addition to EL34 tubes of the same brand). They finally arrived today, and what an enormous change in sound signature compared to the stock Eletrco-Harmonix! I guess I'm officially a tube roller 

I'm grinning ear-to-ear and completely in love with this amp. Will get back on the camera asap


----------



## SonnyMarrow

Relaxasaurus said:


> Just a quick update, was hoping to post my review today but truth be told I still wasn't satisfied from the sound coming out of my planars. I read around quite a bit and decided to pick up some Mullard 12au7 tubes (in addition to EL34 tubes of the same brand). They finally arrived today, and what an enormous change in sound signature compared to the stock Eletrco-Harmonix! I guess I'm officially a tube roller
> 
> I'm grinning ear-to-ear and completely in love with this amp. Will get back on the camera asap



I look forward to the full review! Do you know what the actual output impedance is at the lowest setting? The Cayin page says 8-64 ohms, which might be too much for the 32 ohm headphones I just purchased.


----------



## Relaxasaurus

SonnyMarrow said:


> I look forward to the full review! Do you know what the actual output impedance is at the lowest setting? The Cayin page says 8-64 ohms, which might be too much for the 32 ohm headphones I just purchased.


I'm not sure myself! At the time of purchase there was no manual fully translated in English for Cayin to include. Is there another way to find this out?


----------



## GU1DO

Relaxasaurus said:


> Just a quick update, was hoping to post my review today but truth be told I still wasn't satisfied from the sound coming out of my planars. I read around quite a bit and decided to pick up some Mullard 12au7 tubes (in addition to EL34 tubes of the same brand). They finally arrived today, and what an enormous change in sound signature compared to the stock Eletrco-Harmonix! I guess I'm officially a tube roller
> 
> I'm grinning ear-to-ear and completely in love with this amp. Will get back on the camera asap


Cant wait for your impressions and review , i am looking for a tube amp and it is mainly between this amp and its big brother , i am leaning toward this one because it has more tuning options though i wish it can power my HE6se


----------



## SonnyMarrow

Relaxasaurus said:


> I'm not sure myself! At the time of purchase there was no manual fully translated in English for Cayin to include. Is there another way to find this out?



Yeah but you'd need a resistor and a mulitimeter, which is a hassle.


----------



## Andykong

Relaxasaurus said:


> Thanks Andy! I really enjoyed unboxing the amp, and listening to it even more
> 
> I did have some questions for you regarding the HA-6A:
> 
> Thanks for the wonderful support and information so far. Cayin has been killing it with their headphone amp offerings the past couple of years.



Check my response in blue:

Is the volume pot the same aluminum shielded 24-step pot in the HA-300?
Yes, HA-300 and HA-6A shared the same volume pot.


Aside from the audible hiss for sensitive headphones how did you guys get this tube amp so quiet? 
We learned a lot from the HA-300 which runs on  Direct Heated Triodes, DHT are more sensitive to micorphoic than EL34 and KT88.  Besides, we design and produce our own power transformers and output transformers, they are 100% fit to our design and requirements.


I'm trying to get a more lush, mid-forward sound out of the HA-6A. Are there any tubes you or the engineers recommend for this route?
Sorry, I am not that familiar with the sound signature of different 12AU7.


Do you recommend we change out the 12au7 tubes *first *before either the EL34/KT88 tubes to alter the sound signature? I know you mentioned this for the HA-300 in its thread.
If  you want to get a more lush, mid-forward sound, I suggest you switch the power tube to EL34 and then start to roll the 12AU7.  To my ears, the KT88 are relatively more neutral while the EL34 sounds more lush, so EL34 is a better starting point to you.


I saw Cayin posted some Coronavirus updates in the above mentioned thread, curious if the same halt of production applies to the HA-6A's April release date. We want everyone overseas to take as much time and safety as possible so we understand if there's a delay.
Up to this moment, we are still expecting a HA-6A production run by early April. We are getting better every day, and product that are less depends on  US and Japan component tends to be safer in our schedule.


----------



## Andykong

Relaxasaurus said:


> Just a quick update, was hoping to post my review today but truth be told I still wasn't satisfied from the sound coming out of my planars. I read around quite a bit and decided to pick up some Mullard 12au7 tubes (in addition to EL34 tubes of the same brand). They finally arrived today, and what an enormous change in sound signature compared to the stock Eletrco-Harmonix! I guess I'm officially a tube roller
> 
> I'm grinning ear-to-ear and completely in love with this amp. Will get back on the camera asap



I responded to your previous post before I read your update, glad you find a combination that feed your preference.

Now that you are tube roller converted, does that mean you'll try our more tube combination down the road?  That's interesting.


----------



## Andykong

SonnyMarrow said:


> I look forward to the full review! Do you know what the actual output impedance is at the lowest setting? The Cayin page says 8-64 ohms, which might be too much for the 32 ohm headphones I just purchased.



Trust me, 32ohm headphone is fine with the low impedance setting.  By the way, is that dynamic or a planar?


----------



## SonnyMarrow

Andykong said:


> Trust me, 32ohm headphone is fine with the low impedance setting.  By the way, is that dynamic or a planar?



It's a new dynamic headphone called the Aurorus Borealis. I've wanted a tube amp since going to CanJam this year and hearing what tubes do to my HD600. But then I learned about output impedance matching and wanted to be able to use the Borealis with any amp as well. I was looking into hybrid amps, but if the HA-6A will work, I'll likely get that


----------



## Relaxasaurus

Thanks for the responses @Andykong . I posted my full review here:



Let me know if I missed anything


----------



## Zachik

Relaxasaurus said:


> Thanks for the responses @Andykong . I posted my full review here:
> 
> 
> 
> Let me know if I missed anything



Great review!! Thanks.


----------



## Relaxasaurus

Zachik said:


> Great review!! Thanks.


Much appreciated! Please like & subscribe for the YT algorithm. Once I can start collecting revenue from these videos I can justify to my wife all these equipment purchases lol


----------



## Andykong

Relaxasaurus said:


> Thanks for the responses @Andykong . I posted my full review here:
> 
> 
> 
> Let me know if I missed anything




Thank you very much for sharing your experience and impression with us.  This is a wonderful review, informative and extremely helpful.

Base on your description of personal preference in the review, I'll suggest you consider the antique models from Sennheiser.  600 ohm version HD540 comes to my mind immediately, HD250 Linear 1 should also works fine with you, but they are even harder to locate.  The sound signature of these headphones fit your sound preference right on, they are not expensive, you just need to spend time to hunt them down, make sure they are still in good condition  and the earpad are still  useable. 

This is an example of HD540 at eBay, unfortunately the seller didn't specify whether this is an 300ohm or 600ohm vesion. 
https://www.ebay.com/itm/Sennheiser...tereo-headphones-earphones-3-5mm/113999865067


----------



## ls13coco (Mar 26, 2020)

Relaxasaurus said:


> Much appreciated! Please like & subscribe for the YT algorithm. Once I can start collecting revenue from these videos I can justify to my wife all these equipment purchases lol



Great review. I was being pushed away on the idea of this amp after impressions started trickling in, but that change of the 12au7 tubes suggests it would get exactly where I want. I wonder if they will start offering these, or other tube options upon purchase.

I am curious if you could elaborate more on your thoughts between the KT88 and EL34 running, though, as well as TR vs UL tube to tube.
Also, did you find the lower impedance setting to be sufficient for the Arya, or did you bump that up?


----------



## Relaxasaurus (Mar 26, 2020)

ls13coco said:


> I am curious if you could elaborate more on your thoughts between the KT88 and EL34 running, though, as well as TR vs UL tube to tube.
> Also, did you find the lower impedance setting to be sufficient for the Arya, or did you bump that up?


Thanks for the kind words and sure thing. As you can tell from the video I'm looking for more of a lush, sweet & mid-forward sound. EL34 tubes in triode mode accomplish this better than any other configuration.

*EL34 + TR* = smooth, lush, sweet mids and non-fatiguing sound. Details are definitely smoothed out to accomplish this but I personally prefer this config most of the time. It's just a joy to listen to.
*EL34 + UL *= same smooth sound, but the "lushness" factor decreases a couple of notches, replaced by more high frequency detail coupled with more precise layering. I hear nuances like instrument echoes in much more detail. Still an overall "polite sound" to my ears compared to solid state but I know my ears will get fatigued the longer I hear in this mode.

*KT88 + TR *= full-bodied, balanced sound that doesn't necessarily focus on a mid-forward presentation. Still non-fatiguing in triode mode, but a bit flavorless to my ears compared to EL34.
*KT88 + UL *= full-bodied sound still there plus the added impact from tracks that have higher energy such as pop or even jazz. Very clean sound overall but not my cup of tea, unless there is a KT88 tube that can provide the balance of the stock Genalec Gold Lions + the lushness of my Mullard reissued EL34's.

YMMV with everything here. Listeners may prefer to stick with the high quality stock Gold Lions and call it a day.


----------



## ls13coco

Thank you very much for the detailed information, this is exactly what I have been most curious about. I assume these impressions are all after the 12au7 roll, however your description of the EL34 in triode mode is exactly what I'm looking to achieve.
It almost seems that running the amp in UL with the the KT88 could take the place of many SS amps, with I'd imagine a slight warm tilt (comparable to warmer SS amps).

Thanks again for your impressions!
(only now I can hope for a ha-6a vs ha-300 comparison!)


----------



## Relaxasaurus

ls13coco said:


> Thank you very much for the detailed information, this is exactly what I have been most curious about. I assume these impressions are all after the 12au7 roll, however your description of the EL34 in triode mode is exactly what I'm looking to achieve.
> It almost seems that running the amp in UL with the the KT88 could take the place of many SS amps, with I'd imagine a slight warm tilt (comparable to warmer SS amps).
> 
> Thanks again for your impressions!
> (only now I can hope for a ha-6a vs ha-300 comparison!)


Yes, I updated all my review notes after I rolled with the Sylvanias.

I'd love to get my hands on an HA-300 (and subsequently the HA-1A mk2). From everything I've read the 300 will give an even more lush sound, but it has the tendency to suffer from more microphonics & interference due to the nature of the 300B tube and DHT. The owners though, absolutely love this amp and you see very few get resold.

When things slowly get back to normal I'll see if I can get my hands on a review unit


----------



## LTd head

ls13coco said:


> only now I can hope for a ha-6a vs ha-300 comparison!


Count me too! Though the price difference are not comparable  But the flexibility of this amp is on top!
How about the synergy with HD800 - hard to drive, but tube rolling should do the thing or I should look else?


----------



## vcoheda

Relaxasaurus said:


> Thanks for the responses @Andykong . I posted my full review here:
> 
> 
> 
> Let me know if I missed anything




very informative. thanks for posting.


----------



## Relaxasaurus

vcoheda said:


> very informative. thanks for posting.


Thank you, was worried it was too long but I actually cut a good bit out lol.



LTd head said:


> Count me too! Though the price difference are not comparable  But the flexibility of this amp is on top!
> How about the synergy with HD800 - hard to drive, but tube rolling should do the thing or I should look else?


I hope this to be my next purchase. Was contemplating selling the Arya's for an HD800S but I love planar sound way too much.  The Sennheiser and an Empy are the only headphones I have my sights on right now.

In terms of how it would sound on the Cayin, when I bought the Arya I did a critical listening session on it vs the HD800S and the latter did beat out the Arya in classical by a good margin. Violins sounded more realistic and orchestral music did sound more natural to my ears. The Arya won on soundstage, bass response, and pure speed so it was more of a well-rounded HP for all sorts of genres. Considering how the other dynamics fared in the review I bet the 800/S will really shine on the HA-6A. You have close to the attack of the Arya on speed while have more of a warmer, mid-focused presentation.


----------



## Marutks

MidFi Guy said there is background noise (hiss).   Are you not worried about it at all?   I wouldn't want to spend so much money on amplifier that has audible hiss.


----------



## Relaxasaurus

Marutks said:


> MidFi Guy said there is background noise (hiss).   Are you not worried about it at all?   I wouldn't want to spend so much money on amplifier that has audible hiss.


Just did some more testing with different tubes, changing TR/UL modes, changing to a less used power outlet, using a non-grounded power cable, etc... The hiss is there but it's only really noticeable on the HD650 when the impedance selector is on High, and it virtually disappears when you're listening to music.

Here's a list of the dynamics I'm able to test, all in high impedance mode (since the hiss is only really audible here), in order of loudest hiss to lowest (ohms / sensitivity):

Senn HD6XX (300Ω  / 103db)
Meze 99 Noir Classics (32Ω  / 103db)
Sony Z7 (70Ω  / 102db)
ZMF Aeolus (300Ω  / 99db)
The HD6XX was the loudest by a bigger margin compared to the others, in fact it's the only one whose hiss is fairly audible in medium impedance as well. I have a sound meter and tried to measure the difference but it wasn't picking up any change (I probably need those miniDSP EARS for isolation).


----------



## Baten

Marutks said:


> MidFi Guy said there is background noise (hiss).   Are you not worried about it at all?   I wouldn't want to spend so much money on amplifier that has audible hiss.


Most tube amps have a noise floor. It's pretty much expected if you go tube over solid state :/


----------



## Marutks

Baten said:


> Most tube amps have a noise floor. It's pretty much expected if you go tube over solid state :/



My ECP T4 tube amp doesn't have noise floor.    I had C3X solid state amp which has very high noise floor.
I think it depends on output power.   Most high powered amplifiers don't have audible noise only when used with planar magnetic headphones.


----------



## Relaxasaurus

Don't know if you all have been following the comment thread on Youtube but we narrowed down the hiss to the 4-pin balanced XLR output. If I use the HD6XX with the 1/4" single-ended jack I get no hiss.

I can definitely live with this, especially since *a)* the decreased power output provides better steps with the volume pot levels and *b)* the amplification happens in single-ended mode anyway. That said @Andykong maybe the Cayin engineers can look at why the 4-pin balanced output creates hiss with high impedance headphones? Is it just my unit?


----------



## Marutks

Relaxasaurus said:


> we narrowed down the hiss to the 4-pin balanced XLR output. If I use the HD6XX with the 1/4" single-ended jack I get no hiss.



The same happened with C3X and my Verite headphones.


----------



## Andykong

Relaxasaurus said:


> Don't know if you all have been following the comment thread on Youtube but we narrowed down the hiss to the 4-pin balanced XLR output. If I use the HD6XX with the 1/4" single-ended jack I get no hiss.
> 
> I can definitely live with this, especially since *a)* the decreased power output provides better steps with the volume pot levels and *b)* the amplification happens in single-ended mode anyway. That said @Andykong maybe the Cayin engineers can look at why the 4-pin balanced output creates hiss with high impedance headphones? Is it just my unit?



That is because the Rated Power Output and Residual Noise Level of High Impedance setting is higher then both Mid and Low impedance significantly, and the rated output of XLR4 is slightly higher then 6.35mm.   In other word, the HA-6A is operated at its PEAK at high impedance XLR4 output.  

The Residual Noise level is not a published specification in normal practise, you won't find this in the specification of most, if all not all, amplifier, be it speaker amplifiers or headphone amplifiers.  If you understand the factors behind residual noise, then you'll understand the correlation among residual noise, impedance and output level. 

HA-6A offers a very wide range of output power to our users, this is, supposingly a pros to offer more flexibility to our users so that they can match with different headphones with confident.  However, if you insist to use the highest output power setting to drive the sensitive headphones, then you are turning a pros into a cons.  To put this into context, with the same set of power tube (i.e., without changing from KT88 to EL34) the lowest output power setting is Triode mode + Low Impedance + Single-ended output (6.35mm), and the highest output power setting is Ultralinear mode + High Impedance + Balanced (XLR4 or 4.4mm).  Roughly speaking, the later (UL+H+BAL) is around 7 times higher than the first (TR+L+SE) setting.  

If you are numerical mind and want to find out how these numbers worked out, I can elaborate further below, but I guess some users will be bored by these numbers.

In our product specification, we only published the output rating in watt, this is subject to loading (impedance) so not a straight forward numbers if you want to compare the output rating across different loading.  However, you can work out the voltage level (designated as Vrms in specification) according to the following formula and that will allow you to compare the figure in with linear numbers:
V = SQRT (W*R), or W= V^2 / R 

Let's elaborate the KT88 output rating for discussion.   I don't know the actual impedance loading of this setting, but since we are comparing the effect of different setting instead of measuring the output rating under different condition, let's* ASSUME* the loading of L is 64ohm, M is 250ohm, and H is 600ohm for the time being. 

The first set of data compare four different setting of LOW impedance output, and the output level are 7.16V, 8.76V, 8.76V and 11.03V respectively.  In other word, at Low impedance, change from SE to BAL will increase output by 22% , From TR to UL will also increase output by 22%, and change from TR+SE to UL+BAL will increase output by 54%, not very substantial but still noticeable. 

However if we change to Mid and High impedance loading, the output level at UL+BAL will bump to 27.39V and 51.96V respectively.  When compare to the baseline output at 7.16V (TR+L+SE), we achieved "roughly" 3.8x and 7.3x, quite an astonishing multiplier if you don't compare them in linear numbers.






One last comment: the effect of different setting might worry in different impedance loading.  For example, if we change our focus to High impedance, the four different setting will deliver output level at 38.73V, 43.82V, 46.48V, and 51.96V respectively.  When compare to the High Impedance baseline, the multiplier is now lowered to 1.13, 1.2, and 1.34 respectively, quite a bit lower than the multiplier of Low impedance loading.

Please be reminded that these are "assumptions" to facilitate discussion, I don't have the actual impedance loading of L, M, H output off-handed (and this is 10:30pm, now the right time to call up the Engineer to clarify the setting).  However, I hope we have clarified the situation and we don't need to worry about hissing problem with high sensitive headphones because of  the low level background noise at High Impedance XLR4 output.


----------



## Relaxasaurus

Working from home has its benefits for our hobby, but not when your child needs to use the computer to listen to a video lesson


----------



## Celty

Relaxasaurus said:


> Working from home has its benefits for our hobby, but not when your child needs to use the computer to listen to a video lesson


What kind of father are you? Clearly, this poor girl needs her own set-up. At least she does get Pizza to give her solace from her tech deprivation!


----------



## Relaxasaurus

Celty said:


> What kind of father are you? Clearly, this poor girl needs her own set-up. At least she does get Pizza to give her solace from her tech deprivation!


I've failed my family!


----------



## OctavianH

Happy Chicken Day? NO! Headphone day!


----------



## Fatdoi

Relaxasaurus said:


> Working from home has its benefits for our hobby, but not when your child needs to use the computer to listen to a video lesson


I can't wait to share my hobby with my daughter when her ears trained enough to appreciate good sound qualities...


----------



## Relaxasaurus

Haha!

Was going to post this over the weekend but I noticed the Pre-order button is now an "Add to cart" button. I guess they're in stock now:

https://shop.musicteck.com/products/cayin-ha-6a-el34-kt88-vacuum-tubes-headphone-amplifier


----------



## GU1DO

I think this video should be shared here . Nice work Relaxasaurus , i watched your first review bth i had mixed feelings , so i thought i would give this amp more time for more feedback and i guess this video give a very good impression how the Cayin HA-6A sound with variety of headphones , thanks for the great honest review and please keep up the great work .


----------



## GU1DO

Forgot to ask , at which impedance you liked the HD800 at ? 
any difference with different settings ?


----------



## OctavianH

Great video, I really enjoyed it and if you add the T1.2 to the comparison, you are the Headphone King of the Youtube


----------



## Relaxasaurus

Thanks for the nice words! I'm doing a WA22 vs HA-6A video soon. I'll test out the impedance differences then.

Octavian I wish I had some nice Beyer's. How do you like them with tube amps?


----------



## OctavianH

Relaxasaurus said:


> Octavian I wish I had some nice Beyer's. How do you like them with tube amps?



T1 are very good with tube amps, I would say they shine on tubes, I tried them with A2 and Elise and kept Elise even if A2 is not quite a bad amp.


----------



## ls13coco

Relaxasaurus said:


> Thanks for the nice words! I'm doing a WA22 vs HA-6A video soon. I'll test out the impedance differences then.
> 
> Octavian I wish I had some nice Beyer's. How do you like them with tube amps?



You are doing God's work lol.
Look very forward to this.. only wish you had an Empy to use in these comparisons too.


----------



## Dietmar Görtz

Hi all!

I am very interested in the HA-6A.
Is there noise with low impedance headphones? Or is he dead silence?

Best regards,

Dietmar


----------



## Relaxasaurus

Dietmar Görtz said:


> Hi all!
> 
> I am very interested in the HA-6A.
> Is there noise with low impedance headphones? Or is he dead silence?
> ...


I get zero noise from low impedance planars. With dynamics there are hiss issues at 4-pin XLR out + high impedance selected. Andy Kong explains why two pages back or so but it's basically because of the massive amount of power being outputted with that combination.

I'll try a low impedance dynamic + single ended out + low impedance selected later and will let you know how it sounds.


----------



## Relaxasaurus (May 13, 2020)

Just confirming there is still hiss but only on dynamics. If you have dynamics you'll only want to use the single ended output for them. Tested 32, 70, and 300Ω dynamics and got major hiss on the balanced 4-pin XLR port. This is both in the stock tube configuration and my NOS tube config.

If you have planars then both the single and balanced outputs will exhibit zero noise.


----------



## Dietmar Görtz

I have a Meze Empyrean, Hifiman HE1000SE and Abyss Phi TC. 
All with XLR balanced connection. 
Does anyone have any experience? Hum?

Best,

Dietmar


----------



## GU1DO (May 13, 2020)

Dietmar Görtz said:


> I have a Meze Empyrean, Hifiman HE1000SE and Abyss Phi TC.
> All with XLR balanced connection.
> Does anyone have any experience? Hum?
> 
> ...


I puled the trigger and expecting mine within few weeks ,
my main use would be with dynamics (HD800/6x0/ADX5000) but lets see how it perform with planers  (HEKse/HE6se/OG Abyss).


----------



## GU1DO

Relaxasaurus said:


> Just confirming there is still hiss but only on dynamics. If you have dynamics you'll only want to use the single ended output for them. Tested 32, 70, and 300Ω dynamics and got major hiss on the balanced 4-pin XLR port. This is both in the stock tube configuration and my NOS tube config.
> 
> If you have planars then both the single and balanced outputs will exhibit zero noise.


Is your power grounded ?


----------



## Relaxasaurus

GU1DO said:


> Is your power grounded ?


Yes, tried two different power sockets in different rooms too just to confirm.

Congrats on your HA-6A purchase!! You'll have to let me know how yours handles dynamic cans. Want to know if I need to reach out to Cayin :x


----------



## GU1DO

Relaxasaurus said:


> Yes, tried two different power sockets in different rooms too just to confirm.
> 
> Congrats on your HA-6A purchase!! You'll have to let me know how yours handles dynamic cans. Want to know if I need to reach out to Cayin :x


Thanks , actually your last video was the motive to try this amp more and more hehe , so i should thank you , 
i was tempted to try its bigger brother the HA300 but the lack of push/pull thing was a factor because i like more options for tweeks , beside that i felt it is overpowered for my needs so i went for the HA6A, hopefully the hiss would not be an issue but will see how it goes.


----------



## Relaxasaurus

GU1DO said:


> Thanks , actually your last video was the motive to try this amp more and more hehe , so i should thank you ,
> i was tempted to try its bigger brother the HA300 but the lack of push/pull thing was a factor because i like more options for tweeks , beside that i felt it is overpowered for my needs so i went for the HA6A, hopefully the hiss would not be an issue but will see how it goes.


Hah, that's great! Just noticed your DAC too, this is what I'm listening to right now


----------



## GU1DO

Relaxasaurus said:


> Hah, that's great! Just noticed your DAC too, this is what I'm listening to right now


Niceeee , cant wait for the review LOL 😁


----------



## Sound Eq

can i ask if that hiss on balanced is very obvious during between songs or low passages  pf music

are all tubes amps that are balanced suffer from noise, like i am looking at woo audio w22. which is bout the same price

did anyone compare cayin ha-6e to woo audio w22


----------



## Relaxasaurus

Sound Eq said:


> can i ask if that hiss on balanced is very obvious during between songs or low passages  pf music
> 
> are all tubes amps that are balanced suffer from noise, like i am looking at woo audio w22. which is bout the same price
> 
> did anyone compare cayin ha-6e to woo audio w22







So far, not getting any hiss on the WA22 with dynamics. :x

The bigger question is does this happen to other people's units? @GU1DO is getting his delivered, would love to hear his verdict.


----------



## Relaxasaurus

Oh, and the hiss is noticeable between songs on balanced only. I don't really hear it on single ended unless I look for it or toggle the headphone output switch.


----------



## Sound Eq

Relaxasaurus said:


> So far, not getting any hiss on the WA22 with dynamics. :x
> 
> The bigger question is does this happen to other people's units? @GU1DO is getting his delivered, would love to hear his verdict.


i watched your video and wonder which will be having the upper hand in sound, I like you want a great tube amp to complement my chord tt2, not a tube amp that sounds like solid state

did u audition the auris euterpe, and its amazing for 1600 usd and I now am ready to take the bigger jump after haring the auris eterpe, also the absolute manely and auris nirvana all got me interested as well


----------



## Relaxasaurus

Sound Eq said:


> i watched your video and wonder which will be having the upper hand in sound, I like you want a great tube amp to complement my chord tt2, not a tube amp that sounds like solid state
> 
> did u audition the auris euterpe, and its amazing for 1600 usd and I now am ready to take the bigger jump after haring the auris eterpe, also the absolute manely and auris nirvana all got me interested as well


I heard the Euterpe at Canjam and loved it! They wouldn't budge on price at the event so I got the Cayin instead 

Will most likely post the video next week!


----------



## Andykong

Relaxasaurus said:


> Oh, and the hiss is noticeable between songs on balanced only. I don't really hear it on single ended unless I look for it or toggle the headphone output switch.



What is the headphone cable you are using? I would like to know the structure of the headphone cable.  4 wire or 8 wires with XLR4 terminated?

If you only hear the noise with balanced headphones but not single-ended, then there is a good chance that the noise is interfere with the headphone cable work.  With single-ended, there is a ground signal in the cable, so you won't hear any interfere.  For XLR4 balanced headphone cable, it doesn't have ground pin, so if the conductors are not shielded properly, the headphone cable will become ab antenna, picking up noise when connected to the tube headphone amplifier.


----------



## Zachik

Andykong said:


> What is the headphone cable you are using? I would like to know the structure of the headphone cable.  4 wire or 8 wires with XLR4 terminated?
> 
> If you only hear the noise with balanced headphones but not single-ended, then there is a good chance that the noise is interfere with the headphone cable work.  With single-ended, there is a ground signal in the cable, so you won't hear any interfere.  For XLR4 balanced headphone cable, it doesn't have ground pin, so if the conductors are not shielded properly, the headphone cable will become ab antenna, picking up noise when connected to the tube headphone amplifier.


Andy - wouldn't higher power to balanced vs. SE explain the hiss / noise?


----------



## GU1DO

Relaxasaurus said:


> So far, not getting any hiss on the WA22 with dynamics. :x
> 
> The bigger question is does this happen to other people's units? @GU1DO is getting his delivered, would love to hear his verdict.


I am waiting for the tracking # they didn't ship it yet , though i am seeing it popping in really good prices in the chines sites so i guess we will see more feedback next few weeks, tbh i bought this amp primarily for high impedance headphones , so fingers crossed


----------



## GU1DO

MSA1133 said:


> This was a super pleasant surprise! The HA-6A easily ran the power hungy ABYSS 1266 TCs with no issues in both TR & UL modes! On High Impedance, the volume knob was at 11 O'Clock and the dynamics, bass response/impact and volume were extremely satisfying. This was fed from my PC -> Hugo 2 -> RCA cables -> Cayin HA-6A. I'm inexperienced with Tube Amps, however, this setup drew a big grin on my face. A quick 10 minutes session before bed turned into something else!


hi , i was re-reading the whole thread and i just noticed your post ,, do you experience any hiss with any headphone with the HA6A ?


----------



## IPMano

I've HA-1A MKII since 2 week for replace my little dot MK2 tunning (caps, valve, resistors), wowwwww very nice sound with 12AU7 Pvsane, and this day i buy HA-6A i hope receive it this week.
Later I will buy an HD800S, I already have a T90


----------



## Faber65

Dietmar Görtz said:


> I have a Meze Empyrean, Hifiman HE1000SE and Abyss Phi TC.
> All with XLR balanced connection.
> Does anyone have any experience? Hum?
> 
> ...


Well, At the last CanJam in Shanghai, the Meze Empyrean were matched with a pre-built unit of the HA-6A.
This should say a lot, if not all.....


----------



## Dietmar Görtz

Can you describe it, please!


----------



## GU1DO

> If you are dreaming to buy a tube headphone amplifier, the Cayin HA-6A could be a hot recommendation for you. We have this beautiful and massive designed headphone-amp under review and we are totally convinced about the power, the dynamics, soundstage and resolution. Curious? Do not miss our review beginning of June at www.lite-Magazin.de


https://www.instagram.com/p/CAXyA-zoWqD/?igshid=1b6ldze2olcm6n


----------



## Relaxasaurus

GU1DO said:


> https://www.instagram.com/p/CAXyA-zoWqD/?igshid=1b6ldze2olcm6n


Nice find! If they say anything about the hiss on dynamics I'll die. Actually if they *don't *say anything about the hiss I'll die. Either way, I'm


----------



## GU1DO

Relaxasaurus said:


> Nice find! If they say anything about the hiss on dynamics I'll die. Actually if they *don't *say anything about the hiss I'll die. Either way, I'm


No please dont die , i like your new YouTube channel  but seriously its not a big deal other than the hassle of shipping it back, btw hiss appear in all tubes you tried ?
Also i just got the tracking # so i started looking for tubes and was wondering how the mullard  sound compared to the stock ?


----------



## Relaxasaurus

GU1DO said:


> No please dont die , i like your new YouTube channel  but seriously its not a big deal other than the hassle of shipping it back, btw hiss appear in all tubes you tried ?
> Also i just got the tracking # so i started looking for tubes and was wondering how the mullard  sound compared to the stock ?


Haha thanks. Hiss on every single tube I tried. The WA22 shootout my be a bit delayed as I'm talking with Andy K about the issue. Hopefully we can get it rectified.

From memory on the driver tubee, the new production Mullards I was using make a slight difference but I much preferred the sound from the NOS Sylvanias.

Curious how people will tube roll here. As much as I love tube sound I don't have the patience for trying out 2 dozen tube combinations 🥴


----------



## Zachik

Relaxasaurus said:


> Curious how people will tube roll here. As much as I love tube sound I don't have the patience for trying out 2 dozen tube combinations 🥴


Well... you should never get a Glenn OTL (GOTL) amp, then!
The GOTL supports WAY WAY more tube combinations


----------



## Relaxasaurus

Zachik said:


> Well... you should never get a Glenn OTL (GOTL) amp, then!
> The GOTL supports WAY WAY more tube combinations


Oh I want one, bad... to review!


----------



## GU1DO

Relaxasaurus said:


> Haha thanks. Hiss on every single tube I tried. The WA22 shootout my be a bit delayed as I'm talking with Andy K about the issue. Hopefully we can get it rectified.
> 
> From memory on the driver tubee, the new production Mullards I was using make a slight difference but I much preferred the sound from the NOS Sylvanias.
> 
> Curious how people will tube roll here. As much as I love tube sound I don't have the patience for trying out 2 dozen tube combinations 🥴


I am sure you are going to like the warmth of the Woo Audio amps , i tried them before , nice amps but too much lacking in details for my taste though my listening was before long time ago on the WA6\WA5 not the WA22 , so a fresh more matching comparison would be nice , 

About tubes same here I don't have the patience to mix and match so i just ordered Tung-Sol EL34 as alternative to the stock , for the 12AU7 i ordered Tung-Sol , Mullard , Gold Lion all reissue and one pair NOS Brimar CV4003 which i liked so much with my Crack amp , i couldn't find Sylvania for a good price so i will keep searching , later i may explore more tubes but after giving it a listen with these regular tubes.


----------



## GU1DO

Relaxasaurus said:


> Oh I want one, bad... to review!


Good luck contacting glenn , he is so busy person


----------



## comzee

Andykong said:


> To the best of our knowledge, this is the first ever tube headphone amplifier offers triode and ultra-linear mode selection, if you know of any previous product equipped with similar features, please let us know and we'll be most delighted to explore the pros and cons of different implementations.



Not sure if you were also including DIY, but Elekit TU-8800 does Triode/UL modes, with 3 B+ settings to go anywhere from 6v6/6f6 to kt88/kt150. Very similar features to the Cayin. Although the TU-8800 doesn't have output impedance switch, that is a killer feature.

Overall the Cayin HA-6A looks like an amazing amp. Packed with features, really looks like an end-game totl headphone amp.
If I didn't already own a bespoke pentode headamp I'd jump on it.

If I was to change only one thing on the HA-6A, it would have been nice if it used standard 2/3amp full wave rectifier (5r4/5u4 families) instead of two half wave 22DE4 tubes.


----------



## GU1DO

I just got the amp and the build quality is second to none , very amazing , 

i didnt play it for long time nether did any burning but i can confirm the hiss on the balanced output even in low gain , i am using power conditioner  and high quality power cable and this hiss does not occur in any other amp , so i guess i will give it few days and try to swap tubes which i already bought , hopefully this issue will get sorted.



















and here is a comparison to AudioGD Master 9 though the HA6A feel much heavier


----------



## Relaxasaurus

What a beautiful monster. Thanks for the great pics.

Wondering how HA-300 owners are getting no hiss while the HA-6A gets it on balanced out. I'm guessing it's due to the TR/UL switching circuitry.

Do you get the hiss on planars?


----------



## GU1DO

Relaxasaurus said:


> What a beautiful monster. Thanks for the great pics.
> 
> Wondering how HA-300 owners are getting no hiss while the HA-6A gets it on balanced out. I'm guessing it's due to the TR/UL switching circuitry.
> 
> Do you get the hiss on planars?


On the HE6SE no hiss at all , and this amp can power it easily ,,
The HEKse there is little hiss though it is very sensitive headphone so i would say planers get less hiss in general , later i will try the 1266


----------



## Pictograms

Has anyone compared against the Ha-1a mkii? 
I am thinking about selling it to upgrade, this seems like a direct upgrade


----------



## Fatdoi

Pictograms said:


> Has anyone compared against the Ha-1a mkii?
> I am thinking about selling it to upgrade, this seems like a direct upgrade


I think HA6A is on different level to HA1A.... i will consider it's top end HP amp for those who don't prefer 300B..... once the hissing issue is sorted.


----------



## IPMano

on which headphone output does the hiss sound and is it loud ?


----------



## IPMano

Pictograms said:


> Has anyone compared against the Ha-1a mkii?
> I am thinking about selling it to upgrade, this seems like a direct upgrade



I do it, i receive 8 june, but now i'm afraid because there is a hiss output, maybe i delete my request.


----------



## Pictograms

IPMano said:


> I do it, i receive 8 june, but now i'm afraid because there is a hiss output, maybe i delete my request.


Reading through the thread has left me wondering how loud the hiss is, it seems like it’s only with the balanced output. 
Considering the balanced lowest power output 1000mw  and can reach 4500mw (depending on tubes and setting) It doesn’t seem that unexpected to me.
On my 1A-HA mk2 I never even go to half volume... maybe I should consider something with less power


----------



## IPMano

Pictograms said:


> Reading through the thread has left me wondering how loud the hiss is, it seems like it’s only with the balanced output.
> Considering the balanced lowest power output 1000mw  and can reach 4500mw (depending on tubes and setting) It doesn’t seem that unexpected to me.
> On my 1A-HA mk2 I never even go to half volume... maybe I should consider something with less power


You are from Canada, where ? maybe you speak french ?
I look Felik Audio Euphoria, but i want HA-6A, i like this look and i m very happy for my HA-1A MK II.


----------



## Pictograms

IPMano said:


> You are from Canada, where ? maybe you speak french ?
> I look Felik Audio Euphoria, but i want HA-6A, i like this look and i m very happy for my HA-1A MK II.



Yea, I love my HA1A mk2 had it for 2 years, that’s why I was I interested in the HA-6A. Are you able to return the HA-6A if it has to much noise?

I’m in Halifax and we don’t have many tube amps to demo. I think the closest Cayin dealer is in Quebec 

I was in Quebec last summer I couldn’t believe how much French I had forgotten, I used to be pretty okay now I can barely say bonjour, but I can read French okay.


----------



## IPMano (May 25, 2020)

Yes i have 2 week for return HA-6A.


----------



## GU1DO

IPMano said:


> I do it, i receive 8 june, but now i'm afraid because there is a hiss output, maybe i delete my request.


i highly suggest you wait and cancel your order


----------



## GU1DO

Pictograms said:


> Reading through the thread has left me wondering how loud the hiss is, it seems like it’s only with the balanced output.
> Considering the balanced lowest power output 1000mw  and can reach 4500mw (depending on tubes and setting) It doesn’t seem that unexpected to me.
> On my 1A-HA mk2 I never even go to half volume... maybe I should consider something with less power


its not loud but it is there , to me at this state is unusable , if not fixed i will return it back , i dont think it is a power issue , it is voltage issue , mainly dynamics with all impedance's has the hiss .


----------



## Fatdoi

GU1DO said:


> its not loud but it is there , to me at this state is unusable , if not fixed i will return it back , i dont think it is a power issue , it is voltage issue , mainly dynamics with all impedance's has the hiss .


seems my hope to own a OT tube amp is not happening again....


----------



## Slim1970

All this talk about hiss is concerning with this amp. I wonder if this is why it’s no longer available on Musicteck’s websight? I hope it’s being addressed by Cayin. The balanced output should be more quiet than the SE output in normal situations.


----------



## IPMano

What does Andykong think of this ?


----------



## IPMano

if i understand, it is only on the XLR output that there is the hiss? on the 6.3 jack output there is not this hiss?


----------



## Relaxasaurus

Long story short the American distributor has been discussing this with Cayin. Their engineers were able to reproduce the issue and they apparently have a fix but it requires a resistor change, so yes I would hold off on all orders at the time until update their production and have it back on the site.

They are sending me the resistors to try out but it's still in transit. That's about all I know at this point.

Hiss comes from all outputs when using dynamic headphones but is the worst on balanced XLR.


----------



## Andykong (May 25, 2020)

IPMano said:


> if i understand, it is only on the XLR output that there is the hiss? on the 6.3 jack output there is not this hiss?



To be exact, this problem. hiss on XLR4 outputs when using dynamic headphones,  only appear on @Relaxasaurus unit,  this is the first instance reported and we are studying it closely.  We haven't encountered any other case that exhibit similar problem.  We are working with Andrew from Musicteck to resolve this problem, unfortunately Andrew sold his demo unit recently, otherwise they can send a demo unit to Relaxasaurus for crosschecking and as temporary replacement.


----------



## GU1DO

Slim1970 said:


> All this talk about hiss is concerning with this amp. I wonder if this is why it’s no longer available on Musicteck’s websight? I hope it’s being addressed by Cayin. The balanced output should be more quiet than the SE output in normal situations.


Yeah they pulled it out few days ago , i ordered mine before that, and it is from Cayin china directly, hiss is very clear , problem is that i dont have other tubes , i am expecting new ones within next 2-3 weeks, hopefully Cayin will wait for me to try the new tubes otherwise its going back, crazy thing i was looking for an amp that can power planers and then changed my mind to dynamics, so i thought the HA6A with lower power rating than the HA300 , would be more suitable , this amp can power anything easily, it has crazy amount of power, i cant imagine how is the HA300.


----------



## GU1DO

IPMano said:


> if i understand, it is only on the XLR output that there is the hiss? on the 6.3 jack output there is not this hiss?


its in both output but it is very high in the balanced output ..


----------



## Zachik

GU1DO said:


> i thought the HA6A with lower power rating than the HA300 , would be more suitable , this amp can power anything easily, it has crazy amount of power, i cant imagine how is the HA300.


Based on a sample of 1 (my buddy's HA300) - no hiss at all. Been a while since we met (thanks COVID-19...) but I really was impressed by the HA300.


----------



## Fatdoi

GU1DO said:


> Yeah they pulled it out few days ago , i ordered mine before that, and it is from Cayin china directly, hiss is very clear , problem is that i dont have other tubes , i am expecting new ones within next 2-3 weeks, hopefully Cayin will wait for me to try the new tubes otherwise its going back, crazy thing i was looking for an amp that can power planers and then changed my mind to dynamics, so i thought the HA6A with lower power rating than the HA300 , would be more suitable , this amp can power anything easily, it has crazy amount of power, i cant imagine how is the HA300.


on earlier HA300 forum, some also had hissing issue.... think they've fixed it by now.


----------



## Andykong

GU1DO said:


> Yeah they pulled it out few days ago , i ordered mine before that, and it is from Cayin china directly, hiss is very clear , problem is that i dont have other tubes , i am expecting new ones within next 2-3 weeks, hopefully Cayin will wait for me to try the new tubes otherwise its going back, crazy thing i was looking for an amp that can power planers and then changed my mind to dynamics, so i thought the HA6A with lower power rating than the HA300 , would be more suitable , this amp can power anything easily, it has crazy amount of power, i cant imagine how is the HA300.



Let me help you to trace your case, I need the serial number of your HA-6A, will send you an PM to start the follow up process.


----------



## GU1DO

Andykong said:


> Let me help you to trace your case, I need the serial number of your HA-6A, will send you an PM to start the follow up process.


Thank you very much for the care and support.


----------



## GU1DO

Andykong said:


> Let me help you to trace your case, I need the serial number of your HA-6A, will send you an PM to start the follow up process.


i just tried the 4.4 output ,, it also has the hiss as the XLR output ,, this may help ?


----------



## Andykong

Zachik said:


> Andy - wouldn't higher power to balanced vs. SE explain the hiss / noise?





Pictograms said:


> Reading through the thread has left me wondering how loud the hiss is, it seems like it’s only with the balanced output.
> Considering the balanced lowest power output 1000mw  and can reach 4500mw (depending on tubes and setting) It doesn’t seem that unexpected to me.
> On my 1A-HA mk2 I never even go to half volume... maybe I should consider something with less power



If this is power related background noise, then the determining factor should be impedance and sensitivity of the headphones: you won't hear background noise with high impedance or low sensitivity headphones.  For instance, the headphone amplifier should be silent with 300Ohm HD6xx and HD800S. This doesn't seems to be the case here, so I don't think this is background noise related to high output power.


----------



## Andykong

Fatdoi said:


> on earlier HA300 forum, some also had hissing issue.... think they've fixed it by now.



Actually we have same comment at the earlier date of HA-1AMk2 as well.  In other word, all our previous  tube headphone amplifier are facing the same problem when released.  
So how do we solve the problems?  

It turns out that most of the noise problems are caused by:

interference 
power noise and ground loop;
tubes or installation of tubes
defective parts
So when there were several HA-300 or HA-1AMK2 users reported various noise problems, and then rectified their problems after get rid of the interference in their system, we don't see any complaints any more, because when someone raise the question again, other uses will shared their experience and encourage them to debug their system (check *HERE* and *HERE *for examples). 

I'll try to explain (1) to (3) in detail later, but trust me, you'll be amazed by the variety of interference.  When we discuss about  interference, we probably have "dirty" devices such as RF mouse, WiFi Router, mobile phones in mind, but what if I told you that your *USB cable*, light dimmer and computer *keyboard *are the source of interference?


----------



## IPMano

Hi all,

I have an HA-1A MKII, at the beginning with a DAC Nuprime DSD wired in USB on my PC and from DAC in RCA to the HA-1A MKII, I had a noise, it was the power supply of the PC which feeds the DAC in USB, I isolated the 5V power supply from the USB cable and powered the DAC by an external source, ouffff more noise.
Second problem, when I turn on the amplifier there is a background noise like a purring it is quite loud and after 15 - 20 seconds it becomes weaker but it is still there, I have not yet found the reason for this background noise, wouldn't it be heating AC tubes?

I really want to buy the HA-6A but I'm afraid of this hiss.

Sorry for my English, I am from Belgium and I use google translate.


----------



## Pictograms

IPMano said:


> Hi all,
> 
> I have an HA-1A MKII, at the beginning with a DAC Nuprime DSD wired in USB on my PC and from DAC in RCA to the HA-1A MKII, I had a noise, it was the power supply of the PC which feeds the DAC in USB, I isolated the 5V power supply from the USB cable and powered the DAC by an external source, ouffff more noise.
> Second problem, when I turn on the amplifier there is a background noise like a purring it is quite loud and after 15 - 20 seconds it becomes weaker but it is still there, I have not yet found the reason for this background noise, wouldn't it be heating AC tubes?
> ...


Do you have a wifi router close by?


----------



## Pictograms (May 26, 2020)

Not directly related to the Ha-6a, but related to tube amps. Some tubes pick up more radio frequency interference  other  and it can sound like scratching, purring or intermittent static. Moving an amp away from a signal generator can remove these noises.


It’s also a good idea to make sure the tubes are properly socketed, that can generate some noise as well

Edit* missed Andy’s post above noise, he would be much better at explaining than I


----------



## Pictograms

Since I brought this up I am interested if different varieties of tubes have different propensities for noise? 
If I roll EL34 for example are they more temperamental than KT88? Or are all tubes about the same?


----------



## GU1DO

Fatdoi said:


> I think HA6A is on different level to HA1A.... i will consider it's top end HP amp for those who don't prefer 300B..... once the hissing issue is sorted.


If you can describe the 300B sound in comparison to other tubes that would be helpful, 
if i need to ship my HA6A to Cayin i may ask to exchange it to HA300


----------



## IPMano

I delete my request, i waiting.


----------



## Gr3g277 (May 30, 2020)

hello guys,

Long time reader, not much post here, but I am an avid hifi and headphone enthusiast
I received my HA-6A juste a few days ago, and I am still in the burn-in phase.

What I can say now is that this amp sound really amazing, but as a diva, it is exigeant with the setup...
What a beauty !
pics or it didnt't happen 





I have 3 headphones to use it with :
- hifiman ARYA
- sennheiser HD650
- Kennerton Magni

I tested 3 dacs with it:
-marantz hd dac 1
-topping dx3prov2
-schiit bifrost 2 ( retrieved from the main hifi system for testing puposes )

First I will not comment on the sound just yet, because it is still not burned in fully yet, and well, i am not fully decided on the tubes..., but I can already say that the sound quality is very much to my liking...

I read the entire thread, and noticed some of you are experiencing issues with noise and/or hiss.
I would like to share my experience with this beast.
First, I am in france so my unit is 230V/50hz . I planned to use the amplifier for my computer rig, so digital only. First try was with my hd650, connected via RCA to the marantz dac, and usb to the PC....
This was not so good... lots of very loud noise, i could hear blips and high ptiched noise... something was definetely wrong here!
the amp was grounded to the power plug properly, good connection with the rca to the marantz DAC, but it was really unlistenable at first, I was puzzled ! I tried switching dac, with the topping, same problem ! then I scavenged the bifrost 2 from the living room to try a balanced connection.

Strange pc Noise was gone ! and the unit was silent ! ( almost... more on that later )

I understood from my testing that this amp, with all the power available, is very sensitive to grounding...

The bifrost 2 is grounded to the mains...not the other two dacs, so they were connected to the ground via the USB plug on the pc, which is connected to the ground. So there was a ground loop with the PC Usb cable and the rca connector... I confirmed this by connecting an optical cable between the marantz dac and the noisy pc, thus eliminating the shared ground from those two = bingo ! silence !

Now we can talk about the hiss issues you guys are talking about.
I tested with the arya, no problems whatsoever, regardless of the impedance settings, sounds gorgeous
with the hd650 however, on the high impedance setting, I don't get hiss, but I get HUM, very noticeable. on the low impedance, hum is almost non existent.

I think it is related to the very high power the amplifier gives to a 300ohm load.... or maybe to much gain ? with xlr IN in can turn the volume 3 cliks and i have loud music already !

The preamp part is very sensitive to the quality of your tubes as well, I tried NOS 5814a RCA blackplates, JJ ECC802S and the 12au7 from my primaluna main amp , and the quietest one is actualy the original EH that comes with it.
I get hiss and microphonics with the NOS 5814a and low hum, no hiss or microphonics with JJecc802s but louder HUM ! so my advice is check your preamp tubes !

I have some 6189 and 6L6 on the way, i'll report back when I get them !

Also i have a question, how hot does the power transformer get on your devices ? on mine After 2h of playing, I can barely touch it ! I know it is Class A but it feels really hot ! much hotter than my primaluna for exemple.


here is my first experience, I think it is a great amp but It need some work to give the best.

regards


----------



## IPMano

Bonjour,

Je vais écrire en français car j'ai trop de peine avec l'anglais, tu l'a reçu il y quelques jours ? il vient de chez Son-Vidéo ?
Le 18 mai il était de stock, je le commande, je le paye et quand je vérifie le lendemain il n'est plus de stock je me dis ok il n'y en avait qu'un, mais pas pour moi, quelqu'un est passé juste quelques minutes avant moi pour le paiement, ne serait ce pas toi ?

Il me plait vraiment, j'ai déjà le HA-1A MKII donc ça va je peux attendre surtout que demain matin je vais chercher un Euphoria.

Bonne écoute.


----------



## Gr3g277

Bonjour IpMano !
En effet c'est bien moi... je l'ai commandé le 18 aussi ! Désolé d'avoir été plus rapide, je l'ai recu ce mardi 
J'ai lorgné sur l'euphoria aussi mais je mebsuis tourné vers le ha-6a car je voulais pouvoir driver autant mon magni que mon hifiman .
De plus j'ai deja une petitz collection de tubes compatibles avec ce modèle,  venant de mon primaluna prologue classic dans le système du salon !
Si tu es pas loin de la region de metz, tu seras le bienvenu pour ecouter la bête


----------



## IPMano

Bonjour Gr3g277

Tu l'as reçu que mardi ? ça été long la livraison.
J'ai eu de la malchance, je l'avais commandé le 17 une 1ere fois mais mon paiement avait été refusé, je ne comprenais pas pourquoi et quand ton paiement a raté il faut refaire la commande, ça je le savais pas j'ai cherché et cherché pour voir comment refaire le paiement, pour finir j'ai contacté le service clientèle, j'ai donc refait la commande le 18 et de nouveau paiement refusé, j'ai contacté ma banque, je payais via paypal et j'avais reçu il y a 2 mois une nouvelle carte, je devais donc mettre à jour ma carte dans paypal, chose faite allez hop 3eme commande paiement accepté, le 20 toujours pas envoyé je les contact et voilà plus de stock.

C'est vrai que c'est du costaud, mon HA-1A MKII déjà a de la réserve, j'ai pas dépassé mi course du volume, ce qui m'ennuie c'est le très faible ronronnement, si je met la sélection sur 8-32ohms on ne l'entend plus, au fur et à mesure qu'on monte ça devient plus fort tout en restant trsè faible, j'ai bien l'impression que c'est du 50hz.
Ce HA-6A m'a fait peur avec ce problème de sifflement j'ai donc annulé ma commande pour finir et comme par hasard te voilà ^^
Je regardais beaucoup sur FB sur audiophile détendu pour voir si je voyais pas qqun montré son nouveau joujou.

Avec le peu d'écoute que tu as dessus en es tu content ?

Je suis de Belgique région de Charleroi c'est pas tout près.

Je vais me préparer pour aller chercher le Feliks à Bruxelles.

Bonne écoute et bon Week End


----------



## Zachik

@IPMano and @Gr3g277 - guys, *Head-Fi rules call for English posts only!*
I see you're both very new users, so I assume you were not aware...


----------



## Relaxasaurus

Zachik said:


> @IPMano and @Gr3g277 - guys, *Head-Fi rules call for English posts only!*
> I see you're both very new users, so I assume you were not aware...


That's really a rule? I wish there was a translate button after each post


----------



## Zachik

Relaxasaurus said:


> That's really a rule? I wish there was a translate button after each post


"The language of Head-Fi is English. Please do not post in other languages." - see:
https://www.head-fi.org/articles/posting-guidelines.14048/


----------



## IPMano

Sorry, but just between Gr3... and me, not important message and i've begin
if i speak english like a spanish cow, sorry.


----------



## Zachik

No worries. BTW, you guys can always use PMs (Private Messages) in ANY language you feel like


----------



## Gr3g277

Ok i was not aware of that sorry !
Basically we ordered the ha 6a at almost the same moment,  an unfortunately for ipmano, i was the fastest... 
It is not very widely available in france yet, it seems !
@Zachik i didn't know about the pm feature thx for the clarification 

To get back on the topic, i feel like the hiss issue you guys are talking about, is 50/60hz hum ?

With the hd 650 it is quite noticeable on the high impedance setting... jdut like when you turn on a big ass tube guitar amp with loads of gain !!

I know a bit about tubes , and the choice of the 12 au7 should be silent, as it is a low amplification factor tube.

For instance the 12 au7 amp factor is around 20, where a 12 ax7 in exemple is around 100.

Wondering what is happening here !

Nevertheless, the guitars are soo textured,  i love it


----------



## Andykong

Gr3g277 said:


> hello guys,
> 
> Long time reader, not much post here, but I am an avid hifi and headphone enthusiast
> I received my HA-6A juste a few days ago, and I am still in the burn-in phase.
> ...



Thank you for your sharing, your experience is very helpful to fellow HA-6A users and tube headphone amplifier users in general.  

USB Audio cable is a known source of interference, it can be a ground loop problem as you have encountered, or it can be a back cable design that doesn't provide proper insulation between the power wire and the data wires. 

Some tubes are more sensitive to RF interference than other, its is not necessarily a bad tube, just a design issue that make is less suitable for high end audio application.


----------



## Little Bear

Does anyone think the HA-6A would be able to drive the Hifiman Susvara or HE6se without any issue?  Both are low impedance planars with about 83 dB/mW sensitivity.


----------



## Andykong

Little Bear said:


> Does anyone think the HA-6A would be able to drive the Hifiman Susvara or HE6se without any issue?  Both are low impedance planars with about 83 dB/mW sensitivity.



According to @GU1DO,  HA-6A can power HE6se easily  (*HERE*)


----------



## Gr3g277

Hey guys,

just a quick update to let you know that I received some Jan 6189, and that i'm loving those tubes 

Still enjoying the amp a lot with my arya, and i'll give my listening impressions in a while, when I will be more used to the unit. ( I have quite some tubes to test lol )

I was wondering about the resistor change that @Relaxasaurus  was talking about , any news about that ? I can help as well, if needed as i am an engineer.

I also have some questions for @Andykong :

-we already know that changing the impedance switch affects the ouptut power of the amp , but how does it affect the output impedance ? do you have numbers for output impedance for all the modes ? for example, if listening to a 300ohm can on L impedance switch, is it bad for the amp ? what about the other way round ?

-The VU meters , how are they calibrated ? do they monitor the input signal only ? or are they related to the output power as well ? I can tell that they do not behave similarly when using different headphones ( I had them maxed with the arya already, not with the hd650 unless unconfortably loud ).

best regards


----------



## Andykong

Gr3g277 said:


> Hey guys,
> 
> just a quick update to let you know that I received some Jan 6189, and that i'm loving those tubes
> 
> ...



The output transformers of HA-6A were specially winded to provide three set of _impedance_ _match_ed outputs at 8-64Ω, 65-250Ω, and 251-600Ω respectively, the exact impedance might vary but basically they are somewhere around the mid-value of these ranges.

The VU meter is reporting the current output power, it is a linear proportion of the output in Vrms (not watt per channel).  

The HiFiman Arya has a much lower sensitivity then HD650, so despite the HD650 is rated at 300ohm impedance, the actual power required to drive the Arya at your regular sound level is HIGHER then the power required to drive the HD650 at the same sound level, so the VU meter will swing closer tot he red area when driving the Arya.


----------



## Relaxasaurus

Gr3g277 said:


> I was wondering about the resistor change that @Relaxasaurus  was talking about , any news about that ? I can help as well, if needed as i am an engineer.


I mailed the HA-6A to a repair center in Arizona on Cayin's dime, on May 29. It's been almost a month but AFAIK it's still at the repair shop.

I luckily have the WA22 to keep me company but that's about all the news I have.


----------



## wazzupi

I'm torn between this unit and the pendant!!


----------



## Celty

Relaxasaurus said:


> I mailed the HA-6A to a repair center in Arizona on Cayin's dime, on May 29. It's been almost a month but AFAIK it's still at the repair shop.
> 
> I luckily have the WA22 to keep me company but that's about all the news I have.


What is the problem with such a new amp?


----------



## Relaxasaurus

Celty said:


> What is the problem with such a new amp?


I was getting hiss and the repair guy is checking it out. It may involve a simple resistor change but not sure exactly.


----------



## wazzupi

Relaxasaurus said:


> I was getting hiss and the repair guy is checking it out. It may involve a simple resistor change but not sure exactly.


Did the the hiss ever turn to ppppsssstttttt hehe


----------



## wazzupi

I think I'll be waiting til this issue has been resolved to purchase my next tube amp. But this amp is a strong contender.


----------



## kimdeug (Jul 15, 2020)

Relaxasaurus said:


> Really fun Sunday so far





Relaxasaurus said:


> I was getting hiss and the repair guy is checking it out. It may involve a simple resistor change but not sure exactly.



Thank You my Friend for support and good video.
As result my 5 cents to this topic.
My unit has arrived 15 minutes ago from this typing.
Still do unpacking.
Very excited
Regards from New Zealand,
Kim


----------



## Fatdoi

kimdeug said:


> Thank You my Friend for support and good video.
> As result my 5 cents to this topic.
> My unit has arrived 15 minutes ago from this typing.
> Still do unpacking.
> ...


love to hear the review on your new baby.... it's been bit quiet on this thread


----------



## kimdeug (Jul 17, 2020)

Fatdoi said:


> love to hear the review on your new baby.... it's been bit quiet on this thread



Thanks Fatdoi
Sure will do soon.
Will burn it 24 hours on stock tubes and have a look for hiss noise from 4 pin XLR out on Dynamic headphones.
Source: MacBook Pro 15">> Ifi micro iUSB3.0 >> SMSL SU-8 >> Cayin HA-6A
Headphones (my collection):   Audeze LCDX, LCD2C; Sennh HD800s, 660s, 6xx, 58x, PC36xd; Beyerodynamic DT-1990 pro, Amrion Wireless; Focal Elex, Monolith M1070c and M570; AKG 7XX, Q701; Sendy Aiva; Fostex T50, T60, Argon MK3, 00x Ebony; ZMF Auterus, Sony MDR-7; Philips X2; Mr Speakers Either CX etc. etc. etc


----------



## iFi audio (Jul 16, 2020)

kimdeug said:


> Source: MacBook Pro 15" >>*Ifi micro iUSB3.0* >>SMSL-SU8 >> Cayin HA-6A



If I may ask, how does it work for you in your setup?

And nice set of LS50 you have in there!


----------



## Gr3g277 (Jul 16, 2020)

wow !

This my friend , is an impressive collection !

I am playing with tubes with mine, 6L6WGC-str blackplates at the moment , JAN Sylvania 6189, rca 5814A, JJ ECC802S...
I love how the amp sounds, and how responsive it is for tube rolling


----------



## kimdeug (Jul 17, 2020)

iFi audio said:


> If I may ask, how does it work for you in your setup?


It works beautiful. May be from laptop it is not so noticeable, as the battery works like power filter capacitors, but on other hackintosh computer (near left LS50 speaker) it does amazing job. Because USB shares the same ground, it is a big interference noise when moving the mouse or scrolling the web page, and also from the other USB devices, which are working like antenna and attract all sort of interference noise. After going throw Ifi micro iUSB 3.0 the signal is absolutely clean and dead silent. Plus separate clean DC power for USB supply.


----------



## iFi audio

Gr3g277 said:


> wow !
> 
> This my friend , is an impressive collection !
> 
> ...



Great photo! Lots of things going on in there color wise, very cool!



kimdeug said:


> It works beautiful. May be from laptop it is not so noticable, as the battery works like power filter capacitors, but on other hackintosh computer (near left LS50 speaker) it does amazing job. Because the USB shares the same ground, it is big interference noise when moving the mouse and from other USB devices, which are working like antenna and attracts all sort of interference noise. After going throw Ifi micro iUSB3.0 the signal is absolutely clean and dead silent . Plus separate clean DC for USB power.



USB cleaning is system specific, some devices benefit more than others, and laptops often have quieter USB outs. Thanks for sharing!


----------



## kimdeug (Jul 16, 2020)

Gr3g277 said:


> wow !
> 
> This my friend , is an impressive collection !
> 
> ...


Thank you.
This is a very nice warm glowing footage. Another beauty of tubes. I can watch it all night.  Planning tube rolling too in the future (GEC KT66 and KenRad 6L6) drivers Lorenz ECC82. But now, just had unpacked the amp, had made few pictures and uploaded here to share my excitement. As I had only 20 minutes before my work started, I had only checked the delivery. If everything is OK, even did not plug it yet. I am at work now and waiting the end of the shift to play with my new beauty at home. Regards, Kim


----------



## kimdeug

love to hear the review on your new baby.... it's been bit quiet on this thread

Small update. It is 03:19 morning. Stock tube burning in progress. Has done around 24 hours. Can not do white noise burning as not at home almost all time. Only few hours early morning, before work. Needs more time to play with amp and different earphones and will post my thoughts here later. Regards, Kim


----------



## Relaxasaurus

Love seeing more of these amps out in the wild. 

Anyone else getting hiss on dynamic headphones?


----------



## kimdeug (Jul 24, 2020)

Relaxasaurus said:


> Love seeing more of these amps out in the wild.
> 
> Anyone else getting hiss on dynamic headphones?


Yes I have hiss too.It is more like combination of Hiss and Humm together. In proportion Hiss/Humm as 70/30. Hiss is gradually increases with increase of Volume, but much slower (not like sound increases), while the Humm noise almost reminds on the same level and with Volume increase, suddenly start to distort (depends of RCA or XLR input selected) at 1 or 3 o'clock respectively.  Right now I am using Sennheiser HD800S. Hiss/Humm on 4 pin XLR output in all L, M, H impedance positions. Hiss/humm starts to distorted when Volume at 3 o'clock (assuming that the Volume knob traveling from min 7 o'clock to max 5 o'clock position). I am using XLR input from DAC with max volume for me no more than at 9 o'clock position).
In my situation hiss/humm comes from all 1/4, pentagone, and 4pin XLR outputs. Looks like loud valves, but very noticeable when switching between headphone's outputs  on minimal volume.
Control test: Unplug everything. No any inputs. Only Power cable. Sennheiser HD800S plugged in into 4 pin XLR output. Hiss starts on the last 2-3 actuators steps on each L,M, H impedances.
Next test: RCA input from DAC. Music on pause. Hiss starts from 1 o'clock volume position, very loud on maximum volume on each L, M, H impedances.
Next test: XLR input from DAC. Music on Pause. Hiss starts from 3 o'clock volume position, noticeable hiss when volume on maximum on each L, M, H impedances again.
RCA input gives the most loud hiss. Usually I am using XLR input and at volume at 9 o'clocks it is inaudible. Will play with better shielded RCA and XLR cables tomorrow.

Also will play tomorrow with Power filtering, DC blocker, Power filter conditioner, good shielded power cable and will do very short run/cable from DAC. may be 3.0inch XLR and RCA with extra shielding.
Also will do more tube burning may be 100 hours.
Will post my results here.
At this moment try to exclude any other reason of hiss.


----------



## GU1DO

kimdeug said:


> love to hear the review on your new baby.... it's been bit quiet on this thread
> 
> Small update. It is 03:19 morning. Stock tube burning in progress. Has done around 24 hours. Can not do white noise burning as not at home almost all time. Only few hours early morning, before work. Needs more time to play with amp and different earphones and will post my thoughts here later. Regards, Kim


How is  Pathos Aurium in your setup ?
i am eyeing that amp for long time but i never pulled the trigger


----------



## GU1DO

Relaxasaurus said:


> Love seeing more of these amps out in the wild.
> 
> Anyone else getting hiss on dynamic headphones?


I was told that my HA6A is fixed and should arrive within the next few weeks


----------



## kimdeug (Jul 20, 2020)

GU1DO said:


> I was told that my HA6A is fixed and should arrive within the next few weeks


Please. Let us know what was the problem.
Seems, like I need to send my too. I have like hiss/humm sound on all 1/4, Pentagone, and 4 pin XLR at no any source plugged in. Only plugged power cable.
Humm/hiss noise is noticeable at minimum (Zerro) volume position, in all Impendances (L, M, H), and all planar and dynamic headphones especially when switching the output sources, lets say from 1/4 to XLR 4 pin (very big contrast from dead silence to a this humming/hissing noise, where headphone is plugged to 4pin XLR only).  Seems like this noise starts to be distorted, when increase the volume around 1 or 3 o'clock position (depends of impedance  position) again without any input cables plugged IN (only power cable).
Summary: In my case the humm noise happens in all my (planar and dynamic headphones) from all 1/4, Penta, 4pin XLR outputs and prone to be distorted at the higher volume 1-3 o'clock (depends from which Impedance is selected). Not sure  what is the problem. Noise/ distortion is not listenable for me. Will do investigation further. Kim


----------



## kimdeug

Andykong said:


> Let me help you to trace your case, I need the serial number of your HA-6A, will send you an PM to start the follow up process.


Hi Andykong.

Please contact me to PM.
Have the same issue with my Cayin HA-6A

Regards,
Kim


----------



## Fatdoi

kimdeug said:


> Please. Let us know what was the problem.
> Seems, like I need to send my too. I have like hiss/humm sound on all 1/4, Pentagone, and 4 pin XLR at no any source plugged in. Only plugged power cable.
> Humm/hiss noise is noticeable at minimum (Zerro) volume position, in all Impendances (L, M, H), and all planar and dynamic headphones especially when switching the output sources, lets say from 1/4 to XLR 4 pin (very big contrast from dead silence to a this humming/hissing noise, where headphone is plugged to 4pin XLR only).  Seems like this noise starts to be distorted, when increase the volume around 1 or 3 o'clock position (depends of impedance  position) again without any input cables plugged IN (only power cable).
> Summary: In my case the humm noise happens in all my (planar and dynamic headphones) from all 1/4, Penta, 4pin XLR outputs and prone to be distorted at the higher volume 1-3 o'clock (depends from which Impedance is selected). Not sure  what is the problem. Noise/ distortion is not listenable for me. Will do investigation further. Kim



Seems they still haven't addressed the hissing issue yet.... will see what they'll do about it..... hope they'll give us an update on the actual fixes


----------



## kimdeug (Jul 25, 2020)

Fatdoi said:


> Seems they still haven't addressed the hissing issue yet.... will see what they'll do about it..... hope they'll give us an update on the actual fixes


Yaa. Seems like has not fixed it yet. Any way in Auzee you have the daeler: https://a1futureshop.com.au/
And you can address all problems to them. In New Zealand it is more complicated. So, will try to eliminate all non amplifier related issues by myself and if not, the last  thing - I will send it back, I hope Andykong will help me with my unit. Kia Ora. Kim


----------



## Gr3g277 (Jul 20, 2020)

kimdeug said:


> Yes I have hiss too.  Right now I am using Sennheiser HD800S. Hiss or distortion on 4 pin XLR output in all L, M, H impedance positions. Hiss starts when Volume at 3 o'clock (assuming that the Volume knob traveling from min 7 o'clock to max 5 o'clock position). I am using XLR input from DAC with max volume for me no more than at 9 o'clock position).
> In my situation hiss comes from all 1/4, pentagone, and 4pin XLR outputs. Looks like loud valves, but very noticeable when switching between headphone's outputs even on minimal volume.
> Control test: Unplug everything. No any inputs. Only Power cable. Sennheiser HD800S plugged in into 4 pin XLR output. Hiss starts on the last 2-3 actuators steps on each L,M, H impedances.
> Next test: RCA input from DAC. Music on pause. Hiss starts from 1 o'clock volume position, very loud on maximum volume on each L, M, H impedances.
> ...



I replicated your tests on mine with my kennerton magni and my hd 650, with approx same results

I have a supra LO-Rad power strip and good power shielded power cables, I did not notice any differences in hum or hiss with it

Curious to hear if you have good results with a DC blocker, I was thinking about getting one as well !



kimdeug said:


> Please. Let us know what was the problem.
> Seems, like I need to send my too. I have like hiss/humm sound on all 1/4, Pentagone, and 4 pin XLR at no any source plugged in. Only plugged power cable.
> Humm/hiss noise is noticeable at minimum (Zerro) volume position, in all Impendances (L, M, H), and all planar and dynamic headphones especially when switching the output sources, lets say from 1/4 to XLR 4 pin (very big contrast from dead silence to a this humming/hissing noise, where headphone is plugged to 4pin XLR only).  Seems like this noise starts to be distorted, when increase the volume around 1 or 3 o'clock position (depends of impedance  position) again without any input cables plugged IN (only power cable).
> Summary: In my case the humm noise happens in all my (planar and dynamic headphones) from all 1/4, Penta, 4pin XLR outputs and prone to be distorted at the higher volume 1-3 o'clock (depends from which Impedance is selected). Not sure  what is the problem. Noise/ distortion is not listenable for me. Will do investigation further. Kim



The hiss with high volume position does not really bother me, because the max I went with my (hard to drive, low sensitivity 90db/mw) hifiman arya is about 12 o'clock, and that is REALLY Loud.
with hd 650 and magni ( around 104db/mw ) 9 o'clock is plenty loud, 10 is really loud ( using schiit bifrost2 XLR as source )

What's more bothersome to me is the noise floor with my sensitive headphones. WIth the magni, at 32 OHM; impedance set to L, volume at min, I can barely hear as tiny white noise. If I raise the impedance setting to High, the white noise is now pretty distinct , but this is not how you are supposed to use it

With the hd650, Impedance setting to H , I can hear the white noise clearly.... so not really using them at the moment.
I wanted to get a set of utopia's, but the high sensitivity cold me down a bit

With my arya , no matter the impedance setting, everything is dead quiet

On the other hand, you were mentionning distortion, and I can't hear any , no matter how hard I am trying... I can turn my arya's into small speaker with that thing 

The preamp section is really sensitive to tube quality as well, some tubes are noisier than other. But Everything I sayed here was after selecting the quietest tubes. ( the OG 12au7 EH and JAN Sylvania 6189 were the quietest from my tube stash I got from my primaLuna)

That said, this amp sounds great, and I really enjoy it with all the firepower it can give to my arya's !
I hope this noise/hiss issue can be solved easily,and waiting for the results .


----------



## kimdeug (Jul 20, 2020)

GU1DO said:


> How is  Pathos Aurium in your setup ?
> i am eyeing that amp for long time but i never pulled the trigger


    Pathos Aurium is a great Italian piece of art. I have bought it for 1/3 of price second hand. Selectable direct out is very convenient option, as can work on standby and redistribute all signals from all inputs and outputs. It is heavy and full of hardware inside (not like CTH from MD). On official website it has been mentioned output 3.6W at 16 Ohms, but from my measurements it is more like 1.8W. It means: It is quiet and not very powerful. Sennh. 6XX on volume 70% for normal listening.
    Inside it is full balanced design, as result very nice 3 dimensional soundstage. Dead silent, no any distortions, background noise, hissing, humming, buzzing etc. Good response for driver tube rolling 6922 family. I am using Siemens CCa now. But Russian 6N23 Reflector 65-77 are very good too and 100 times cheaper than CCa. Have around 200 different 6922 tubes (E88CC, E188CC, E288CC. Mullard CV2492 or CV2493, 7308, PCC89 etc). The same tubes as for CTH and  monoprice Liquid platinum (MLP). Soundwise it is  more lush than CTH and MLP but all details are present and even more clear. But it sounds more like tube amp.
    I will keep Aurium in my collection, as I really like the Pathos Aurium sound signature and will utilise my 200 tubes), but for you I will suggest the second hand unit for the half price, as this is a 2013 model and there are a lot of competitors for the same full price. Definitely, for me it sounds much  better than MLP. That is why I sold my MLP and keeping Aurium. Custom power supply does not change too much in terms of sound quality so,don't waist the money and keep the original one.

    Regards,
    Kim


----------



## GU1DO

kimdeug said:


> Please. Let us know what was the problem.
> Seems, like I need to send my too. I have like hiss/humm sound on all 1/4, Pentagone, and 4 pin XLR at no any source plugged in. Only plugged power cable.
> Humm/hiss noise is noticeable at minimum (Zerro) volume position, in all Impendances (L, M, H), and all planar and dynamic headphones especially when switching the output sources, lets say from 1/4 to XLR 4 pin (very big contrast from dead silence to a this humming/hissing noise, where headphone is plugged to 4pin XLR only).  Seems like this noise starts to be distorted, when increase the volume around 1 or 3 o'clock position (depends of impedance  position) again without any input cables plugged IN (only power cable).
> Summary: In my case the humm noise happens in all my (planar and dynamic headphones) from all 1/4, Penta, 4pin XLR outputs and prone to be distorted at the higher volume 1-3 o'clock (depends from which Impedance is selected). Not sure  what is the problem. Noise/ distortion is not listenable for me. Will do investigation further. Kim


I had the same issue as you ,, hiss very clear with dynamics little with planers, beside that last day there was another problem with the power with one of my dacs , but i think it was glitch and am not sure about it , Anyway i had to ship it (on my expanse) to Germany because no dealers in my country, and last week i was informed they fixed it and now its on the way but it will take little longer than expected.


----------



## GU1DO

kimdeug said:


> Pathos Aurium is a great Italian piece of art. I have bought it for 1/3 of price second hand. Selectable direct out is very convenient option, as can work on standby and redistribute all signals from all inputs and outputs. It is heavy and full of hardware inside (not like CTH from MD). On official website it has been mentioned output 3.6W at 16 Ohms, but from my measurements it is more like 1.8W. It means: It is quiet and not very powerful. Sennh. 6XX on volume 70% for normal listening.
> Inside it is full balanced design, as result very nice 3 dimensional soundstage. Dead silent, no any distortions, background noise, hissing, humming, buzzing etc. Good response for driver tube rolling 6922 family. I am using Siemens CCa now. But Russian 6N23 Reflector 65-77 are very good too and 100 times cheaper than CCa. Have around 200 different 6922 tubes (E88CC, E188CC, E288CC. Mullard CV2492 or CV2493, 7308, PCC89 etc). The same tubes as for CTH and  monoprice Liquid platinum (MLP). Soundwise it is  more lush than CTH and MLP but all details are present and even more clear. But it sounds more like tube amp.
> I will keep Aurium in my collection, as I really like the Pathos Aurium sound signature and will utilise my 200 tubes), but for you I will suggest the second hand unit for the half price, as this is a 2013 model and there are a lot of competitors for the same full price. Definitely, for me it sounds much  better than MLP. That is why I sold my MLP and keeping Aurium. Custom power supply does not change too much in terms of sound quality so,don't waist the money and keep the original one.
> 
> ...


That was more than i wanted to know , i appreciate your time and feedback , Thank you


----------



## kimdeug

GU1DO said:


> I had the same issue as you ,, hiss very clear with dynamics little with planers, beside that last day there was another problem with the power with one of my dacs , but i think it was glitch and am not sure about it , Anyway i had to ship it (on my expanse) to Germany because no dealers in my country, and last week i was informed they fixed it and now its on the way but it will take little longer than expected.


Good news, congrats. Only the real owner can feel what does that news mean.  If it possible to get any info from repair person, it will be very helpful and highly appreciated.  Now  I am only guessing and playing around what is wrong.
Will do some investigation test  this week and publish my finding here. Regards, Kim


----------



## GU1DO

kimdeug said:


> Good news, congrats. Only the real owner can feel what does that news mean.  If it possible to get any info from repair person, it will be very helpful and highly appreciated.  Now  I am only guessing and playing around what is wrong.
> Will do some investigation test  this week and publish my finding here. Regards, Kim


Thank you ,, will give feedback once i have it ,, Cayin never disclosed what was fixed in there repair center ,  i guess they updated the amp with new parts or somthing , am not sure , hopefully it keep being as powerful as before because it is really good to have a tube  amp that can power heavy headphones like the HE6se.


----------



## Fatdoi

kimdeug said:


> Yaa. Seems like has not fixed it yet. Any way in Auzee you have the diller: https://a1futureshop.com.au/
> And you can address all problems to them. In New Zealand it is more complicated. So, will try to eliminate all non amplifier related issues by myself and if not, the last  thing - I will send it back, I hope Andykong will help me with my unit. Kia Ora. Kim



I've bought some gears from A1... they used to have a shop but now a home based business so there's no demo on anything.... this hissing issue worried me quite a lot as i see this amp as my ideal tube amp for my cans...

so would like yours and others input on the return (fixed) units and see if they have really fixed the problem..... thanks in advance


----------



## kimdeug

Fatdoi said:


> I've bought some gears from A1... they used to have a shop but now a home based business so there's no demo on anything.... this hissing issue worried me quite a lot as i see this amp as my ideal tube amp for my cans...
> 
> so would like yours and others input on the return (fixed) units and see if they have really fixed the problem..... thanks in advance


Thanks for info. Good to know about this. I was very close to order HA-6A via A1 shop, but ended up with local dealer in NZ.
Collecting all equipment to conduct some investigation test: Power filter, DC blocker, Good shielded power cables, handmade short XLR etc.
Will do some experiments and will post results here on weekend. Still waiting replay from Andykong..........Regards, Kim


----------



## kimdeug

Andykong said:


> To be exact, this problem. hiss on XLR4 outputs when using dynamic headphones,  only appear on @Relaxasaurus unit,  this is the first instance reported and we are studying it closely.  We haven't encountered any other case that exhibit similar problem.  We are working with Andrew from Musicteck to resolve this problem, unfortunately Andrew sold his demo unit recently, otherwise they can send a demo unit to Relaxasaurus for crosschecking and as temporary replacement.


Hi Andykong.

Please, contact to me on PM. 
I have the same issue with my Cayin HA-6A

Regards,
Kim


----------



## Fatdoi

kimdeug said:


> Hi Andykong.
> 
> Please, contact to me on PM.
> I have the same issue with my Cayin HA-6A
> ...



I'm reading the HA300 thread and some users still have humming issues which Andy still trying to debunk.... which i'm curious regarding Cayin's quality of design towards their headphone amps....


----------



## kimdeug (Jul 23, 2020)

*TERMINOLOGY*

Hi all Cayin HA-6A lovers.

While waiting response from Andykong try to do some trouble shooting by myself. But before, I have looked through my previous posts and have found a lot of inaccuracy in description of noise coming out from Ha-6A.

In this post I want to do some clarification in terminology used. Hope it will help for better understanding and be sure that we are talking about exactly the same things. Lets start.....

Noise by type of sound (*Hiss, Humm, Buzz)

Hiss *(Hissing noise) - Sibilant sound without any tonality. Sounds like Ss_Ss_Ss_Ss_Ss or like Sh_Sh_Sh_Sh_Sh.Similar like switching the stations on old radio. Can be only measured by level  of loudness (amplitude).

*Humm* (Humming noise) Has own tonality. Sounds like Mm_Mm_Mm_Mm_Mm. Looks like sound from working transformer and can be measured by level of loudness and tonality (Ex.50-60Hz)

*Buzz* (Buzzing noise) - combination of  Hiss and Humm noises. From here, have both characteristics to measure. In addition, the proportion of Hiss to Humm can be varied. As result, depends of proportion, it could be sound like Zz_Zz_Zz_Zz_Zz or like Zh_Zh_Zh_Zh_Zh.  Or can be as two separate Humm and Hiss sounds at the same time. (In my situation exactly as two separate simultaneous sounds Humm/Hiss in proportion 30/70%).

*Zero Point - *is a reference point of Zero noise. Equivalent of physically unplugged headphone cable from your headphone amplifier. Broken (unplugged) circuit, no any current goes through the headphone cable, as result absolute silence. In Cayin Ha-6A instead of plug/ unplug headphone cable we can use output switch (1/4, Penta, XLR) to brake the circuit.

Noise by location (*White, Background (all variants)*)

*White Noise -* is a noise, which has been produced by (headphone) amplifier itself only. It means NO any signal cables connected to the amplifier input XLR or RCA. Only power cable to operate. So, from here white noise can be affected by Quality/clarity of supplied power and amplifier's internal hardware/parts (tube interference).

*Background Noise* - is a combination of White Noise + All noises coming IN via connected XLR or RCA Input cables to (headphone)amplifier from all peripheral equipments (Computer, DAC, Phono Stage, Mixers, Processors etc) including DC loop noise, all sort of interference noise. in other words It is a summ of White Noise + All noises produced outside of amplifier.
In real life if you are listening music on computer via DAC >> Headphone Amp>>Headphone and press music on PAUSE you will hear this noise.
Originally Background noise is the noise which is recorded on original music tracks (vinyl etc), but in our case we are more interested in Cayin Ha-6A amplifier faults, so will put all external (out of amplifier) noises in this category.

*Initial Noise *_-(quantity characteristic) _is *amount of any noise at minimal (zero) Volume*. Some times (in good/not faulty amplifiers) it is hard to hear it audibly (only can be seen on oscillators on amplitude zooming), so needs to increase the volume to hear it, but need to mention the volume position when it happens. In my case, initial noise is very noticeable at Zero volume.
In my situation, switching between Zero Point to any plugged Headphone output with different Impedances, makes Initial Noise so noticeable and almost unlistenable for music. Which destroys all concept of headphone music listening. This is a main reason of my complain about HA-6A.
Do not take me wrong. I really like the sound coming out from HA-6A, but this *White Noise *and *amount of initial Noise* are killing all joy of this 2500$ experience.

*Distortion* - at the presence of Initial Noise try to increase Volume. In some point the  loudness of noise from linear progression/increases will suddenly jump non-proportionally louder (exponentially). At the same time it will bring new harmonics and tonality, which is very audible. After this point the next Volume actuator step will increase previous volume level almost as double.
In my previous posts I have mentioned this Distortion as Hiss starting on 1-3 o'clock depends of RCA or XLR input, and Sensitivity selected.

I think the most important parts are  covered.
If something is missing, please reply with your suggestions.
I am not a professional electrical person, just little above basic knowledge.
The practical part is coming soon....
Regards,
Kim


----------



## kimdeug (Jul 23, 2020)

Gr3g277 said:


> I replicated your tests on mine with my kennerton magni and my hd 650, with approx same results
> 
> I have a supra LO-Rad power strip and good power shielded power cables, I did not notice any differences in hum or hiss with it
> 
> ...



Hello my Friend.

Really appreciate your efforts to replicate my tests and share your findings.
At this moment I have canceled order of 6L6 and KT66 tubes, until the hiss issue will be solved.
But I am very curious how 6L6 tubes sounds like, compare to stock KT88 or EL34?
Also, please, look my previous post with *Terminology*.
I was in the same boat and was thinking: _"OK, I am only using 6XX at 9 o'clock volume maximum, and the hiss is not so noticeable. May be I will keep like this?"_
But, when I have done *Initial Noise Test *(6XX, 4 pin XLR out, High Impedance, Music on PAUSE) and compared to *Zero Point*, I have found that this *Hiss/Humm *noise was so loud!!! It was on all outputs: 1/4, Penta, 4pin XLR  (slightly less on 1/4, but still very audible). At Volume position 9 o'clock (for normal volume listening), we are talking about this amount of hiss noise coming to your headphone on top of the sound from music track. And this is unacceptable for me.
So, doing further investigation, while waiting response from Andykong.

Regards,
Kim

PS: Also you can do *Initial Noise Test *for *White Noise,* to see how much exactly noise your amplifier produces by itself.


----------



## kimdeug (Jul 25, 2020)

*White Noise Test*

Hello  Cayin HA-6A lovers.

Finally have got little bit time, so have conducted some tests to investigate the hissing issue on HA-6A.
To eliminate all speculations about dirty signal coming IN, this test has been conducted without any audio inputs XLR or RCA connected. Means: No any input cables has been plugged to HA-6A, except power cable to operate. In this situation, I tried to create the most ideal for HA-6A operation room environment, with attention to Clean power supply. OK, Lets do the White Noise Test......

*Equipments:*  Ha-6A, Power Filter Belkin PureAV PF40, Heavily Shielded Power Cables KRELL 20A, DC Blocker Supra MD Mk3
Headphones: Sennh HD800S, 6XX, ZMF Auteur, Focal Elex, Sony MDR Z-7

*Room environment:* All electronics are plugged OFF (except the lighting), Wi Fi is off, Mobile phone in the next room.

DC Block >> Power Filter >> HA-6A >> Headphones

*Results:*  In my situation, adding or removing the power filter and DC blocker from the power chain has not changed the noise coming out from HA-6A. It means no any changes in tonality, loudness, and character of noise - all was the same. The same about Heavy shielded power cables.
The noise can be described as *combination of Humm and Hiss* in proportion (Humm/Hiss) as 20/80 or 30/70 at Volume position Zero/Minimum*.*
The noise becomes louder with increasing the Volume.
The humming noise does not increase with hissing noise.
While* Hissing noise *increases linearly with Volume Up (but much slower), *Humm noise*  remains at the same level, and only with Volume around 3 o'clock, suddenly becomes more loud and creates distortion.
The noise was present at all impedances and all outputs.
The noise was more noticeable/louder on high impedance and XLR output selection,while on 1/4 and Low impedance was the lowest.
Switching from Triode  to Ultra-linear mod, made the noise more louder.
Low sensitivity headphones made the noise less noticeable.
Only one Volume step above zero makes 6XX sound loud. Next 3 steps -  too loud. Other 21 actuator steps are not usable on Hi Impedance for 6XX, HD800S and ZMF Auteur.

*Conclusion:* At this stage it is clear that the source of Hissing noise is coming out from Ha-6A and not related to the power supplied. Very high gain does not benefit  hi impedance headphones to shine. In opposite, it brings distortion on the last Volume actuator steps. By the character of noise, I can assume, it relates to Transformer power filtering and impedance matching issues, probably before amplifying stage.
The presents of noise is very audible and unacceptable for this price range equipment. Looks like you are listening music via old radio with all existing interferences.
In this stage I will pack the unit and will send it back to the dealer tomorrow.

Regards,
Kim


----------



## dpump (Jul 23, 2020)

Regarding the noise issues being discussed here. When you want to test any amp to see if the amp is generating noise itself, you cannot, repeat cannot, unplug all inputs, connect headphones, and then turn up the volume. You need to have shorting plugs in the inputs you are testing. An open or unloaded input will always cause you to hear more noise than the amp is generating by itself. I'm very surprised Andy Kong and Cayin haven't mentioned this. You need RCA shorting plugs and XLR shorting plugs to do the noise tests you are performing to be sure hiss is coming just from the amp.

Another thing is the impedance and sensitivity of the headphones you are using. Unfortunately, in my view, there has been a race by manufacturers in recent years to make their headphones or iems more and more efficient so they can claim that any source from a computer, phone, dap, portable amp, etc, can properly drive their phones. When you connect higher sensitivity and/or low impedance phones you will hear more noise. Connect a 93dB headphone and you have little to no noise. Connect a 100dB headphone and, no surprise, you hear more noise. Iems often go up to 110dB sensitivity or more so can be unusable on many amps due to noise. You have to take into consideration the specifications of the phones you are using when you are testing any amp for noise.

High and higher output power from headphone amps. There also seems to be the expectation now that amps should have as much output power as possible. We're up to 3 watts, 5 watts, 8 watts and more. There are almost no headphones that need this kind of power. The more power you have from an amp, especially tube amps, the more noise you can have. To some extent, you can't have a lot of power on a tube amp and expect to hear no noise of any kind. Tube amps will almost have more noise than solid state amps, although lower power tube amps can often be very quiet.

Bottom line, you should expect to hear some noise from Cayin amps using KT88, EL34, 300B, and EL84 power tubes when they have been designed to output multiple watts of power. These output tubes were originally designed and used to power speakers before headphones were even in use the way we are using them. All of these can be great sounding tubes, but in some sense are being used outside of the use they were designed for. I own a number of tube headphone amps, including the Cayin HA-1A MK2. My Cayin does have some hiss and noise with high impedance/high sensitivity headphones, but almost none with lower impedance phones. Other amps I have with less than 1 watt output have little noise. So don't expect to have no noise on a higher power tube amp. Tubes are inherently noisier than solid state and designing a tube headphone amp with a high output level, no matter what power tubes are being used, will pretty much guarantee you will have some audible noise depending on the headphones you are using.

I'm not saying that there might not be something in the design of the Cayin amps that is causing some of the noise. That may be the case. A possible fix could be to lower the gain somewhere in the amp, but I tend to think the Cayin is designed for the best possible sound and some noise is a result of their design choices. It will be interesting to see if Cayin makes any design changes and then discusses them here so owners can decide if they want to make any changes themselves.


----------



## kimdeug

dpump said:


> Regarding the noise issues being discussed here. When you want to test any amp to see if the amp is generating noise itself, you cannot, repeat cannot, unplug all inputs, connect headphones, and then turn up the volume. You need to have shorting plugs in the inputs you are testing. An open or unloaded input will always cause you to hear more noise than the amp is generating by itself. I'm very surprised Andy Kong and Cayin haven't mentioned this. You need RCA shorting plugs and XLR shorting plugs to do the noise tests you are performing to be sure hiss is coming just from the amp.
> 
> Another thing is the impedance and sensitivity of the headphones you are using. Unfortunately, in my view, there has been a race by manufacturers in recent years to make their headphones or iems more and more efficient so they can claim that any source from a computer, phone, dap, portable amp, etc, can properly drive their phones. When you connect higher sensitivity and/or low impedance phones you will hear more noise. Connect a 93dB headphone and you have little to no noise. Connect a 100dB headphone and, no surprise, you hear more noise. Iems often go up to 110dB sensitivity or more so can be unusable on many amps due to noise. You have to take into consideration the specifications of the phones you are using when you are testing any amp for noise.
> 
> ...


Hi, Thanks for reply.
I have done this test with no signals to avoid any discussion about noise which is generated outside of amplifier. This method has been chosen because, after connecting any DAC via XLR and RCA cables, the initial noise has been multiplied almost double in XLR and roughly triple at RCA connection at Zero Volume position.
Regarding to different impedance and sensitivity for each headphones: for this purpose I have deliberately listed the headphones used, and choice of each was specifically chosen because of different impedance and sensitivity. Also I have connected HA-6A via XLR to the X Grace design balanced DAC, which was powered via USB from laptop working on Battery only, with the same noise effect.
30% of Humm noise reminds me situation when I had WA-6SE Humm issue, but solution was very easy: you need to remove the  power block away  from amplifier block. Here it is not possible.
70% Hiss was hard to define why. First, I was thinking due to loud tubes, but after burning them around 70 hours all the same. Going further I have rolled them to used GEC88 tubes from my friend (just have took from his daily working amplifier) -with the same Hiss effect. Also rolled the driver with Lorenz  E82CC tubes, and hiss is still there.
From early discussions the original ElectroHarmonics 12AU7 are the quietest. It is obvious that more sensitive headphones are prone to pick up more noise, but early Andykong mentioned that with 300 Ohms headphones (Sennheiser HD800S and 6XX) Ha-6a suppose to be dead silent.
This is a not my first tube amplifier. I have Darkvoice, LaFigaro339 and Bottleneck Crack Speedball around, but all of them do not produce this amount of hiss/humming noise at  any Volume level. At this stage I can not justify my self why I should pay 5 times more for the worse sound quality?
Apart,  I really like the design and presentation. More refined than WA22.
Regards,
Kim


----------



## Fatdoi

kimdeug said:


> *White Noise Test*
> 
> Hello  Cayin HA-6A lovers.
> 
> ...


That's a bit of a bummer isn't it..... so you getting your money back or try another unit?


----------



## Gr3g277

kimdeug said:


> Hello my Friend.
> 
> Really appreciate your efforts to replicate my tests and share your findings.
> At this moment I have canceled order of 6L6 and KT66 tubes, until the hiss issue will be solved.
> ...



Hello kim,

I did your *zero Point* test, *initial noise* test, and *background noise* test, with similiar findings with my high sensitivity headphones.

especially so with the hd650 on high impedance. Background noise is clearly audible, I can hear It as well on quiet moments in acoustic music or classical pieces.




kimdeug said:


> *Results:*  In my situation, adding or removing the power filter and DC blocker from the power chain has not changed the noise coming out from HA-6A. It means no any changes in tonality, loudness, and character of noise - all was the same. The same about Heavy shielded power cables.
> The noise can be described as *combination of Humm and Hiss* in proportion (Humm/Hiss) as 20/80 or 30/70 at Volume position Zero/Minimum*.*
> The noise becomes louder with increasing the Volume.
> The noise was present at all impedances and all outputs.
> ...



I think this is a great resume of the symptoms we are getting with the HA-6A.

That said let's not forget, this is a *very HIGH power* tube amp, and tube amps, especially class A, single ended, low negative feedback are much more noisy than your average SS amp... and making a very silent one is very hard as well.

I think we choose this amp for that reason, the purest amplification form, but it comes with the cost of elevated noise floor.

On the other hand, the selling point of this amp, is the versatility it has, with the loading options, and here it is clearly lacking an acceptable noise floor tu use it with a big majority of todays headphones...

Now It fits perfectly with my arya, but cannot use it properly with with my hd650. 
But my I can also use my aryas on the 8 ohms speaker taps of my primaluna kt88 40w speaker amp with no  noise...
I also tested different rectifier tubes, with no changes, as well as power tubes, with no changes in Initial noise or background noise.
IMO the noise issue is in the preamp section, I can clearly hear changes in noise floor, when swapping preamp tubes. I even had crazy microphonics with some tubes that worked fine in my speaker amp.

I think a mk2 version with maybe a gain switch ? or maybe more steps attenuator ? 

@kimdeug what is the voltage of your unit ? 230 or 110V ? mine is a 230V , I wonder if 110V/60hz versions are quieter ?

@Andykong I would like to apply as well, to any running changes that will be rolled out


----------



## kimdeug

Fatdoi said:


> That's a bit of a bummer isn't it..... so you getting your money back or try another unit?


Not sure yet.

It is 04:30 morning in Auckland now.
Will see at day time.
Actually I really like the built quality and presentation.
Much better, compare to WA22.
But this Hiss/ Humm noise makes this amplifier almost unusable for my headphones collection.
Except AKG 7XX, Q701 (both 62 Ohms, 105 dB),  Fostex T50, 60, Argon (all 50 Ohms 92 dB).
AKG and Fostex are "swallowing" this hiss/humm sound.
Looks like Low Impedance and sensitivity is more beneficial at this case.
What is bother me more that the humming noise does not increase with hissing noise.
While Hissing noise increases linearly with volume increase (but much slower), humm noise is remaining the same and at the end (around 3 o'clock) suddenly becomes more loud and creates distortion.
We will see today, But I really want to fix this issue and keep this amplifier as end game unit.

Regards,
Kim


----------



## kimdeug (Jul 23, 2020)

Gr3g277 said:


> Hello kim,
> 
> I did your *zero Point* test, *initial noise* test, and *background noise* test, with similiar findings with my high sensitivity headphones.
> 
> ...


Waaw, Thank you for reply and following my tests. Highly appreciated. You are real Headphone enthusiast)

I have bought this amp to run  HD800S and ZMF Auteur, mostly for Jazz/blues female vocal listening. Also very like HD6XX for low female vocals. All of this headphones 300 Ohms, Sennheisers 102-103 dB sensitivity and ZMF -97dB
My normal listening Volume actually only 1 step from the minimun/zero Volume and this hissing noise made all my headphones unusable.
My unit is 230V
Interesting finding: that AKG 7XX and Q701 (62 Ohms, 105 dB) are very quiet at medium impedance.
I do not mind to send and wait 2-3 months to fix all issues.

Regards,
Kim


----------



## Gr3g277

Yeah, 

I bought mine mainly for my aryas, but still love my hd650 for vocals, and my kennerton for the fun bass...
I also dropped 2.5K€ on the unit , as an end game amp, and was eyeing on the focal utopia to pair with it, ( we can get good prices used here in france ) but I will wait a bit.

It's a bummer, that noise issue, because it is the best sounding amp that I have ever heard, and the looks is simply awesome.
for the moment I'll use it with my planar, and stick to my asgard3 for the dynamics.

It is really interesting that your AKG's are silent ! cannot understand why really ( maybe the rated sensitivity is overrated ? )

I do not mind waiting for a fix as well.

i'll wait for @Relaxasaurus to receive his unit back, and hope that it will be fixed.


----------



## kimdeug (Jul 23, 2020)

Gr3g277 said:


> Yeah,
> 
> I bought mine mainly for my aryas, but still love my hd650 for vocals, and my kennerton for the fun bass...
> I also dropped 2.5K€ on the unit , as an end game amp, and was eyeing on the focal utopia to pair with it, ( we can get good prices used here in france ) but I will wait a bit.
> ...


Agree, the tube sounds so beautiful and from my experience it is the best match for HD800S and all Sennheiser series.
Apart of pauses between the songs I really immersed in jazz band (listening a lot of acoustic instrumental music too).
But when song is over the hiss is puling me back to reality.
Fostex T50, 60, Argon also sound quieter due to low sensitivity (50 ohms, 92 dB)
I have found interesting feeling that all my planars sound on HA-6A little bit artificially, Like may be lucking some juiciness of the sound, sounds more like hollow sound.
Everything is coming back when I connect all planars to Topping A90, Oppo HA-1 or hybrid Pathos Aurium.

It is quite interesting feeling, that is why planning to use HA-6A mostly with dynamic headphones.


----------



## kimdeug

Andykong said:


> If this is power related background noise, then the determining factor should be impedance and sensitivity of the headphones: you won't hear background noise with high impedance or low sensitivity headphones.  For instance, the headphone amplifier should be silent with 300Ohm HD6xx and HD800S. This doesn't seems to be the case here, so I don't think this is background noise related to high output power.


Hi Andy

I have exactly hiss/humm noise on High impedance from all 1/4. Penta, 4 pin XLR outputs.
Headphones used: Sennh HD800S, HD6XX (300 ohms 103dB),  ZMF Auteur 300 Ohms 97dB
Please response.

Regards,
Kim


----------



## Fatdoi

such a pity i've been on the lookout for OT tube amp for last few years... HA300 came along but has hum/hiss issue.... now HA6a has similar issue....


----------



## kimdeug (Jul 24, 2020)

Fatdoi said:


> such a pity i've been on the lookout for OT tube amp for last few years... HA300 came along but has hum/hiss issue.... now HA6a has similar issue....


Don't worry my friend.
I will fight for it. Have done by myself few mods (Film capacitors, Chokers, matching impedance etc on my Bottleneck Crack Speedball, Have upgraded my LaFigaro 339 too).
I am very serious to keep it for my joy, as the sound produced by HA-6A is amazing, the best ever synergy I have heard with HD800S. And I almost have tried all tube headphone amplifiers available on the market.
From my experience the Humming noise is coming due to luck of isolation/shielding from output transformer, may be something on rectification stage or power filtering. While the hiss is more related to the pre-amplifier stage. Try to contact with Cayin engineers to discuss. I can install a bigger resistor on Balanced output, but I think this solution will only "hide" the existing noise, but not eliminate the problem.
Any idea from electrical point will be very helpful.
Regards,
Kim


----------



## kimdeug (Jul 25, 2020)

Hi All Cayin HA-6A lovers.

Finally, I have *GOOD NEWS!!!!!* to share with you, or at least cheap solution for Hiss solving.
Obviously, it was noticed that low sensitivity headphones Ariya, Fostex T-50, 60 etc with sensitivity 90 dB do much cleaner sound on HA-6A.
Suddenly , I have remembered one video from youtube  Resolve Reviews about Cayin iHA-6.
Where he has mentioned about custom made sensitivity reducer ( 06:45  -on video).

*Link:*_ _

I don't have the XLR one, but I had* iFi iEMatch *adapter for my IEMs around.
So, I have plugged into 1/4 output with HD6XX, and OMG!!!
It was the first time, since I have got HA-6A, when I had 100% satisfaction without any interruption of hiss and humms.
Pure liquid tube magic was flowing to my ears via HD800S and ZMF Auteur too.
Small test has been turned into 3 hours listening session with joy somewhere out of this world.
I think, until Cayin will fix the hiss/humm issue. This is the best and cheapest solution.
Will try to find on web who can make it as Penta, XLR and 1/4 jack and may be will order as permanent accessories specifically dedicated to HA-6A.
I think Cayin should provide these adapters for free to all HA-6A owners witch serial number has been sold before noise fixing upgrade.
If anyone will find this type of adapters, please post link here.


Yes!!!!!, at this stage I will keep my unit until  Relaxasarus and GU1DO will post their feedbacks after repairing.

Regards,
Kim

Photo of iFi iEMatch


----------



## Relaxasaurus (Jul 24, 2020)

kimdeug said:


> Hi All Cayin HA-6A lovers.
> 
> Finally, I have *GOOD NEWS!!!!!* to share with you, or at list cheap solution for Hiss solving.
> Obviously, it was noticed that low sensitivity headphones Ariya, Fostex T-50, 60 etc with sensitivity 90 dB do much cleaner sound on HA-6A.
> ...



This sounds promising, thanks tons for the post! I'm glad you were able to get rid of the hiss but personally I'd rather not deal with an adapter. Hoping the repair is a success but will keep this in my back pocket just in case 👍

Edit- here's the adapter Resolve is talking about at Garage 1217's site:

http://www.garage1217.com/garage1217_diy_tube_headphone_amplifiers_012.htm

$45 USD for the 4-pin XLR balanced version, not bad


----------



## kimdeug (Jul 24, 2020)

oops


----------



## kimdeug (Jul 25, 2020)

Relaxasaurus said:


> This sounds promising, thanks tons for the post! I'm glad you were able to get rid of the hiss but personally I'd rather not deal with an adapter. Hoping the repair is a success but will keep this in my back pocket just in case 👍
> 
> Edit- here's the adapter Resolve is talking about at Garage 1217's site:
> 
> ...



Thank you my half asian brother with the same headphone taste and the same watch ) Yes, I am a full asian headphone enthusiast, if you remember my comment on youtube) "HP Battle! Arya vs LCD-X vs HD800S vs Aeolus"
I am still listening HA-6A non stop with adapter now. And the joy of the sound, I am getting, is absolutely amazing! 
Even, I agree to accept adapters as part of HA-6A equipment.

Big props for adapter link.
Life is much better now.

Regards,
Kim


----------



## iFi audio

kimdeug said:


> I don't have the XLR one, but I had* iFi iEMatch *adapter for my IEMs around.
> So, I have plugged into 1/4 output with HD6XX, and OMG!!! It was the first time, since I have got HA-6A, when I had 100% satisfaction without any interruption of hiss and humms. Pure liquid tube magic was flowing to my ears via HD800S and ZMF Auteur too. Small test has been turned into 3 hours listening joy out of this world.
> I think, until Cayin will fix the hiss/humm issue. This is the best and cheap solution.



Thank you very much, it's always good to know that iEMatch did what it was designed to do


----------



## Relaxasaurus

kimdeug said:


> Thank you my half asian brother with the same headphone taste and the same watch ) Yes, I am a full asian headphone enthusiast, if you remember my comment on youtube)   "HP Battle! Arya vs LCD-X vs HD800S vs Aeolus"
> I am still listening HA-6A non stop with adapter. And the joy of the sound, I am getting now, is absolutely amazing, Even, I agree to accept adapters as part of HA-6A equipment.
> 
> Big props for adapter link.
> ...


Hahaha love it. Brothers forever! I remember your setup from the photo great stuff man!


----------



## kimdeug

Hi Cayin HA-6A lovers

Have found good info how to save a lot of money and make Audio Attenuator DIY
Link: 
https://diyaudioheaven.wordpress.com/headphones/headphone-attenuation-adapter/

Regards,
Kim


----------



## GU1DO

Relaxasaurus said:


> Hahaha love it. Brothers forever! I remember your setup from the photo great stuff man!


Hay any news about your repaired unit ?
mine had a problem in shipping , Cayin used a cheap way of transportation and still after 6 weeks in the way and i still didn't receive mine 
they keep saying its fixed , will see how things go, i would highly advise getting it from a local distributor , international shipping is a nightmare.
tbh i lost any interest in this amp, probably after receiving it i will sell as soon as possible.


----------



## GU1DO

kimdeug said:


> Hi All Cayin HA-6A lovers.
> 
> Finally, I have *GOOD NEWS!!!!!* to share with you, or at least cheap solution for Hiss solving.
> Obviously, it was noticed that low sensitivity headphones Ariya, Fostex T-50, 60 etc with sensitivity 90 dB do much cleaner sound on HA-6A.
> ...



this is not a solution , this thing will degrade sound ,, if you have hiss you should contact Cayin , they revised the design


----------



## GU1DO (Aug 13, 2020)

Andykong said:


> According to @GU1DO,  HA-6A can power HE6se easily  (*HERE*)


Hi ,, is Cayin warranty can be transferred to another person when i sell my HA6A (if i recieve it ) ?


----------



## Zachik

GU1DO said:


> mine had a problem in shipping , Cayin used a cheap way of transportation and still after 6 weeks in the way and i still didn't receive mine
> they keep saying its fixed , will see how things go, i would highly advise getting it from a local distributor , international shipping is a nightmare.


Sorry to hear about your shipping fiasco... In the last few months I have spent a small fortune on international shipping every time I bought something from outside the US!  At least packages arrived quickly. Granted, you have no control on Cayin's shipping choices...



GU1DO said:


> if you have hiss you should contact Cayin , they revised the design


Did they ever admit changing the design?  Any details on WHAT changed?


----------



## kimdeug

GU1DO said:


> this is not a solution , this thing will degrade sound ,, if you have hiss you should contact Cayin , they revised the design


100%  agree that it is not a solution. My unit in repair too. Waiting update from cayin.


----------



## Gr3g277

How did you guys contacted cayin for the repair job ?

I mean did you go to them directly ? or through your local dealer ?

can a local dealer/repairman do the change or does it have to be sent back to the factory in china ?

@Andykong It would be nice to have an official statement on what have been revised and how to take advantage of it.



kimdeug said:


> 100%  agree that it is not a solution. My unit in repair too. Waiting update from cayin.



Yes it is not the perfect solution, but it does the trick for the particular headphones, as a temporary solution. Indeed this resistor network will reduce available power by quite a bit, and will have a fixed output impedance of around 3 ohms, which kinda defeats the purpose of having an impedance matched output switch...

Hell, at that point I think that cayin should make the move and produce the new version internally at the factory, and then make us opt-in for an exchange.... Let's not forget that this is a 2500€ amp.


----------



## kimdeug (Aug 14, 2020)

Gr3g277 said:


> How did you guys contacted cayin for the repair job ?
> 
> I mean did you go to them directly ? or through your local dealer ?
> 
> ...


Yes. I think it is good idea for Cayin, as there are not too many units sold worldwide.
I think it is some flaw in circuit design or faulty parts.

Have contacted to my local dialler and they are directly contacted to Cayin, keeping me in the loop. Also Andykong have replied my PM here and I have linked him into the loop too.

In the past I have done Fitz mod on Darkvoice 336SE installing 2 small capacitors in parallel bypass at cathode for 6SN7 driver to reduce the humm noise. It works very well. Have done the same mod in my Lafigaro 339 for 6SJ7 driver tubes as well. Thinking later to try it for 12AU7 tubes, may be it will work.

But now, waiting any updates from Cayin regarding to repairmen progress. 4 weeks already have passed. Silence.

Kim


----------



## Relaxasaurus

GU1DO said:


> Hay any news about your repaired unit ?
> mine had a problem in shipping , Cayin used a cheap way of transportation and still after 6 weeks in the way and i still didn't receive mine
> they keep saying its fixed , will see how things go, i would highly advise getting it from a local distributor , international shipping is a nightmare.
> tbh i lost any interest in this amp, probably after receiving it i will sell as soon as possible.


I sent mine out for repair on May 29. A lot of lip service but still no sign on when the unit will be shipped back to me. I asked for a refund or even a replacement at this point but have been assured it was actually shipped back to my address. Complete cluster


----------



## GU1DO

Actually i just found that they need my signature on document for inquiry to DHL about the shipment they sent a month ago , (btw when i sent it to them i had to pay premium shipping) and now it look like it is lost , they don't want to admit it and make me wait until it pass 30 days from the last tracking update which means till the 18th of August , so i guess i have to wait extra few days before the next action , 

I requested a refund but they refused  and they offered a discount on future purchase. What..... ,* if the shipment is lost i hope they accept the refund because really i don't care about this amp any more though i already spent 250$ on tubes.*

Here is few details about the shipment tracking 
They sent it at 2020-07-06 and the last update on the Tracking# is at 2020-07-18 so i should wait till 18th of august 

*I wished Cayin match Audio-Gd service which cover shipping both ways the first year and the warranty is 10 years , but what to say *


----------



## GU1DO (Aug 14, 2020)

Zachik said:


> Sorry to hear about your shipping fiasco... In the last few months I have spent a small fortune on international shipping every time I bought something from outside the US!  At least packages arrived quickly. Granted, you have no control on Cayin's shipping choices...
> 
> 
> Did they ever admit changing the design?  Any details on WHAT changed?


Actually when i bought the amp from Cayin they charged me 300$ for shipping so it arrived in a really good time but i paid for that shipping
when i shipped it to them for repair i paid around 350$
so 650$ just for shipping cost on my expanse ,,
Now i expected the same level BUT ???

About the changing in the design i dont know what they did but they said in the email when i asked :


> We will follow your instruction and let the German repair center sent out the unit. Once tracking number is available we will let you know.
> 
> Amplifier will be packed carefully and no scratches on the amplifier. *Concerning the amplifier it has been updated to our latest state that noise issue has been solved*. All condition are the same as the new ones out of our factory for the schematics. Please kindly note.
> 
> ...


----------



## kimdeug

GU1DO said:


> Actually i just found that they need my signature on document for inquiry to DHL about the shipment they sent a month ago , (btw when i sent it to them i had to pay premium shipping) and now it look like it is lost , they don't want to admit it and make me wait until it pass 30 days from the last tracking update which means till the 18th of August , so i guess i have to wait extra few days before the next action ,
> 
> I requested a refund but they refused  and they offered a discount on future purchase. What..... ,* if the shipment is lost i hope they accept the refund because really i don't care about this amp any more though i already spent 250$ on tubes.*
> 
> ...


Sorry to hear the trouble you are going through. Seems like it is bad luck. Any way if the shipment is lost it should be fully refunded by the sending side.
In my situation the same: I have already spent 1500$ for tubes (GEC KT88 and Markoni KT 88 -Total 4 tubes) few 12AU7 tubes and don't have amplifier on hand.
But will not give up as from my 10 years search for end game headphone amplifier it is the best sounding unit I had. (Second will be Felix Euforia - IMHO the best match for Focal headphones). But for Sennheiser series  - Cayin HA-6A is my end game choice. WA22 is not bad, but too old in design. WA33 is above my budget.
So, I agree to go through all this trouble if the result at the end will be pure sound of KT88 without any hiss/humm.

Regards,
Kim


----------



## GU1DO

kimdeug said:


> Sorry to hear the trouble you are going through. Seems like it is bad luck. Any way if the shipment is lost it should be fully refunded by the sending side.
> In my situation the same: I have already spent 1500$ for tubes (GEC KT88 and Markoni KT 88 -Total 4 tubes) few 12AU7 tubes and don't have amplifier on hand.
> But will not give up as from my 10 years search for end game headphone amplifier it is the best sounding unit I had. (Second will be Felix Euforia - IMHO the best match for Focal headphones). But for Sennheiser series  - Cayin HA-6A is my end game choice. WA22 is not bad, but too old in design. WA33 is above my budget.
> So, I agree to go through all this trouble if the result at the end will be pure sound of KT88 without any hiss/humm.
> ...


I dont know about the sound , i wasnt impressed when i got it , but tbh i didnt roll tubes or did a full burn in so its not fair to say it because i didnt use it enough.


----------



## kimdeug (Aug 14, 2020)

GU1DO said:


> I dont know about the sound , i wasnt impressed when i got it , but tbh i didnt roll tubes or did a full burn in so its not fair to say it because i didnt use it enough.


Sure, you will change your opinion later. And may be waiting time and all this extra expenses will be paid off at the end. I am a very passion about headphones hobby and even crazy enough to fly US and Singapore just for CanJam from New Zealand. Up to this day I can not see any alternatives to HA-6A, so really hope they will fix the hiss/humm issues, while in your situation it looks like more logistic or DHL delivery issues. Finger cross it will not affect the quality of sound. Please, let us know about your situation.
Because of Corona I was expecting 2-3 months without amplifier. 
Regards, Kim


----------



## Gr3g277

well, based on you guys experience, I think I will wait for you to receive the "repaired" unit... And see what it is all about.

I am still enjoying mine very much with my aryas, and using my asgard3 for the other headphones.


----------



## Relaxasaurus

Gr3g277 said:


> well, based on you guys experience, I think I will wait for you to receive the "repaired" unit... And see what it is all about.
> 
> I am still enjoying mine very much with my aryas, and using my asgard3 for the other headphones.


Smart move imo


----------



## Zachik

kimdeug said:


> looks like more logistic or DHL delivery issues





kimdeug said:


> Because of Corona I was expecting 2-3 months without amplifier.


I got a DHL package yesterday, that was shipped from Europe to the US approx. 10 days ago. In fact, took 1 day from arriving to the US (east coast) until I got it (in the west coast).
No reason or excuse for DHL to take 2+ months!


----------



## GU1DO (Aug 14, 2020)

> @Andykong It would be nice to have an official statement on what have been revised and how to take advantage of it.
> Hell, at that point I think that cayin should make the move and produce the new version internally at the factory, and then make us opt-in for an exchange.... Let's not forget that this is a 2500€ amp.


you know the HA6A is sold for 2000$ new from the factroy in the Chinese websites ?


----------



## Articnoise

I must admit that am surprised to read how badly Cayin, an ones respectable company, seems to have handled this.


----------



## GU1DO




----------



## GU1DO

Now i pray they never find my amp ,, i really need the refund to look for another amp , selling it with that hiss will be very hard ...grrrrr


----------



## GU1DO

Articnoise said:


> I must admit that am surprised to read how badly Cayin, an ones respectable company, seems to have handled this.


till now my experiance with Cayin is totally bad, i wish it was other way around , that amp had real potential.


----------



## Relaxasaurus

Big bummer for sure. There's still a chance your repair company in Germany actually did proper work and testing before shipping it back. But yea, that's the only glimmer of hope I can offer.

I bought the $45 attenuator and will report back the results.


----------



## GU1DO

Relaxasaurus said:


> Big bummer for sure. There's still a chance your repair company in Germany actually did proper work and testing before shipping it back. But yea, that's the only glimmer of hope I can offer.
> 
> I bought the $45 attenuator and will report back the results.


i already spent 3000$ on this amp so i am not expecting a hiss with it and fix it with an attenuator that i know it will degrade sound , 
i tried things like that in the past they never sound good , they muffle the sound and sure you will loose transparency.

btw i liked the snake, nice touch hehehe


----------



## kimdeug

Hello Cayin HA-6A lovers.

I f you follow this thread you know that I have humm/ hiss issue with my HA-6A.

The noise can be described as *3 different noises AT THE SAME TIME!!!!: *

Headphones used: Sennheiser HD800S, HD6XX, HD600, HD650, ZMF Auteur, Focal Utopia, Focal Elex

1. *Humm noise*. At Zerro Volume - around 20dB loud and 50-60HZ tonality.
2. *Hiss noise*. Sounds like: " Th_Th_Th_Th" . Also at Zerro Volume around 20dB loud. 
It has been found that increasing the Volume only increases the Hiss noise, while the Humm noise remains the same around 20dB at all Volume positions.
3. *Distortion noise*. Sounds like: "R_R_R_R_R", when the Volume at 1 o'clock at RCA input, 3 o'clock at XLR input and last few Volume steps (24-25) at no any input connections to Cayin HA-6A.

The humming noise does not increase with hissing noise.
While* Hissing noise *increases linearly with Volume Up (but much slower), *Humm noise* remains at the same level, and only with Volume around 3 o'clock, suddenly becomes more loud and creates distortion.

My unit still in repair, but I have found some helpful link to understand the source of noise.
Hope it will help to trace down the humm noise.

Regards,
Kim
Link:


----------



## Andykong

Relaxasaurus said:


> Big bummer for sure. There's still a chance your repair company in Germany actually did proper work and testing before shipping it back. But yea, that's the only glimmer of hope I can offer.
> 
> I bought the $45 attenuator and will report back the results.



I can feel your discontent, I'll be in your same boat if I were encountered the same problem. 

We need to collect the machine and inspect again thoroughly in order to determine whether its the repair problem or there is hidden problem that we didn't aware.  Please contact your dealer to arrange refund and return the HA-6A, we'll work with MusicTeck to collect the machine from them. 

Sincerely apologize for all the inconvenience caused, we'll study your HA-6A in detail when we it return to our factory.


----------



## kimdeug

Andykong said:


> I can feel your discontent, I'll be in your same boat if I were encountered the same problem.
> 
> We need to collect the machine and inspect again thoroughly in order to determine whether its the repair problem or there is hidden problem that we didn't aware.  Please contact your dealer to arrange refund and return the HA-6A, we'll work with MusicTeck to collect the machine from them.
> 
> Sincerely apologize for all the inconvenience caused, we'll study your HA-6A in detail when we it return to our factory.


What about units from Germany, New Zealand and France?


----------



## GU1DO

Andykong said:


> I can feel your discontent, I'll be in your same boat if I were encountered the same problem.
> 
> We need to collect the machine and inspect again thoroughly in order to determine whether its the repair problem or there is hidden problem that we didn't aware.  Please contact your dealer to arrange refund and return the HA-6A, we'll work with MusicTeck to collect the machine from them.
> 
> Sincerely apologize for all the inconvenience caused, we'll study your HA-6A in detail when we it return to our factory.


I would appreciate if you contact John from Cayin to consider a refund for me also, the amp now should be returning to Germany (to the repair center),  *and they will ship it again to me* ,, i dont want to find it still has a problem and spend another 350$ to ship it back, i can provide the tracking# they gave me and you can check yourself the status of the shipment, i can wait for them to decide if it lost , or when they recieve it , but please dont send anything back to me ,, just refund.


----------



## Andykong

@GU1DO @kimdeug 

Sorry for the problem you have encountered with our HA-6A.  If the repair turns out to be unsuccessful, you can also contact your seller or agent and ask for refund.   We hope you can grant us this opportunity to at least give it a try to solve the problem.


----------



## Gr3g277

Andykong said:


> @GU1DO @kimdeug
> 
> Sorry for the problem you have encountered with our HA-6A.  If the repair turns out to be unsuccessful, you can also contact your seller or agent and ask for refund.   We hope you can grant us this opportunity to at least give it a try to solve the problem.



Hi andykong !

Please do not forget me 

Do you think it would be possible to have details on what the fix is ?


----------



## kimdeug (Aug 18, 2020)

Gr3g277 said:


> Hi andykong !
> 
> Please do not forget me
> 
> Do you think it would be possible to have details on what the fix is ?


Thats why I have asked my friend: one for you in France, one for me in New Zealand and one for GI1DO in Germany.
Relaxasaurus has already contacted in NY. Only three of us left. But I wanna fixed amp instead of refund, as I really like it.
Regards, Kim


----------



## Relaxasaurus

kimdeug said:


> But I wanna fixed amp instead of refund, as I really like it.


Same page as you.


----------



## GU1DO

Andykong said:


> @GU1DO @kimdeug
> 
> Sorry for the problem you have encountered with our HA-6A.  If the repair turns out to be unsuccessful, you can also contact your seller or agent and ask for refund.   We hope you can grant us this opportunity to at least give it a try to solve the problem.


I bought it directly from Cayin


----------



## Andykong

Gr3g277 said:


> Hi andykong !
> 
> Please do not forget me
> 
> Do you think it would be possible to have details on what the fix is ?



I tried to, that's why I want to wait till I receive the report from New Zealand dealer initially.


----------



## Andykong (Aug 18, 2020)

kimdeug said:


> Yes I have hiss too.It is more like combination of Hiss and Humm together. In proportion Hiss/Humm as 70/30. Hiss is gradually increases with increase of Volume, but much slower (not like sound increases), while the Humm noise almost reminds on the same level and with Volume increase, suddenly start to distort (depends of RCA or XLR input selected) at 1 or 3 o'clock respectively.  Right now I am using Sennheiser HD800S. Hiss/Humm on 4 pin XLR output in all L, M, H impedance positions. Hiss/humm starts to distorted when Volume at 3 o'clock (assuming that the Volume knob traveling from min 7 o'clock to max 5 o'clock position). I am using XLR input from DAC with max volume for me no more than at 9 o'clock position).
> In my situation hiss/humm comes from all 1/4, pentagone, and 4pin XLR outputs. Looks like loud valves, but very noticeable when switching between headphone's outputs  on minimal volume.
> Control test: Unplug everything. No any inputs. Only Power cable. Sennheiser HD800S plugged in into 4 pin XLR output. Hiss starts on the last 2-3 actuators steps on each L,M, H impedances.
> Next test: RCA input from DAC. Music on pause. Hiss starts from 1 o'clock volume position, very loud on maximum volume on each L, M, H impedances.
> ...



kimdeug PMed me and asked me to take on his case starting from page 15.  I did, but I was hoping that I can receive the report from New Zealand dealer and find out what happened to kimdeug’s HA-6A before I explain his situation. Unfortunately there wasn’t any update till now, so I'll try to clarify some questions first and come back to that later.

Regarding the noise test that kimdeug has conducted, some of them are truly valid, otherwise I won't wait for the inspection report from his dealer.  However, tube amplifier has a very different electrical characteristic from solid state amplifier, so some of the test that is applicable to Solid-State but not to tube amplifier. One of the biggest different is that you must not listen to the tube amplifier with unconnected input. I described this as “Open-loop” condition.  This is very similar to the condition that @dpump has explained in *#211*.  Alternatively when you connected a DAC or CD player as your music source to the tube amplifier properly, you are listening to your amplifier in Closed-loop condition. I have mentioned, previously in other Cayin tube amplifier thread that you’ll hear excessive noise when you hear the amplifier at open loop condition. I know this sound crazy because we always assume that when we didn’t connect anything to the amplifier, we’ll reduce interference from other equipment and listen to the amplifier only, but the input impedance of tube amplifier makes it a totally different story.

External interference in open-loop condition applied to both Solid State and Vacuum tube amplifier, but the components of Solid State amplifier will typically make the input impedance at fairly low rating, something between several KΩ to 10KΩ, and the low input impedance makes them almost immune to interference. On the other hands, the input impedance of tube amplifier will raise to 40~100+ KΩ. The high input impedance will amplify the interference and spoiled your test. Theoretically, if we determined, we can lower the input impedance to a much lower value (but still higher than the input impedance of Solid State amplifier) but that will compress the dynamic and music will lost its liveliness.

So what was the hissing noise from interference related to volume control setting? That’s because the each volume control position of HA-6A has its own resistor, and the value of resistor are part of the sound turning process. So as you turn up the volume control, the input impedance will increase.  It doesn't increase linearly but last few steps in the volume control have the biggest change.  For the record, at maximum volume the input impedance raise all the way to 100KΩ.  Therefore at certain volume position, the high impedance will make the external interference audible, and that’s why some volume position is higher then other and the impedance of your headphone will contribute to that as well.

That explained why you won’t hear any noise with Solid State amp in open-loop condition but you hear relatively loud noise with tube amp in open-loop condition and the noise varied according to volume position and headphone loading. Even in closed-loop condition, interference can still enter the system, but at a much lower level. Interconnect with good shielding will help to reduce the interference from entering your audio system through.

Last but not least, because of the nature of amplification in tube amplifier, tube amplifier are more prone to RF interference and ground noise, and the overall noise floor is indeed higher then solid state amplifier, especially high power headphone amplifier that can drive the most demanding headphones such as HE6, Susvara and AB1266.  Our concern is to control the  noise to the level that it won't get into your way when you listen to music practically.  However, if you turn off the music and deliberately "look for" noise, you'll find it very easily.  This is like deliberately reduce the signal to noise ratio of your amplifier in order to make the noise audible.  This reminded us a case that an oversee customer complained he can hear hum noise from the output transformers of his Cayin speaker amplifier.  We tested his unit again and we found it clean and meeting our standard, after a lengthy communication, we found out that he use a pair of stethoscope to test whether the transformer is silent.

I am not trying to falsify kimdeug's test,  I want to find out whether there is anything wrong with his HA-6A, and that implies I suspect something is not right with his unit, but I hope we can appreciate the musicality and the constraints of high power tube headphone amp at the same time.


----------



## GU1DO

Now i am in the hunt for the amp LOL
Cayin accepted to refund me once they have the amp which look like it is lost by now. they asked me to ship it once i have it hehehe , wtfff they should look for the shipment not me but i will try my best to find it ,, pray for me guys
Fingers crossed


----------



## GU1DO

Andykong said:


> kimdeug PMed me and asked me to take on his case starting from page 15.  I did, but I was hoping that I can receive the report from New Zealand dealer and find out what happened to kimdeug’s HA-6A before I explain his situation. Unfortunately there wasn’t any update till now, so I'll try to clarify some questions first and come back to that later.
> 
> Regarding the noise test that kimdeug has conducted, some of them are truly valid, otherwise I won't wait for the inspection report from his dealer.  However, tube amplifier has a very different electrical characteristic from solid state amplifier, so some of the test that is applicable to Solid-State but not to tube amplifier. One of the biggest different is that you must not listen to the tube amplifier with unconnected input. I described this as “Open-loop” condition.  This is very similar to the condition that @dpump has explained in *#211*.  Alternatively when you connected a DAC or CD player as your music source to the tube amplifier properly, you are listening to your amplifier in Closed-loop condition. I have mentioned, previously in other Cayin tube amplifier thread that you’ll hear excessive noise when you hear the amplifier at open loop condition. I know this sound crazy because we always assume that when we didn’t connect anything to the amplifier, we’ll reduce interference from other equipment and listen to the amplifier only, but the input impedance of tube amplifier makes it a totally different story.
> 
> ...


i didnt read the whole post because i dont understand technical things , but for the record ,my Bottlehead Crack amp which is a home mad amp , doesnt hiss


----------



## Slim1970

GU1DO said:


> Now i am in the hunt for the amp LOL
> Cayin accepted to refund me once they have the amp which look like it is lost by now. they asked me to ship it once i have it hehehe , wtfff they should look for the shipment not me but i will try my best to find it ,, pray for me guys
> Fingers crossed


This is bad, I really had high hopes for this amp. It has all the features you needed to be a potential endgame all in one amp solution. I wish you luck


----------



## kimdeug (Aug 21, 2020)

Andykong said:


> kimdeug PMed me and asked me to take on his case starting from page 15.  I did, but I was hoping that I can receive the report from New Zealand dealer and find out what happened to kimdeug’s HA-6A before I explain his situation. Unfortunately there wasn’t any update till now, so I'll try to clarify some questions first and come back to that later.
> 
> Regarding the noise test that kimdeug has conducted, some of them are truly valid, otherwise I won't wait for the inspection report from his dealer.  However, tube amplifier has a very different electrical characteristic from solid state amplifier, so some of the test that is applicable to Solid-State but not to tube amplifier. One of the biggest different is that you must not listen to the tube amplifier with unconnected input. I described this as “Open-loop” condition.  This is very similar to the condition that @dpump has explained in *#211*.  Alternatively when you connected a DAC or CD player as your music source to the tube amplifier properly, you are listening to your amplifier in Closed-loop condition. I have mentioned, previously in other Cayin tube amplifier thread that you’ll hear excessive noise when you hear the amplifier at open loop condition. I know this sound crazy because we always assume that when we didn’t connect anything to the amplifier, we’ll reduce interference from other equipment and listen to the amplifier only, but the input impedance of tube amplifier makes it a totally different story.
> 
> ...


Hi Andykong

Thank you for reply and clarifications.
Regarding to my tests: Of cause, I have conducted the same tests with all my DAC sources (look my DACs). And you will not like the results. Because, the Humm/hiss noise was on close loop too. The quietest  result was at no any sources plugged to HA-6A - around 20dB at Zerro Volume,  around 25dB with XLR input and 30dB at RCA input. So, I have published the results with the minimal noise scenario with no source plugged. Was used hi-End triple shielded XLR and RCA cables.

From my research I prone to think that the humm noise (non volume dependent) produced due to alternative current 60Hz still comes to the driver 12AU7 tube.

*HUMM* noise can be due to:

not enough shielding, and as result secondary EM inductance in the circuit.
loose ground tightening
Power filtering (the capacitors are not smoothing the rips enough)

What usually using to find hum issues is a tape head Demagnetizer. A Demagnetizer uses an electromagnet to produce an AC field around its probe tip. I'd use a scope to monitor the background noise then probe around the circuitry wiring to find wires and/or components that are most susceptible to hum and then move them around, usually closer to the chassis to minimize the amount of noise they can generate.


Common sources of *HISS *noise are cathode biasing resistors, coupling capacitors (between gain stages) or reverb/trem. cct.'s. After eliminating the obvious (tubes, AC power source, etc.), depends of the guilty of internal component(s).
Some amps hiss brand new (by design) and some develop hiss over time (as components like carbon composite resistors deteriorate). Sometimes, due to using some noisy carbon-film or carbon-comp instead of metal-film resistors in the amp. Could have some non-polarized caps wired backwards (yes that CAN make a difference especially with Orange Drops) or low-quality/wrong type of coupling caps. There are quite a few design issues in an amp that contribute to noise. If several of these reasons are built into the amp, then they multiply quickly and the amp gets noisy.

Hiss noise could be due to:

noisy tubes
Noisy plate resistors. The carbon composition resistors used on the plates of preamp tubes often go very noisy, especially in older Fenders. If swapping tubes does not fix the trouble, locate the circuit that seems noisiest by tube swapping, and then replace the plate resistors in that circuit with equal-value metal film or metal oxide resistors. You can use carbon comp if you can find them, but the problem is likely to recur.
Noisy resistors in the B+ decoupling string, often around 10K in value
Unusual: An ultrasonic oscillation can cause an intense insect-like hissing that sounds very much unlike normal hiss.
Rare: leaky coupling capacitors or faulty controls
Rare: a slight ongoing arc on the output tube socket(s)
Rare: a bad solder joint somewhere in the signal chain
Rare: internal arcing or noise in almost any part in the preamp section
A good way to divide and conquer is to turn the volume control(s). If the hiss changes levels as you do this, then the source of the hiss is something that affects the stages of the amp before the volume control (this is a note regarding to your (Andykong) comment about resistor step Volume attenuator above). A faulty, hissing preamp tube will be turned up this way very quickly. Conversely, if the volume control does not affect the hiss, the cause is somewhere after the volume control. In general, the volume level of the hiss is an indicator of where the hiss is occurring - the louder the hiss, the more likely its source is near the input of the amp where the gain applied to it will be the greatest

The procedure of locating by removing one tube at at time working from the phase inverter/driver back towards the input until removing a tube no longer stops the hiss should then localise the problem to one tube's worth of circuitry.


For hiss better to monitor the noise levels with a scope and try different tubes to find ones that produced minimal background noise. You can do the same for resistors and caps in key areas like coupling caps and bias resistors if needed. All this can be time consuming but it is what's needed sometimes when an amp misbehaves. Small tweaks that cant be heard clearly with the ears are cumulative so finding several may help to improve things.

This is my small extract from research finding.
Also suggest to look Fitz mod on Darkvoice thread, which helps me a lot to reduce humm on driver tube.
Hope it will help to bring HA-6A back to desired amplifier.

Regards, Kim


----------



## IPMano

Hi all,
I'm glad I didn't buy the HA-6A, I'm very happy with my Feliks Euforia which doesn't make any noise, hiss, etc ... just music. My Cayin HA-1A MKII had a faulty power tube, but it still does a little zzzz which changes depending on the position of the impedance selector, I think I will sell it soon.


----------



## Gr3g277

Hi guys,

Yes all the testing I did was in a close loop condition ( with dac connected to input with xlr or RCA ).
I think we all understand that making a powerful AND quiet tube headphone amp is no easy task.... and that tube amps do not respond the same way as solid state amps, for power delivery, or noise levels.

In my opinion, there is an easy fix, reduce the gain of the amp. We already know that it works ,because the IEM adapter @kimdeug tried worked to reduce the noise level of the amp.
The problem is that it is a resistor network attached to output transformers, the amp sees a 30 something Ohm load, and the headphone sees a 3 something ohm output resistance.the result is a reduction of Gain of 10db ( or more depending on the maths done, when calculating the resistors values ). And you lose the benefit of impedance matching , and maybe ,compressed dynamics. ( Should be ok if the amp is left with L impedance mode though, I wonder ).

So the easy fix should be adding a simple -10db "Low Gain" switch, on the preamp side of the amplifier, instead of on the output.
That would make the amp usable with high sensitivity headphones, balanced or not. reduce the preamp sensitivity to noise, microphonics etc...

When you need all the horsepower, just flip it to "normal" mode, and boom here you can go deaf with your susvara's, as it was designed. ( Still not going past 12 o'clock with my aryas XD )

When using utopia's or anything more than 100db sensitive , use Low gain mode.

Hell, my 200€ Schiit asgard3 has exactly that.... and sounds good in both mode with no noise to heard.

that is just my two cents.

Now I will do my homework, so I can keep up with @kimdeug great technical ideas.


----------



## Fatdoi

IPMano said:


> Hi all,
> I'm glad I didn't buy the HA-6A, I'm very happy with my Feliks Euforia which doesn't make any noise, hiss, etc ... just music. My Cayin HA-1A MKII had a faulty power tube, but it still does a little zzzz which changes depending on the position of the impedance selector, I think I will sell it soon.


oh well I'm not so glad that I'm still hunting for a OT tube amp... still resisting on Woo stuffs and so far Cayin has not shown they upped the game since their HA300 issue.... to invest such money for a product that seems they haven't done their beta testing is kinda disappointing.... and to use their initial customers as their testing subjects is very cruel to say the least...


----------



## IPMano

Fatdoi said:


> oh well I'm not so glad that I'm still hunting for a OT tube amp... still resisting on Woo stuffs and so far Cayin has not shown they upped the game since their HA300 issue.... to invest such money for a product that seems they haven't done their beta testing is kinda disappointing.... and to use their initial customers as their testing subjects is very cruel to say the least...


are you looking for an OTL amp? I recommend the feliks euforia.


----------



## kimdeug (Aug 21, 2020)

IPMano said:


> are you looking for an OTL amp? I recommend the feliks euforia.


Congrats, 
Feliks Euforia is very solid choice, Especially, the best pairing with Focal's headphones. Again, for my preference I am a Sennheiser sound person and the best OTL combination was for me is Cayin HA-6A.  Apart of all troubles with hiss/humm noise it still sounds very good.
Few things are frustrating me: as the Cayin decided to use the customers as first production test trials, and try to use the dealers service centers all around the world to fix their problem, instead of call out all units (4 of them worldwide) to their facilities in China and do proper investigation. ( I think Cayin can afford to pay shipment of 4 units back to the factory on own expenses (Not like GU1DO who has spent on shipment around 1/3 of the price because of that faults).
The local service centers are not interested to do proper repair or deep investigation as they are not paid for production design and not involved in Cayin business.
That's my thought now.
Regards,
Kim


----------



## Fatdoi

IPMano said:


> are you looking for an OTL amp? I recommend the feliks euforia.


No I'm looking for amp with output transformer.... for OTL there're 100s choices, don't want to touch them.


----------



## OctavianH

Fatdoi said:


> No I'm looking for amp with output transformer.... for OTL there're 100s choices, don't want to touch them.



I know that Woo Audio have some SET designs. May I ask why do you want an output transfomer?


----------



## Fatdoi

OctavianH said:


> I know that Woo Audio have some SET designs. May I ask why do you want an output transfomer?


I'm quite weary the protection between the full power of the tubes to the headphones are only some caps/transistors..... any of them fail, it'll either fry my headphones or my eardrums which i'm not looking forward to any..... however if a transformer fails, the sound fades with it......


----------



## OctavianH

Well, using OTLs for some years already and never got a problem...


----------



## wazzupi

Fatdoi said:


> oh well I'm not so glad that I'm still hunting for a OT tube amp... still resisting on Woo stuffs and so far Cayin has not shown they upped the game since their HA300 issue.... to invest such money for a product that seems they haven't done their beta testing is kinda disappointing.... and to use their initial customers as their testing subjects is very cruel to say the least...


my Cayin ha-300 is flawless, I think it's 50/50, people laying blame to a company(because they dont know how to fix a power source issue) and the other actually having issues with the amp.


----------



## Zachik

Fatdoi said:


> I'm quite weary the protection between the full power of the tubes to the headphones are only some caps/transistors..... any of them fail, it'll either fry my headphones or my eardrums which i'm not looking forward to any..... however if a transformer fails, the sound fades with it......


Woo WA6 is a solid choice for $699 with free shipping! (for that price range, you cannot beat it IMHO)
I have a 1st gen unit, and it sounds very clean and no hiss or hum at all.


----------



## Zachik

wazzupi said:


> my Cayin ha-300 is flawless, I think it's 50/50, people laying blame to a company(because they dont know how to fix a power source issue) and the other actually having issues with the amp.


A friend of mine got one of those, and I did audition it when he got it new around beginning of 2020 or end of 2019 (after burn-in period).
No idea about 50/50 you mention, but at least my friend's unit is very quiet and great sounding!
Frankly, if I had space in my over-loaded rack - I would buy one of these. I *really *liked it


----------



## wazzupi

Zachik said:


> A friend of mine got one of those, and I did audition it when he got it new around beginning of 2020 or end of 2019 (after burn-in period).
> No idea about 50/50 you mention, but at least my friend's unit is very quiet and great sounding!
> Frankly, if I had space in my over-loaded rack - I would buy one of these. I *really *liked it


Has he done any tube rolling, I'm interested in finding some new tubes to play around with , I've got some melz 1963 6n8s(apparently the best version) durmont 22de4s and tung sols plus the OG tubes. I enjoy the stock tubes, melz make magic out of the mids !!


----------



## Zachik

wazzupi said:


> Has he done any tube rolling, I'm interested in finding some new tubes to play around with , I've got some melz 1963 6n8s(apparently the best version) durmont 22de4s and tung sols plus the OG tubes. I enjoy the stock tubes, melz make magic out of the mids !!


From memory, he rolled the rectifier tubes which were VERY cheap. He did NOT roll the 300B tubes (yet). Those get VERY expensive, fast!
So, even with the stock Chinese 300B tubes - this amp was very impressive


----------



## OctavianH

Zachik said:


> Woo WA6 is a solid choice for $699 with free shipping! (for that price range, you cannot beat it IMHO)
> I have a 1st gen unit, and it sounds very clean and no hiss or hum at all.



It depends what headphones you use. I know someone who sold WA6 to buy an Elise because he was not pleased about how T1 600Ohm was amplified on WA6.


----------



## Gr3g277

hey guys,

I came accross this, by looking for stuff online, does anyne have an experience with those ?

http://www.rothwellaudioproducts.co.uk/html/attenuators.html

Those are inline attenuators, that reduces the gain and sensitivity of the next device in the chain. Could be worth giving it a try ?

What do you think ?


----------



## Relaxasaurus

Gr3g277 said:


> hey guys,
> 
> I came accross this, by looking for stuff online, does anyne have an experience with those ?
> 
> ...


I tried the Garage1217 attenuator and @GU1DO was right, it did affect sound quality.

It looks like these can connect between your DAC and the amp though so it does pique my interest, nice find. If they were on Amazon I'd buy and try, not willing to pay for intl shipping on another potential fix right now.


----------



## Gr3g277

Relaxasaurus said:


> I tried the Garage1217 attenuator and @GU1DO was right, it did affect sound quality.
> 
> It looks like these can connect between your DAC and the amp though so it does pique my interest, nice find. If they were on Amazon I'd buy and try, not willing to pay for intl shipping on another potential fix right now.



Yes that piqued my attention, I think I'll give a shot on those
https://www.amazon.fr/stageline-rég...rca&qid=1598280355&sprefix=attenuateur&sr=8-1

30e on french amazon with selectable gain attenuation.
Maybe not as good quality as the ones from rothwell.
Not sure it will work though, as i believe,reducing
Volume on the dac does not reduce the noise coming from the amp right ?


----------



## Relaxasaurus (Aug 24, 2020)

Gr3g277 said:


> Not sure it will work though, as i believe,reducing
> Volume on the dac does not reduce the noise coming from the amp right ?


That's what I'm thinking, especially since the hiss is still very apparent when no source is plugged in at all.

One thing that was pointed out to me is if you remove the 12au7 input tubes and run the amp the headphones are dead silent.

Granted, no audio can play either (hah!) but I was told to try other input tubes that are of higher quality and really low noise. Not sure what that would be but there's another lead if you have some lying around.


----------



## Gr3g277

Relaxasaurus said:


> That's what I'm thinking, especially since the hiss is still very apparent when no source is plugged in at all.
> 
> One thing that was pointed out to me is if you remove the 12au7 input tubes and run the amp the headphones are dead silent.
> 
> Granted, no audio can play either (hah!) but I was told to try other input tubes that are of higher quality and really low noise. Not sure what that would be but there's another lead if you have some lying around.



Too bad the 12au7 is not really interchangeable with other tubes from the 12xx7 family. Operating points are too different. from all the 12au7 i have the best are the stock ones and the sylvania 6189, all the other i have are much more noisy !!

Actually a close tube would be the 6sn7, but it will need an adapter. And they have twice the heater current draw, which the power supply will have to provide... So not for use with kt88 power tubes

I Was also looking at stuff like faraday cages for the input tubes, or tube dampers, socket savers with isolation base....not sure that is not just snake oil...

On another not, ignoring the hiss, i plugged in my hd650 in SE high impedance, and boy oh boy does this amp makes them sing !!!
I forgot how good , rich and creamy midrange those cans could give me....

I really want to try an utopia with it, just to hear what the cayin can do with it


----------



## Relaxasaurus

Gr3g277 said:


> On another not, ignoring the hiss, i plugged in my hd650 in SE high impedance, and boy oh boy does this amp makes them sing !!!
> I forgot how good , rich and creamy midrange those cans could give me....
> 
> I really want to try an utopia with it, just to hear what the cayin can do with it


Dude, I just completed my review vs the WA22 and although the local Cayin distributor offered me a full refund I couldn't send it back! If they ever fully fix the hiss at higher impedance settings then I may go through some sort of recall process but as for now she's staying with me. It is really that good 😁👍


----------



## Gr3g277

Relaxasaurus said:


> Dude, I just completed my review vs the WA22 and although the local Cayin distributor offered me a full refund I couldn't send it back! If they ever fully fix the hiss at higher impedance settings then I may go through some sort of recall process but as for now she's staying with me. It is really that good 😁👍



Yeah it is really good !! Man I subscribed to your channel, waiting for that video to drop !

Also I wonder how the heddphone sounds with the ha 6a, do you still have it around ?


----------



## Relaxasaurus

Gr3g277 said:


> Also I wonder how the heddphone sounds with the ha 6a, do you still have it around ?


I don't have it, they belonged to my buddy but I'll see if he can bring them over.

Have Meze Empyreans en route!


----------



## Gr3g277

Relaxasaurus said:


> I don't have it, they belonged to my buddy but I'll see if he can bring them over.
> 
> Have Meze Empyreans en route!


Sounds like a arya vs heddphone vs empyreans! 
;-p
I m lurking over a used utopia... or a kennerthon thekk .
But those are high sensitivity... not sure it isnthe right move atm lol


----------



## Bonesy Jonesy

Just been reading all the posts on this forum for past hour and 95% are regarding this hissing problem ! 

CAYIN YOU SHOULD BE ASHAMED OF YOURSELF ON HOW YOU HAVE TREATED YOUR CUSTOMERS ON THIS FORUM....SHAME ON YOU !


----------



## JazzVinyl

kimdeug said:


> *Humm noise* remains at the same level, and only with Volume around 3 o'clock, suddenly becomes more loud and creates distortion.



50/60hz tube hum often comes from the AC that sent to the tube heaters.  One thing Cayin repairmen should try, is heating the tube with very pure (well regulated and grounded) DC current.  To see if that eliminates the HUM portion of this problem.


----------



## Gr3g277

JazzVinyl said:


> 50/60hz tube hum often comes from the AC that sent to the tube heaters.  One thing Cayin repairmen should try, is heating the tube with very pure (well regulated and grounded) DC current.  To see if that eliminates the HUM portion of this problem.



The tube heaters are already fed by DC, coming from the two 22DE4 half-wave rectifiers.
don't really know why they chose this reference ( hard to find replacements or equivalents ) instead of more commonly available full-wave 5U4G or 5AR4.
hum is not really an issue, only hiss ( noise floor of the amp) a little hum occurs at 3-4pm on the dial on the 300ohm setting, that's very acceptable to me .... 

let this be clear, yes this amp has Hiss with high sensitivity headphones on high impedance, but let's do not forget it is very high power ( 4W into 300ohm ) and that is translated to not that much play with the volume knob, and a sense of effortlessness that I have never experienced with any other headphone amp. And when the music is playing, you can hear the hiss only on very quiet passages. ( If you listen to vinyl often, you know what I'm talking about ).

I'm not saying that it is acceptable, I think cayin must revise their copy a bit and propose a solution to make this amp truly universal.( make a low gain switch between preamp and amp is my best guess )

Now It can drive my aryas flawlessly with no hiss whatsoever, make the hd650 sing like it never did before, drive my kennerton magni where my head is vibrating along with the bass.... and all of that with that tube magik sound, wide soundstage, crystal clear highs, heavy bottom end, rich mid range...

And you can tube roll kt88, el34, 6l6.... and switch from Single Ended to Ultralinear for even more thump. And you can have it balanced if you like...

honestly, it is a great amp, I listen to It every day, and maybe could be amongst the very best, with a little engineering work for a MkII version


----------



## Fatdoi

I remember someone mentioned Utopia on this forum... anyone tried Utopia on this amp?


----------



## Gr3g277

Fatdoi said:


> I remember someone mentioned Utopia on this forum... anyone tried Utopia on this amp?



not yet.....

more to come later I hope this week


----------



## Fatdoi (Sep 9, 2020)

here in Australia, this new amp already @ close to 10% discount... wonder why

https://a1futureshop.com.au/index.php?route=product/product&product_id=1490&search=CAYIN


----------



## Gr3g277

Gr3g277 said:


> not yet.....
> 
> more to come later I hope this week




hello my friends,

as teased....






and with his friends...




As you can see, I saw a used first hand utopia... and the price was correct, so I couldn't resist XD 
damn that hobby... 

I was a bit hesitant because of the hiss issue, and the focals high sensitivity.

But I'm glad I took my chance here.

I'm putting this out of the table now, yes I can hear hiss in balanced medium setting. In single ended, I can barely hear it.
I would say the level is about the same as I get with my HD650

To be honest , the hiss doesn't bother me anymore, Now that I have understood how this amp behaves.

I am in audio Bliss right now.

I want to say, the pairing is really good because of what I am hearing right now, but I dont't have that much points of reference to compare to.
I will try my asgard 3 and my marantz HD-Dac1 as well later.

I will try my best to describe what I am hearing now with the HA-6a equipped with 6l6wgc blackplates and sylvania 6189. SE out and impedance switch on the mid setting.
My point of reference will be My Hifiman Arya, that I know well and love.

First thing I hear, is the soundstage is more Intimate than my arya, but in no way small or congested. I am still hearing far out of my head, just not as big .
layering is incredible, instruments placement is far better than the arya. Everything sounds more in focus, spatial information are better resolved.
In comparison, my arya sounds wider,airier and more distant, also more blurry, but not in an unpleasant way,and also a lot bigger

Tonality is spot on, in fact very close to the arya's, I'm not good at describing tonality differences, but what I hear is a fuller midrange,a lot of details, and very good treble, I don't experience any harshness. Cimbals are amazing
Bass is incredibly impactful, maybe not as deep as the planar, but , more body in the mid bass, drums impact are great. It is not lacking in any way, and I am very satisfied.

Timbre and transients are great, microdynamics and plankton are insane, but here aryas are no slouch either.

Please take this as my personal experience, and I am not yet out of the honeymoon period....

My aryas are not going anywhere yet. I think the focal is better, but the aryas is different, I still love it and it is really confy, and not fatiguing, long listening sessions goes like nothing with them.

Now I will try to describe how the amp interacts with the utopia,

I think the mid setting for impedance matching, gives a subtle boost in the low end, but it could be placebo. Sounds great on the L impedance setting as well ( with a blacker background )

The utopia's are really sensitive, about 3 to 4 clicks will give a plenty loud experience ! ( cayin please do a low gain option )
Switching from triode to ultralinear, the sound seems a bit cleaner,I gain punch and attack, But the sound stage become more "in-your face ".

Very nice indeed playing "long distance calling - aurora", when the drums kicks in, my head starts bobbing on it's own 

Now between single ended and balanced connection, this is a tricky one...differences are subtle, but are there, SE has less noise, but seems a tiny bit muddier in the lower mids. Balanced Out has a bit more gain, and seems cleaner with more impact.
It is tricky because it is really hard to have both outputs volume matched.

the utopia made those differences appear, I have to try the RCA IN vs XLR ( using those now )

Power tube rolling : 

Switching to the provided Gold Lions KT88

I get a crispier top end and the presentation becomes more impactful, also drier. Mid range "magik" is a bit gone especially In UL. Better in Triode but not el34 level. Overall this sounds more like good solid state to me. Good EDM is great in UL mode , a bit too piercing with heavy Metal music, very satisying on nicely mastered songs.
Bass is super tight and digs deep.

didn't like the provided EH el34 at all, shrill sounding and unpleasant mids

Switching to JJ EL34

Fuller mid bass and mids in general, top end seems rolled off a bit, great soundstage, pleasant sound overall, on the warm side of the force,  especially in triode.
Bass is big and rounder, not as controlled. 
Vocals are warm with plenty of texture, female vocals are gorgeous , here you get that tube sound !

Back to 6L6WGC blackplates

Best of both world IMO. Great details and imaging, a bit less full than the el 34, great extension on the top, natural tonality, tight bass, very good imaging.
It has also very good "drive" and "attack".

To sum things up, I love My new toy, but I am amazed at how well the aryas was holding the comparison. Still like the bigger/more distant/less precise stage for some stuff ( If someone here likes SUNN 0))  you should try with the arya... ).
I think the pairing with this amp and the utopia is great, the sound is incredibly full, and so precise.
I'll test my other amps as well to see how it compares.

Here you go folks. Thank you for reading until the end, excuse me If it was difficult to read, english is not my native language...

best 

greg


----------



## GU1DO

Gr3g277 said:


> hello my friends,
> 
> as teased....
> 
> ...


Cayin didnt offer to fix your amp ?


----------



## GU1DO

i guess till now nobody got a fixed unit , all have the hiss problem


----------



## Gr3g277

GU1DO said:


> i guess till now nobody got a fixed unit , all have the hiss problem


@Relaxasaurus got his back, and it was the same.
Still waiting for @kimdeug to receive his I think.
On my side, I will keep mine  unless there is an official recall from the company.

 i am enjoying thisway too much to let it go for month , with no guarantee that the problem is solved

Don't know if you noticed but i did put tube dampers on the pream tubes and it definitely helped with microphonics and weird noises
It also could be burn in because the hiss doesn't bother me as much as before.
Or Maybe im used to it i don't know

Honestly, the amp is silent with the very sensitive utopia in single ended mode on mid setting.

I have to concentrate hard to hear the hiss.but i can hear it.
Balanced it is noticeable, only without music.but i can hear it between tracks.

As you can see from my previous post i am enjoying almost all the functions of the amp.

To me I only have to put my headphones on and fire up this baby to know it is a end game setup


----------



## kimdeug

Gr3g277 said:


> @Relaxasaurus got his back, and it was the same.
> Still waiting for @kimdeug to receive his I think.
> On my side, I will keep mine  unless there is an official recall from the company.
> 
> ...


Congratulation my friend. 

Utopia is my one of favorite and on radar too. 
Very nice combo setup and awesome choice.
My unit is still on repair in Auckland/Local  repair shop.
Will post update here when receive.

OMG. More Expenses are coming: GTX 3090, Utopia, and RAV4 Prime hybrid 
Doing the brainstorm now I can make it happens to afford all of them)

Regards,
Kim


----------



## Andykong

Gr3g277 said:


> hello my friends,
> 
> as teased....
> 
> ...



Quick questions, upto the point where you stated "Power tube rolling : Switching to the provided Gold Lions KT88", the impression is based on stock KT88?

I assume you only receive the amplifier couple of days before you share your impression?

You didn't mention the Kennerton Magni, it didn't pair well with HA-6A?  Kennerton Thror is one of my reference headphone and I like it with HA-6A (KT88).  I assume the Magni pairs well with HA-6A but since I didn't heart it before, I might be wrong.


----------



## Relaxasaurus

Gr3g277 said:


> hello my friends,
> 
> as teased....
> 
> ...


Thanks a ton for the impressions! Don't know how I missed this post lol. You're right, if Cayin provided a low gain option that would be killer.

Now that winter is coming I can't wait to use this to heat my room again


----------



## JafoNYC

I've been on the journey for a tube HP amp - long term user of tube amps in 2 channel hi fi (Vintage McIntosh, Prima Luna). Almost went for the Cayin but after reading through this thread, was put off. Checked with the US distributer and even though they insisted upgraded  new units were coming in mid-September, couldn't identify what was being "fixed." I do know when it comes to tubes a low noise floor is everything - and what I read here there seems to be a real issue and it's sad the manufacturer doesn't seem to be standing behind the product.


----------



## Gr3g277

Andykong said:


> Quick questions, upto the point where you stated "Power tube rolling : Switching to the provided Gold Lions KT88", the impression is based on stock KT88?
> 
> I assume you only receive the amplifier couple of days before you share your impression?
> 
> You didn't mention the Kennerton Magni, it didn't pair well with HA-6A?  Kennerton Thror is one of my reference headphone and I like it with HA-6A (KT88).  I assume the Magni pairs well with HA-6A but since I didn't heart it before, I might be wrong.



Hi @Andykong 

Yes I was talking about the stock Kt88 ( genalex Gold Lions KT88 ) I said "switching to" because my impressions when listening to the utopia was with 6l6 power tubes.

No I have the amp since quite a while now, around march - april I think ( we already talked together on this forum if you can recall ), and the tubes are fully burned in

I didn't talk about the magni, It works well with the HA-6a sound wise, but it is not on the same level as my arya and now utopia.
Comparison wouldn't be fair. And Moreover, it is a closed back headphone.
The real problem is the hiss with the magni, as it is closed back, it makes it really noticeable, especially on the balanced output.
Magni is really super sensitive as well, and I use it mostly at my work with a small topping DX3 dac/amp. I think it is better than the focal elegia ( closed back )

I didn't hear the kennerton Thror yet, I hope to be able to some day. Not easy where I live, I have to go to Paris to be able to listen to some good headphones


----------



## Gr3g277

@Andykong 

Hey, I have a quick questions for you or the design team 

Do you know what is the heater voltage used for the 12AU7 preamp tubes ?

Are they wired for 6.3V or 12.6V operation ?

best


----------



## arftech

Seriously thinking about moving on from my current amp and is looking at this particular guy.  Can somebody comment on the synergy with the Auteurs?  I simply need a better amp for them to bring out the best performance from my headphones.  Thanks...


----------



## Relaxasaurus

arftech said:


> Seriously thinking about moving on from my current amp and is looking at this particular guy.  Can somebody comment on the synergy with the Auteurs?  I simply need a better amp for them to bring out the best performance from my headphones.  Thanks...


I absolutely love how the Aeolus sounds on this amp. If you don't mind using the single ended out to avoid hiss I think you will be very pleased.


----------



## arftech

Relaxasaurus said:


> I absolutely love how the Aeolus sounds on this amp. If you don't mind using the single ended out to avoid hiss I think you will be very pleased.



Wow, I'm reading the the posts about the hiss.  Cayin have not addressed this yet because I would prefer to run my Auteurs in balanced mode.


----------



## GU1DO

arftech said:


> Wow, I'm reading the the posts about the hiss.  Cayin have not addressed this yet because I would prefer to run my Auteurs in balanced mode.


Yes for the moment dont buy at all ,, even if it sound amazing though i didn't hear anything amazing ,, the hiss is a deal breaker.


----------



## arftech

GU1DO said:


> Yes for the moment dont buy at all ,, even if it sound amazing though i didn't hear anything amazing ,, the hiss is a deal breaker.


What’s recommended in the same prices category that has tubes?


----------



## Relaxasaurus

arftech said:


> What’s recommended in the same prices category that has tubes?


There are a couple of Allnic HPA-3000 GT's in the f/s forum. I haven't heard them personally but people seem to love them.


----------



## GU1DO

arftech said:


> What’s recommended in the same prices category that has tubes?


These are some i am looking at
Donald North Audio – Stratus
ALO audio – Studio Six
Dragon Inspire IHA-1 with the correct tubes should be something special 
Decware Taboo MKIV
ampsandsound Encore
Feliks Audio Euforia


----------



## GU1DO

Relaxasaurus said:


> There are a couple of Allnic HPA-3000 GT's in the f/s forum. I haven't heard them personally but people seem to love them.


did you release the vedio comparing the HA6A with the WA22 ?


----------



## Bonesy Jonesy

GU1DO said:


> These are some i am looking at
> Donald North Audio – Stratus
> ALO audio – Studio Six
> Dragon Inspire IHA-1 with the correct tubes should be something special
> ...


No Woo Audio products ?


----------



## Fatdoi

arftech said:


> What’s recommended in the same prices category that has tubes?


Not many if you want output transformer amp.... i've been looking around for sometime and still looking... unless you want to go up to 300B model


----------



## Bonesy Jonesy

Fatdoi said:


> Not many if you want output transformer amp.... i've been looking around for sometime and still looking... unless you want to go up to 300B model


Woo Audio WA5 is a good start if you want a 300B tube amp or if not then their WA22 or WA6 or WA6 SE.


----------



## Relaxasaurus

GU1DO said:


> did you release the vedio comparing the HA6A with the WA22 ?


Not yet, review notes are done though. I started recording in the new place and got pretty bad echo on the mic. Had to do some extensive sound deadening in the room first. Going to record this week


----------



## Relaxasaurus

GU1DO said:


> These are some i am looking at
> Donald North Audio – Stratus
> ALO audio – Studio Six
> Dragon Inspire IHA-1 with the correct tubes should be something special
> ...


Killer list. The Dragon from Moon has been on my sights for a while now. The DNA and Studio Six have been mainstays for a while and I wonder if they're getting a little long in the tooth, though I read Donald North is planning refreshes for the current models.

That reviewer Thomas & Stereo notes that with all the tube amps he's tested there seems to be a common theme- the older ones don't have the clarity and precision that modern designs do. That's one thing I noticed with the HA-6A vs the Woo WA22.


----------



## Zachik

Relaxasaurus said:


> Going to record this week


Something to look forward to, while watching entertaining and ridiculous reviews by Z (to pass time and get a few good chuckles)...


----------



## GU1DO

Bonesy Jonesy said:


> No Woo Audio products ?


Sorry i am not tube expert , these what was recommended to me


----------



## GU1DO

Guys finally my shipment is going back to the repair center , it was stuck in a weird way , i never experienced this delay or lack of information, and i hope Cayin improve there delivery options and not use the cheapest ways,,  Hopefully Cayin will honor the refund , because now i am sick and tiered with the whole situation.


----------



## Bonesy Jonesy

GU1DO said:


> Guys finally my shipment is going back to the repair center , it was stuck in a weird way , i never experienced this delay or lack of information, and i hope Cayin improve there delivery options and not use the cheapest ways,,  Hopefully Cayin will honor the refund , because now i am sick and tiered with the whole situation.


Terrible the way you have been treated by Messrs Cayin !


----------



## GU1DO

Bonesy Jonesy said:


> Terrible the way you have been treated by Messrs Cayin !


The things i didnt like the most . they said at first that they will ship me a new amp if there is any problem in my unit , after few weeks they decided to fix mine and ship it back, why ?????? they changed there mind and why i have to accept a fixed amp if it was dead on arrival , it is a huge company selling millions of units, 

About the delay tbh part of the problem is logistic though they used the worse way for shipping because i didnt pay for that shipping , though the first time they shipped it i paid around 300$ for shipping so i got in one week.


----------



## OctavianH

Even if at first I was interested in this amplifier I have decided not to buy it. I am sure we can find good amplifiers produced in Europe or US which are functioning as expected.


----------



## Fatdoi

OctavianH said:


> Even if at first I was interested in this amplifier I have decided not to buy it. I am sure we can find good amplifiers produced in Europe or US which are functioning as expected.


Please be brand specific not country


----------



## ThanatosVI

Is the price in the title accurate?
Here in Germany it's listed for 3600€ which is A LOT more than 2400$


----------



## GU1DO

ThanatosVI said:


> Is the price in the title accurate?
> Here in Germany it's listed for 3600€ which is A LOT more than 2400$


it depend from where you get it , in chinese websites it is sold for 2000$
From Cayin directly yes this is correct price + shipping for me it was +300$


----------



## ThanatosVI

GU1DO said:


> it depend from where you get it , in chinese websites it is sold for 2000$
> From Cayin directly yes this is correct price + shipping for me it was +300$


At this price it is really attractive,  do you by any chance know about international warranty from cayin?

Over here it costs 3600€
2400$ +300$ shipping is still a bargain in comparison. 

Initially I wanted a Primaluna but they are a pain to get in Germany


----------



## LTd head

ThanatosVI said:


> At this price it is really attractive,  do you by any chance know about international warranty from cayin?
> 
> Over here it costs 3600€
> 2400$ +300$ shipping is still a bargain in comparison.
> ...



I think France would be an option here in EU:
https://www.son-video.com/article/haute-fidelite-amplificateurs-amplis-casque/cayin/ha-6a


----------



## GU1DO

ThanatosVI said:


> At this price it is really attractive,  do you by any chance know about international warranty from cayin?
> 
> Over here it costs 3600€
> 2400$ +300$ shipping is still a bargain in comparison.
> ...


i sent mine to your country to be fixed so i guess your best source of information is Cayin local dealer if they will honor international warranty because international shipping is a nightmare


----------



## ThanatosVI

LTd head said:


> I think France would be an option here in EU:
> https://www.son-video.com/article/haute-fidelite-amplificateurs-amplis-casque/cayin/ha-6a


Omg thank you do much. 
At this price I might change my initial plans completely. 

I will contact them about shipping and warranty,  but even without it is 1100€ cheaper which makes it sort of "like used"

Does it always come with EL34 and KT88 tubes?


----------



## GU1DO

ThanatosVI said:


> Omg thank you do much.
> At this price I might change my initial plans completely.
> 
> I will contact them about shipping and warranty,  but even without it is 1100€ cheaper which makes it sort of "like used"
> ...


i hope you read the last few pages here before ordering ,, make sure you get a new unite without the hiss problem


----------



## ThanatosVI (Sep 28, 2020)

GU1DO said:


> i hope you read the last few pages here before ordering ,, make sure you get a new unite without the hiss problem


Still catching up but thanks for the warning

Is the hiss noticeable on the Meze Empyrean?


----------



## GU1DO

ThanatosVI said:


> Still catching up but thanks for the warning
> 
> Is the hiss noticeable on the Meze Empyrean?


 i didnt try them but probably no because they are planer


----------



## ThanatosVI (Sep 28, 2020)

GU1DO said:


> i didnt try them but probably no because they are planer


Well then I am totally fine, seems my amp journey is coming to an end.
I'm pretty ecstatic right now, that french price put it in a completely different league for me

Edit: I pulled the trigger now, thrilled to receive it soon


----------



## GU1DO

Relaxasaurus said:


> Not yet, review notes are done though. I started recording in the new place and got pretty bad echo on the mic. Had to do some extensive sound deadening in the room first. Going to record this week


Hi ,, you got HA300 to compare it with the HA6A ?


----------



## Relaxasaurus

GU1DO said:


> Hi ,, you got HA300 to compare it with the HA6A ?


I wish! I do not


----------



## GU1DO

Relaxasaurus said:


> I wish! I do not


oh someone in the HA300 thread said you do xD


----------



## ThanatosVI (Sep 30, 2020)

Relaxasaurus said:


> I wish! I do not


Sadness, was looking forward to the review.

The User mentioning it in the ha-300 thread probably confused it with the Woo Audio Wa22

I am also looking forward to that comparison!

In any case, does someone know a review which compared the Ha-6a and Ha-300?

The official site says something about a "Premium shield silver plated cable"
Is that about internsl cabling or does it actually ship with a special power cable?


----------



## Andykong

ThanatosVI said:


> Sadness, was looking forward to the review.
> 
> The User mentioning it in the ha-300 thread probably confused it with the Woo Audio Wa22
> 
> ...



Shield silver plated cable refer to internal cable.

I have posted this in HA300 thread, might post it here as well. @project86 had published a very detail HA300 review and he is working on HA-6A review right now, with a bit of luck, we should be able to read his review on Darko very soon.


----------



## Andykong

ThanatosVI said:


> Omg thank you do much.
> At this price I might change my initial plans completely.
> 
> I will contact them about shipping and warranty,  but even without it is 1100€ cheaper which makes it sort of "like used"
> ...



All HA-6A are shipped with matched pair of EL34 and KT88 tubes.  So unless it is second handed and the original owner has keep one of them, you can expect two set of power tube in the HA-6A package by default.


----------



## Andykong

Duplicated post, deleted.


----------



## ThanatosVI

Today it finally arrived.

Pictures don't do it justice, it looks way better in real life.
High quality finish. Built like a tank!

It was delivered with a cleaning cloth, gloves and 4 replacement fuses (2x2) which Was unexpected but really positive.

Sound impressions have to wait, however I was impressed right out of the box.

It's very likely that this will be my amplifier endgame


----------



## ThanatosVI (Oct 11, 2020)

So after 5 days I now switched the first time from the KT 88 to the EL34

Btw is tube burn in a thing?
And if so how long does it usually take to sound their best?


----------



## Gr3g277

ThanatosVI said:


> So after 5 days I now switched the first time from the KT 88 to the EL34
> 
> Btw is tube burn in a thing?
> And if so how long does it usually take to sound their best?


Hello ,

In my experience yes , tube burn in is really a thing, especially the GL kt88 take at least 50 h to settle in
The EH EL34 tube should sound good after 10h or so, but for me even after that time i didn't like them that much...

Tube rolling is a must with this one ! 

If you want to go that route, the small preamp tube have the most effect, look for mullard reissues, gold lions, NOS tubes like sylvania 6189, or RCA 5814A are really good as well, New production psvanes or TJ fullmusic are really good as well

For power tubes, don't look for NOS tubes, they are too expensive IMO. I go to a german based site called "tube amp doctor" they have a lot good stuff, and do a careful selection.

I have some psvanes on delivery, I'll report on them when they arrive.

BTW which headphones do you use with your HA-6A ?


----------



## ThanatosVI

Gr3g277 said:


> Hello ,
> 
> In my experience yes , tube burn in is really a thing, especially the GL kt88 take at least 50 h to settle in
> The EH EL34 tube should sound good after 10h or so, but for me even after that time i didn't like them that much...
> ...


Thx for the advice.

I use my Meze Empyrean with them and the pairing is amazing.

I love the GL KT88 so far, the EL34 smooths out the bass too much in many occassions (it still sounds amazing but not as good as with the KT88).
For certain music I even prefer the EL34, but since I listen to a Broad spectrum of genres, the KT88 fits better at the moment. 

Where can I read up on the sound character of the pre amp tubes?
I won't tube roll much and only to stuff that is readily available,  but being informed doesn't hurt


----------



## Gr3g277

ThanatosVI said:


> Thx for the advice.
> 
> I use my Meze Empyrean with them and the pairing is amazing.
> 
> ...



here is a good start on NOS 12au7 type tubes.

https://audiofool.reviews/tube-rolling-the-xduoo-ta-01b-ta-10-and-ta-20-12au7-amps/

I bet the empy's sounds good on this amp !
Do you notice any background hiss with them? what is the sensitivity rating for them ?


----------



## Articnoise

ThanatosVI said:


> So after 5 days I now switched the first time from the KT 88 to the EL34
> 
> Btw is tube burn in a thing?
> And if so how long does it usually take to sound their best?



Yes tubes sounds better after 50-100 hours.


----------



## ThanatosVI

Gr3g277 said:


> here is a good start on NOS 12au7 type tubes.
> 
> https://audiofool.reviews/tube-rolling-the-xduoo-ta-01b-ta-10-and-ta-20-12au7-amps/
> 
> ...


They sound amazing!

They have 32 ohm impedance with
100db@1mw/1kHz

The hiss is unfortunately there. It gets louder when turning the impedance switch to medium or high (it sounds best/more controlled on low to my ears anyways so not a big deal) also more noteable in ultralinear Mode than in triode.
It does not increase when turning the volume knob.

During music it is not noticeable,  however when watching movies or anything at low volumes it is.
It is very low in volume but it is undeniably there.

I don't have anything to "clean" my power, maybe it is related to that, or to the tubes. I didn't notice any humm difference between EL34 and KT88 .


----------



## Fatdoi

like to ask, when the unit is switched on and you brush your finger on the case, do you feel static electricity?


----------



## ThanatosVI

Fatdoi said:


> like to ask, when the unit is switched on and you brush your finger on the case, do you feel static electricity?


No I don't


----------



## Gr3g277

ThanatosVI said:


> No I don't


me neither, if you do, check your grounding


----------



## Andykong

ThanatosVI said:


> They sound amazing!
> 
> They have 32 ohm impedance with
> 100db@1mw/1kHz
> ...



Noise is directly related to power rating, the higher the power rating, the higher the noise.  HA-6A offers a very wide range of output power to make it flexibility to our users when they can match with different headphones.  To put this into context, with the same set of power tube the lowest output power setting is Triode mode + Low Impedance + Single-ended output (6.35mm), and the highest output power setting is Ultralinear mode + High Impedance + Balanced (XLR4 or 4.4mm). Roughly speaking, the later (UL+H+BAL) can be 7 higher than the first (TR+L+SE) setting.  That also explained why you hear more noise when you switch to a high impedance setting with a low impedance headphone.  

The table belows convert the power rating figures into Vrms so that we can compare them across different loading. 







To summarize, when using KT88, at Low impedance setting, Single-end delivers 7.16Vrms, Balanced delivers 8.76Vrms, but when you switch to High impedance setting, Balanced delivers 51.96Vrms, that is 7.26x of SE (low) or 5.93x of BAL (low).


----------



## ThanatosVI

Andykong said:


> Noise is directly related to power rating, the higher the power rating, the higher the noise.  HA-6A offers a very wide range of output power to make it flexibility to our users when they can match with different headphones.  To put this into context, with the same set of power tube the lowest output power setting is Triode mode + Low Impedance + Single-ended output (6.35mm), and the highest output power setting is Ultralinear mode + High Impedance + Balanced (XLR4 or 4.4mm). Roughly speaking, the later (UL+H+BAL) can be 7 higher than the first (TR+L+SE) setting.  That also explained why you hear more noise when you switch to a high impedance setting with a low impedance headphone.
> 
> The table belows convert the power rating figures into Vrms so that we can compare them across different loading.
> 
> ...


Thx for that technical explanation. 

Regarding triode/ultralinear Mode switch,  the msnual claims that it remembers the last used state, however mine always starts in triode mode.

Is my device faulty or is the manual wrong?


----------



## ThanatosVI (Oct 13, 2020)

Last time I already posted about the humm, so there isn't anything more to add. This is also the only negative point I could find about this amp.

So time for some sound impressions:

Background: I came from a Setup of
Android UUAP bit perfect -> Oppo Sonica -> Schiit Loki -> Meier Audio Corda Classic -> Norne Skraug cable -> Meze Empyrean( The corda classic is a mid fi Solid State amp, comparable to a Topping A90 or Schiit Jotunheim. It has a very neutral tone)

My current setup replaced the Corda Classic with the HA-6A.
I never owned a tube amp, nor an amp in that price range before.

Right from the get go (with KT88 in Triode mode) I noticed extremely good instrument separation, "tube magic" in the mids, guitars and vocals never sounded that addicting. Also bass guitars never sounded even remotely as good as here. The Staging has great depth (not witdh, which is still good). The amp has amazing detail retrieval and I noticed things I never heard before. This was the most surprising fact for me, considering that the corda classic is no slouch in it's league. Overall it has a very relaxing sound signature much like the Empyrean character. You simply sink into the music and forget the world around you. However it always stays engaging never gets boring or too smooth..
When switching to Ultralinear mode, the subbass becomes more noteable, very tight and textured, the extension is amazing. Also the highs receive quite some sparkle energy. This has overall solid state character but with just the right amount of tube magic. For me personally this is better than pure solid state.
I also really love the fact that the button is easily accessible on the front. It's not a "choose your favourite and done" I switch very frequently depending on the song.
Generally genres with string instruments and focus on vocals -> Triode mode
Modern electronic music (hardstyle, dubstep) -> Ultra linear

After a few days I switched to the EL 34 tubes.
In Triode mode they offered even more tube magic. Guitars and vocals sound magical, but for my taste it smooths out the edges too much. I really love my subbass which takes a hit. They have their upside but unless I have a phase when I listen only to a certain genre, the KT 88 are superior.
The KT 88 also offer better separation.

I think that this amp is just perfect for me. I use the Triode/Ultralinear feature A LOT, the amp is so versatile and gives me the feeling to always get the best sound possible for whatever I listen to.
Due to this feature I think that I might prefer this amp even to the "bigger brother" Ha-300, which might sound "too smooth" for modern electronic music.

Maybe I start some tube rolling around christmas.
Starting with the preamp tubes, while keeping the Generalex Gold Lion KT88.
Any  recommendations on readily available (so likely current production) tubes?

Can someone describe the sound of gold lions, mullards, psvanes? (all the "cheap" reissues)
I don't plan to roll much, since I am actually really happy with the standard KT 88s, but preamp tubes are said to have the most impact anyways.

Which tubes give the best subbass (texture and quantity - importance in that order). Or give great subbass while retaining that mid magic that the standard Electro Harmonix 12au7 have?


----------



## GU1DO

Hi all, 

I just want to give a closer for my problem ,, few days ago i got refunded after cayin received there packge , hopefully i will revisit this amp after the hiss issue get sorted and i see more positive feedback, also i want to thank Mr.John who was the contact from Cayin, he was very patient with me.

Best regards.


----------



## kimdeug

GU1DO said:


> Hi all,
> 
> I just want to give a closer for my problem ,, few days ago i got refunded after cayin received there packge , hopefully i will revisit this amp after the hiss issue get sorted and i see more positive feedback, also i want to thank Mr.John who was the contact from Cayin, he was very patient with me.
> 
> Best regards.


Good to know that Cayin has provided refund. In my case, the local repair service has ordered the new board and will replace it. But I have very strong suspicious that it will not fix the problem. next will be refund. 3 months repair waiting is quite hard. I do not understand why Cayin until now did not recall the unit and done proper investigation. Instead of that they prefer the local repair shops all around the world to fix their problems. If it is a faulty parts it can help, but if it is a poor circuit design the local shop will not be able to fix it. Now Cayin try to convince me it is a a faulty parts, but from my  radio experience it looks  like poor circuit design. I have asked to measure on oscilloscope how clean DC power comes to driver tube 12AU7 (from my point the problem around this area), Also I am thinking to made bypass, take the driver stage from another OLT amp and connect to the Cayin amplification part (KT88) and vise versa to find where is the problem. Regards, Kim


----------



## Gr3g277

kimdeug said:


> Good to know that Cayin has provided refund. In my case, the local repair service has ordered the new board and will replace it. But I have very strong suspicious that it will not fix the problem. next will be refund. 3 months repair waiting is quite hard. I do not understand why Cayin until now did not recall the unit and done proper investigation. Instead of that they prefer the local repair shops all around the world to fix their problems. If it is a faulty parts it can help, but if it is a poor circuit design the local shop will not be able to fix it. Now Cayin try to convince me it is a a faulty parts, but from my  radio experience it looks  like poor circuit design. I have asked to measure on oscilloscope how clean DC power comes to driver tube 12AU7 (from my point the problem around this area), Also I am thinking to made bypass, take the driver stage from another OLT amp and connect to the Cayin amplification part (KT88) and vise versa to find where is the problem. Regards, Kim


Do you know what parts needed to be changed , by your local shop ?


----------



## ThanatosVI

So the wife bought me a pair of Electro harmonix 12au7 gold,  tube rolling starts earlier than expected. 

How long do these usually take to burn in?


----------



## Andykong

ThanatosVI said:


> So the wife bought me a pair of Electro harmonix 12au7 gold,  tube rolling starts earlier than expected.
> 
> How long do these usually take to burn in?



Your wife understands your hobby and bought you a pair of 12AU7 as present?  That 's some serious blessing, because I sure won't have the knowledge to buy a lipstick for my wife. 

You don't need very long hours to burn in the vacuum tubes, run it for 20 hours and you can form your impression already, and the audio signature will be fairly stable after 50 hours.  According to the vacuum tube hobbyist, the burn in process actually continuous all through the life of the vacuum tubes and their tubes sound best the day before it died.


----------



## Andykong

kimdeug said:


> Good to know that Cayin has provided refund. In my case, the local repair service has ordered the new board and will replace it. But I have very strong suspicious that it will not fix the problem. next will be refund. 3 months repair waiting is quite hard. I do not understand why Cayin until now did not recall the unit and done proper investigation. Instead of that they prefer the local repair shops all around the world to fix their problems. If it is a faulty parts it can help, but if it is a poor circuit design the local shop will not be able to fix it. Now Cayin try to convince me it is a a faulty parts, but from my  radio experience it looks  like poor circuit design. I have asked to measure on oscilloscope how clean DC power comes to driver tube 12AU7 (from my point the problem around this area), Also I am thinking to made bypass, take the driver stage from another OLT amp and connect to the Cayin amplification part (KT88) and vise versa to find where is the problem. Regards, Kim



I hope other users are not forming a biased opinion because of the complaints in this thread.  For the record, we also offered full refund to @Relaxasaurus.  We feel sorry to Relaxasaurus for taking him 2 months of waiting, and we think it's unreasonable to ask him to wait for another 2-3 months, we offered full refund so that we can collect the HA-6A from him and send it back to China for inspection.  Relaxasaurus rejected our offer.


----------



## Fatdoi

Andykong said:


> I hope other users are not forming a biased opinion because of the complaints in this thread.  For the record, we also offered full refund to @Relaxasaurus.  We feel sorry to Relaxasaurus for taking him 2 months of waiting, and we think it's unreasonable to ask him to wait for another 2-3 months, we offered full refund so that we can collect the HA-6A from him and send it back to China for inspection.  Relaxasaurus rejected our offer.


Hi Andy..... if Cayin was able to fix the hissing complaint, I'm sure the owners would want to keep their amps... so far I still haven't read on this thread the fix is found and corrected.


----------



## Andykong

Fatdoi said:


> Hi Andy..... if Cayin was able to fix the hissing complaint, I'm sure the owners would want to keep their amps... so far I still haven't read on this thread the fix is found and corrected.



Given the uncertainties and inefficient logistic system worldwide, we think a full refund to customer and collect the amplifier from further study is the best option.


----------



## ThanatosVI

Andykong said:


> Your wife understands your hobby and bought you a pair of 12AU7 as present?  That 's some serious blessing, because I sure won't have the knowledge to buy a lipstick for my wife.
> 
> You don't need very long hours to burn in the vacuum tubes, run it for 20 hours and you can form your impression already, and the audio signature will be fairly stable after 50 hours.  According to the vacuum tube hobbyist, the burn in process actually continuous all through the life of the vacuum tubes and their tubes sound best the day before it died.


Nah I wrote on a list "possible gifts" with links on where to buy.

We both have such lists for birthdays, christmas and such.


----------



## Fatdoi

ThanatosVI said:


> Nah I wrote on a list "possible gifts" with links on where to buy.
> 
> We both have such lists for birthdays, christmas and such.


a very pragmatic couple... thumbs up


----------



## ThanatosVI

So after some hours with my new pre amp tubes I will leave some impressions. 

The New tubes are Electro harmonix 12au7 Gold.
They are very clear,  slightly bright with great extension on both sides. Feels like a completely different amp with those.
Since they are so clear and "solid state" like, they feel slightly thin at times. 

The sound may be a matter of taste but the universally good news is, that the Hum Sound is nearly completely gone with them.
It has been significantly less than the stock tubes right from the moment I first inserted them, but now after 20-30 hours on them the hum is nearly completely gone (low impedance,  triode mode, xlr out)


----------



## ThanatosVI

I know that I nearly write to myself in here ny now, but I got Updates regarding the hum Sound.

Today I rolled back to the stock tubes (Experimenting with a different DAC)
At first I had a huge noise on the left channel, which made me fear I destroyed something. 

I then switched to the EH Gold again, where everyghing was silent.
Back to the stock tubes, again huge hum on the left channel
Then I just switched tubes left and right channel, and I am finally back to the little hum I had when I first got the amp 

So to me it seems that I simply have a noisy stock tube and the hum could be fixed by replacing it. And that the left tube Socket is more Prone to noise(whixh makes sense to an amateur like me since it is in the middle of the amp)

Of course this might only hold true for planars, and dynamics might get the hum even with dead silent tubes


----------



## Gr3g277 (Oct 29, 2020)

ThanatosVI said:


> I know that I nearly write to myself in here ny now, but I got Updates regarding the hum Sound.
> 
> Today I rolled back to the stock tubes (Experimenting with a different DAC)
> At first I had a huge noise on the left channel, which made me fear I destroyed something.
> ...


hello my friend,


yes I can confirm that too, mine is more "sensitive" to different stuff like noise, hum, microphonics on the left channell as well.
It is a bit strange cause I have a quad of sylvania 6189, and i found that 3 of them were not usable on the left channel, but good on the right channel.
I definetely think the preamp section is picky with with the tubes.

I think I will work on opening the beast and drawing a basic schematic of what is going on in the preamp section.
maybe I will try upgrading the caps as well... I heard that could give good results regarding hum and microphonics

In the meantime, I am still enjoying this amp so much, I scored a pair of 60's RCA 5814A blackplates triple mica, and they are my favourite so far !


----------



## ThanatosVI

Gr3g277 said:


> hello my friend,
> 
> 
> yes I can confirm that too, mine is more "sensitive" to different stuff like noise, hum, microphonics on the left channell as well.
> ...


Can you describe the sound of the RCA 5814A blackplates triple mica?
Since you only need two I consider them affordable. 
Are they rather warm or clear, how good is the extension on both sides etc.
Is there something you like in particular about their sound?


----------



## Gr3g277

ThanatosVI said:


> Can you describe the sound of the RCA 5814A blackplates triple mica?
> Since you only need two I consider them affordable.
> Are they rather warm or clear, how good is the extension on both sides etc.
> Is there something you like in particular about their sound?



I find them comparable to the 6189,

compared directly to the stock EH 12au7, they are definitely warmer but not overly warm as well, I find them pretty neutral, with good extensions on both side
the overall sound is more "liquid", and fairly detailed.
soundstage and separation are good, but no better than the 6189.here I think the EH are a bit more upfront

If you Go on the NOS route , please buy from a reputable reseller, or if you go on ebay, buy only tubes that test good


----------



## ThanatosVI

Gr3g277 said:


> I find them comparable to the 6189,
> 
> compared directly to the stock EH 12au7, they are definitely warmer but not overly warm as well, I find them pretty neutral, with good extensions on both side
> the overall sound is more "liquid", and fairly detailed.
> ...


Thx for the impressions 

I am not sure yet, if I will go the NOS Route.
However I really like to read about some sound signatures.
Therefore it would be much appreciated if you could share your experience.
I am also interested in the sound of some reissues.
Someone recommended Gold lions, Mullard and the EH Gold which I already have.

For now I will order from tubeampdoctor.
Cayin Support recommended https://btb-elektronik.de/ as well.

Didn't you also order some PSVane not too long ago?


----------



## Gr3g277

ThanatosVI said:


> Thx for the impressions
> 
> I am not sure yet, if I will go the NOS Route.
> However I really like to read about some sound signatures.
> ...



I did receive the psvanes but one of them is too noisy to use in this amp, I bought them from china, and I have to send them back before i can get a replacement.
too bad cause the sound was very promising !

what i tested so far for preamp tubes : ( i also have a primaluna speaker amp that in which I can use them  )

*stock EH12au7 *: good tube in ha-6a, a bit bright and upfront for my liking
*JJ ecc802S* : too noisy for ha-6a, warm and rich, wooly bass in primaluna, short on the top
*primaluna shuguang 12au7* : too noisy for ha-6a, bright-neutral, upfront, 2D soundstage, not my cup of tea
*GE 6189 & sylvania 6189* : low noise, some are a bit microphonic, very good in ha-6a, neutral to warmish signature, a bit rich mids good extension top to bottom, very good details, 
*RCA 5814A* blackplates triple mica : noise level is same as 6189, low microphonics, neutral sound, great mids, great extension, very balanced
*Psvane 12au7-S art series* : 1 tube was very noisy from the start,the other as low noise as the 5814, trying to listen a bit, it was quite promising, with brighter signature like the EH, but very good soundstage, and less upfront presentation, I have to try them in the speaker amp, to see if the noise does bother me..


tube amp doctor is my primary source for tubes, you can't go wrong with them !!

I don't have experience with btb-elektronic, I will look at what they have...

PS: don't go too far down the rabbit hole of tube rolling.....


----------



## ThanatosVI

Gr3g277 said:


> I did receive the psvanes but one of them is too noisy to use in this amp, I bought them from china, and I have to send them back before i can get a replacement.
> too bad cause the sound was very promising !
> 
> what i tested so far for preamp tubes : ( i also have a primaluna speaker amp that in which I can use them  )
> ...


Which primaluna amp do you have?
I initially planned on getting an Evo 300 but in the end I decided on the Ha-6a 

Did you ever compare the headphone out with the Ha-6a?

Thx for the tube sound impressions,  seems like it is challenging to find tubes that are silent enough.


----------



## Gr3g277

ThanatosVI said:


> Which primaluna amp do you have?
> I initially planned on getting an Evo 300 but in the end I decided on the Ha-6a
> 
> Did you ever compare the headphone out with the Ha-6a?
> ...



I have the basic prologue classic integrated amp, so no headphone out unfortunately.

I did try the speaker out with a balanced adapter cable, with my arya's and it sounded pretty darn good, but it has waaay too much gain without the proper divider network .

So not usable as is as a headphone amp.
That said the cayin sounds better....

I have some mundorf caps coming for the primaluna  , if it makes really a difference, I will maybe try upgrading the caps in the ha 6a...

I looked inside and the caps layout is quite unconventional ! 2 .22uf paralleled coupling caps.. never seen that !  

1 electrolityc dc blocker, 1 .1uf bypassing it.
And a cathode resistor bypass. The tube sockets are pretty crowded !

The caps are realcaps , the same you find in the dialogue premium stuff from PL.
They changed them in the new EVO series.

I've read somwhere on the web a guy was getting hiss and microphonics with headphones on his primaluna (wich has realcaps) , upgraded all those to good metal film oil caps, and boom, no more hiss or microphonics....

Hummm, i don't want to void my warranty though....

Just some food for thought here.


----------



## kimdeug

Andykong said:


> I hope other users are not forming a biased opinion because of the complaints in this thread.  For the record, we also offered full refund to @Relaxasaurus.  We feel sorry to Relaxasaurus for taking him 2 months of waiting, and we think it's unreasonable to ask him to wait for another 2-3 months, we offered full refund so that we can collect the HA-6A from him and send it back to China for inspection.  Relaxasaurus rejected our offer.


Hi Andykong

Thanks for reply.
The issue is:  that I really want this amp, but don't want to hear hiss/humm noises for 2500USD I have paid for.
After waiting 3 months (from 27July since I have brought unit back to the seller shop) until now
 there is no any information regarding to my case.
I was patiently waiting 3 months, hoping that the hiss/humm problem will be fixed.
I think 3 months is long enough time to bring this unit to china and back.
I still did not received the money back and no unit on hand.
It is easy decision: If problem is fixed I will keep the unit. If not -Refund.
Just waiting period is too long.
And neither Cayin or my local repair shop can not provide the clear information about the progress or what was wrong.

Regards,
Kim


----------



## Andykong

@kimdeug please contact your agent again.  From the latest email we received, your HA-6A is on the way back to you, I am surprised that the Sales agent didn't contact you and give you the tracking number.   Maybe you can give them a call to find out the delivery arrangement?


----------



## ThanatosVI

Borrowed from the HA-300 thread, here is John's review of the Ha-6a. 

https://darko.audio/2020/10/moving-upfield-the-cayin-ha-6a/

Excellent read, further strengthening my impression that this amp might be superior to higher end amps like the HA-300 for my personal use case.


----------



## Gr3g277

ThanatosVI said:


> Borrowed from the HA-300 thread, here is John's review of the Ha-6a.
> 
> https://darko.audio/2020/10/moving-upfield-the-cayin-ha-6a/
> 
> Excellent read, further strengthening my impression that this amp might be superior to higher end amps like the HA-300 for my personal use case.




yes, very good review, thanks for the link !

I have the utopia, and I want to precise that the reviewer used the a balanced cable, and indeed in medium impedance, it is a bit too much for this particular headphone.
On single ended on the other hand, I find the medium impedance setting to raise the low medium just a bit, and make them sound a little fuller, but the bass stays pretty tight and very well controlled IMO

concerning noise floor, I agree with the reviewer, knowing that low Z single ended, triode, is the quietest , and Mid Z single ended is about the same noise level as balanced Low Z.

the sonic capabilities of that amp are juste great ! If you have a hd650 or hd800 you have to hear it SE triode High Z. it is unblievable how good this amp make them sound .
I personnally don't like beyers but I bet a 600ohms beyer would be great as well !


----------



## Andykong

Gr3g277 said:


> yes, very good review, thanks for the link !
> 
> I have the utopia, and I want to precise that the reviewer used the a balanced cable, and indeed in medium impedance, it is a bit too much for this particular headphone.
> On single ended on the other hand, I find the medium impedance setting to raise the low medium just a bit, and make them sound a little fuller, but the bass stays pretty tight and very well controlled IMO
> ...



A lot of users believe the HD800 must be driven by balanced in order to sound good, but IMHO, that is the case only when the single-end output is not powerful enough to drive the HD800 satisfactory, so I agree with your observation.

I have come across numerous setups that can drive the HD800 to display impressive soundstage, layering, and imaging, with class leading resolution and natural timbre, because it a monitor headphone by nature, but I find it difficult to make the vocal of HD800 sounds full with body and emotion.  Driven by a strong single-end amplifier might lower the channel separation by boosted the focus and improved the vocal presentation, and the harmonic characteristics of vacuum tube, especially in Triode mode, also contributed to this significantly.  The single-end Triode mode output of HA-6A with KT88 at High impedance is 38.7Vrms, a very high output by  any standard, and probably exceeded the output rating of a lot of Solid State headphone amplifier at balanced configuration.


----------



## ThanatosVI

Currently trying to read up on some upgrade tubes which are not NOS.

Seems like Cayin already made excellent choices regarding stock tubes.

I didn't find a single current production recommendation that beats the Gold Lion KT88.
And regarding EL34 I only found recommendations for the Genalex Gold Lion KT77 which is said to be somewhere in between typical EL34 and KT88 Sound. Tbh that sounds quite interesting to me.
Of course I found a few Single Statements where someone prefered a different tube, but nothing that is widely regarded as better.

The 12au7 is harder, there I've found tons of recommendations, therefore I tried to get some impressions over here:
https://www.head-fi.org/threads/new-production-12au7-tubes.945875/

Widely recommended in 2011 was the PSVane 12au7.
Cayin themselves recommended EH gold, mullards and Gold lions.

I must say, the EL34 Sound a lot better with the EH Gold 12au7 than paired with the stock tubes


----------



## BLmusic

Andykong said:


> @kimdeug please contact your agent again.  From the latest email we received, your HA-6A is on the way back to you, I am surprised that the Sales agent didn't contact you and give you the tracking number.   Maybe you can give them a call to find out the delivery arrangement?


Andy, 
Is the hiss/humm issue been resolved?


----------



## kimdeug

BLmusic said:


> Andy,
> Is the hiss/humm issue been resolved?


My unit on the way back from China to New Zealand. 
Still in transit to destination country.
Not sure it is a new unit or repaired one.
I will post my impression here as arrived.
BTW. I am looking all replays on this discussion.
Thanks a lot for your support.

Gr3g277 -your findings are very valuable. Keep rolling.

Regards,
Kim


----------



## Ethereal Sound

Has anyone ever used this amplifier with the Susvara? I'm interested but want to know if it will sufficiently power them.


----------



## Fatdoi

Ethereal Sound said:


> Has anyone ever used this amplifier with the Susvara? I'm interested but want to know if it will sufficiently power them.



someone's early post wrote this amp can power HE6SE so i think it should be able to drive Susvara


----------



## dadracer2

Andykong said:


> A lot of users believe the HD800 must be driven by balanced in order to sound good, but IMHO, that is the case only when the single-end output is not powerful enough to drive the HD800 satisfactory, so I agree with your observation.
> 
> I have come across numerous setups that can drive the HD800 to display impressive soundstage, layering, and imaging, with class leading resolution and natural timbre, because it a monitor headphone by nature, but I find it difficult to make the vocal of HD800 sounds full with body and emotion.  Driven by a strong single-end amplifier might lower the channel separation by boosted the focus and improved the vocal presentation, and the harmonic characteristics of vacuum tube, especially in Triode mode, also contributed to this significantly.  The single-end Triode mode output of HA-6A with KT88 at High impedance is 38.7Vrms, a very high output by  any standard, and probably exceeded the output rating of a lot of Solid State headphone amplifier at balanced configuration.


I think the use of a SET amp with the HD800S is the best I have ever heard from that headphone so far and gave vocals a quality I have only heard bettered on the HE1.


----------



## ThanatosVI

Did anyone ever try the Ha-6a with a PS Audio stellar power plant 3?
And if so, was it less sensitive to tube noise then?


----------



## Gr3g277

ThanatosVI said:


> Did anyone ever try the Ha-6a with a PS Audio stellar power plant 3?
> And if so, was it less sensitive to tube noise then?



No I don't have a power regenerator, and never had the chance to test one.

I have only a filtered power brick from SUPRA Cables, and it does not make any difference in noise levels for this amp. 
Maybe the PS Audio could work, but I am not sure it would....It would be interesting to know your findings if you give it a try !

I always thought that ps audio products where very interesting, but the entry ticket leap is pretty steep...


@kimdeug did you receive your fixed amp already ?


----------



## ThanatosVI

Gr3g277 said:


> No I don't have a power regenerator, and never had the chance to test one.
> 
> I have only a filtered power brick from SUPRA Cables, and it does not make any difference in noise levels for this amp.
> Maybe the PS Audio could work, but I am not sure it would....It would be interesting to know your findings if you give it a try !
> ...


The PS Audio P3 will be the last step on my journey, but since the entry Ticket fee is quite steep it will take a while.

When I get one I will report my findings but this will be some time next year.


----------



## kimdeug

Not yet.
Should be this week.

@kimdeug did you receive your fixed amp already ?
[/QUOTE]


----------



## skylinekursk

Hum issue is still in new batches?


----------



## ThanatosVI

Did anyone try the Audeze LCD-4 with this amp?


----------



## skylinekursk

How is sound signature? Is it bright/neutral or dark with lamp change?


----------



## ThanatosVI

skylinekursk said:


> How is sound signature? Is it bright/neutral or dark with lamp change?


Depends on the tubes you change it to.
With stock tubes it's definitely a neutral sound signature,  like it's common among new high end tube amp Releases.


----------



## kimdeug

skylinekursk said:


> Hum issue is still in new batches?


Has not receive my yet.


----------



## ThanatosVI

Gr3g277 said:


> No I don't have a power regenerator, and never had the chance to test one.
> 
> I have only a filtered power brick from SUPRA Cables, and it does not make any difference in noise levels for this amp.
> Maybe the PS Audio could work, but I am not sure it would....It would be interesting to know your findings if you give it a try !
> ...


So my ps audio stellar p3 is on its way, should be able to report the results "soon"


----------



## skylinekursk

going to order HA6A to my Empyrean


----------



## ThanatosVI

skylinekursk said:


> going to order HA6A to my Empyrean


Excellent combo


----------



## skylinekursk

ThanatosVI said:


> Excellent combo


I like Audeze house signature and I will have lcd4 one day, but is it possible to get such a lush and bassy sound on HA6A with Empyrean? Also I be very grateful if you can say how heavy (metal) music sound on HA6A? Is it enough speed for average speed tracks (less than 200 bpm)? 
Thanks in advance!


----------



## Sunset1982

skylinekursk said:


> going to order HA6A to my Empyrean





ThanatosVI said:


> Excellent combo



Any suggestions for some fitting tubes with the empyrean or are the stock tube already that good with the empys? What DAC would you guys suggest for the Empy/Ha6a combo? I'm thinking of getting a chord qutest...


----------



## Sunset1982

has anybody here had the chance to compare the HA6A against the Feliks Euforia 20th Anniversary Edition?


----------



## ThanatosVI (Nov 26, 2020)

Sunset1982 said:


> Any suggestions for some fitting tubes with the empyrean or are the stock tube already that good with the empys? What DAC would you guys suggest for the Empy/Ha6a combo? I'm thinking of getting a chord qutest...


I'd say the stock tubes are already great, especially the Gold lion KT88.
I switched the EH 12au7 to EH golds. The golds having slightly more extension to both sides and also a little more bass.

I will roll some more im the future but for now it's already great.

Regarding DAC, after hearing the Rockna Wavelight, it's hard to recommend anything below.

However,  I used an Oppo Sonica before, which was still great with stock tubes, but sounded a little bright with the EH 12au7 golds. Guess that is just a personal preference thing.


----------



## Newsee

ThanatosVI said:


> I'd say the stock tubes are already great, especially the Gold lion KT88.
> I switched the EH 12au7 to EH golds. The golds having slightly more extension to both sides and also a little more bass.
> 
> I will roll some more im the future but for now it's already great.
> ...


Nice new avatar


----------



## ThanatosVI

Newsee said:


> Nice new avatar


Thx mate - nice new Empyrean you got there


----------



## Gr3g277

skylinekursk said:


> I like Audeze house signature and I will have lcd4 one day, but is it possible to get such a lush and bassy sound on HA6A with Empyrean? Also I be very grateful if you can say how heavy (metal) music sound on HA6A? Is it enough speed for average speed tracks (less than 200 bpm)?
> Thanks in advance!




the HA-6A sounds great with heavy metal, old school or modern, even in triode mode.

Ultralinear is best suited to that genre, more slam and speed, especially with kt88 tubes !!!
that's great about that amp, you listen to fast paced death or black metal, you go UL and KT88, then a shoegaze or indie rock track pops in the playlist, go back to triode mode for the extra mid-bass warmth and stage, then you swap kt88 for el34, and enjoy super lush mid range for some feminine jazz...

on tube rolling : got a pair pf psvanes 6CA7- TII, and I love them ! especially in triode mode, they are really good ! the sounds seems more "luminous" ( sorry I'm bad at audiophile adjectives) , tonaly rich, luminous mid range, great bass, very refined treble..; a strong contender IMO !


slight off-topic, but i can't resist : ( sorry for cable non believers, please be not offended )

I DIY'ed new cables for my utopias with some neotech pure OCC silver cables and furutech connector, and with this amp, I was able to tell the différences with the stock cable right away, more air more extension, greater definition in bass, better soundstage...

here is a picture of those beauties together 








listening to "nothing as the ideal" from all them witches now...  I am drawn into this great abbey road mix !! sounds incredible


----------



## skylinekursk

Received mine today! Need to be burn in but first impression is good, I like both triode and UL mode with KT88! 
No hiss with Empyrean!


----------



## Bonesy Jonesy

Gr3g277 said:


> the HA-6A sounds great with heavy metal, old school or modern, even in triode mode.
> 
> Ultralinear is best suited to that genre, more slam and speed, especially with kt88 tubes !!!
> that's great about that amp, you listen to fast paced death or black metal, you go UL and KT88, then a shoegaze or indie rock track pops in the playlist, go back to triode mode for the extra mid-bass warmth and stage, then you swap kt88 for el34, and enjoy super lush mid range for some feminine jazz...
> ...


Do you get any background hiss with your HA-6A which seems to be prevalent with the HA-6A on this forum ?


----------



## Bonesy Jonesy

skylinekursk said:


> Received mine today! Need to be burn in but first impression is good, I like both triode and UL mode with KT88!
> No hiss with Empyrean!


What made you choose the HA-6A over say the Cayin HA-300 (with 300B tubes) or one of the Woo Audio amps i.e. the WA5 and WA33 for instance ?


----------



## ThanatosVI

Bonesy Jonesy said:


> What made you choose the HA-6A over say the Cayin HA-300 (with 300B tubes) or one of the Woo Audio amps i.e. the WA5 and WA33 for instance ?


Probably the price, it's significantly cheaper than those other options.(that was my main reason, since I considered all of those mentioned ones as well)

For EDM and similar music, it could still be the better choice.


----------



## skylinekursk (Nov 30, 2020)

Bonesy Jonesy said:


> What made you choose the HA-6A over say the Cayin HA-300 (with 300B tubes) or one of the Woo Audio amps i.e. the WA5 and WA33 for instance ?


I had no chance to listen or compare but customization of HA6A Is amazing... switch from triode mode to UL every song is cost a LOT! so many signatures in one AMP


----------



## ThanatosVI

Gr3g277 said:


> the HA-6A sounds great with heavy metal, old school or modern, even in triode mode.
> 
> Ultralinear is best suited to that genre, more slam and speed, especially with kt88 tubes !!!
> that's great about that amp, you listen to fast paced death or black metal, you go UL and KT88, then a shoegaze or indie rock track pops in the playlist, go back to triode mode for the extra mid-bass warmth and stage, then you swap kt88 for el34, and enjoy super lush mid range for some feminine jazz...
> ...


which tubes are you using on that picture?


----------



## Gr3g277

Bonesy Jonesy said:


> Do you get any background hiss with your HA-6A which seems to be prevalent with the HA-6A on this forum ?



yes I do, mine was not sent for repair, as It bothers me only with high impedance headphones on balanced connection
utopias are very sensitive, and it is silent in low impedance setting with single ended connection, on medium setting the mid bass thickens a bit, and hiss is a bit noticeable on very low moments. Does not bother me though
Honestly I ditched balanced all together ( input/output ) and stick with SE in/out and everything is good.

I find balanced input to have too much gain and even some slight distortion on very low bass ( using my bifrost 2 as dac )
hiss is noticeably higher using xlr balanced out, I would say usable but definietely noticeable on low impedance, and bothering me on the medium setting.

that is true with most sensitive headphones. I also own a hifiman arya, and use balance out for the added power with no hiss whatsoever due it's low sensitivity ( 90dbd/mw )

so my advice is mind your pairing ! this is a very powerful amp !




ThanatosVI said:


> which tubes are you using on that picture?



on that picture i am using sylvania 6189 as input tubes, and psvanes 6CA7-TII as power tubes
I like that pairing a lot 

@ThanatosVI , have you received the ps audio power plant ?


----------



## ThanatosVI

Gr3g277 said:


> yes I do, mine was not sent for repair, as It bothers me only with high impedance headphones on balanced connection
> utopias are very sensitive, and it is silent in low impedance setting with single ended connection, on medium setting the mid bass thickens a bit, and hiss is a bit noticeable on very low moments. Does not bother me though
> Honestly I ditched balanced all together ( input/output ) and stick with SE in/out and everything is good.
> 
> ...


Yes I received the power plant last friday, but I decided on custom nrg cables, which still need a few weeks.

So for now I don't have a power cable long enough to use it with the amp.
Using the power plant only for the DAC brings already ridiculous results. This is without exageration one of the most obvious changes one can do to a System


----------



## Gr3g277

nooooo, please don't say that, those things are way to dangerous for my wallet....
happy to hear that it bring obvious improvements on the table, I am now eager to hear if the improvements scales with the ha-6a....


----------



## ThanatosVI

Gr3g277 said:


> nooooo, please don't say that, those things are way to dangerous for my wallet....
> happy to hear that it bring obvious improvements on the table, I am now eager to hear if the improvements scales with the ha-6a....


I will make sure to let you know.
3 weeks from now they could be here.


----------



## skylinekursk

Forgot to say it could be helpful with hiss -I’m using dh labs red wave power cable and Igalvanic3 by ifi. Tried all gains using 6.3 output - no hiss at all. Dac connected trough RCA


----------



## LTd head

Please, try high impedance headphones


----------



## skylinekursk

LTd head said:


> Please, try high impedance headphones


Sorry but I have only Empyrean... anyway they are quite sensitive with 100 dB


----------



## skylinekursk

does anyone like el34 more than kt88?


----------



## ThanatosVI

skylinekursk said:


> does anyone like el34 more than kt88?


@Relaxasaurus does if I recall correctly


----------



## kimdeug

skylinekursk said:


> Received mine today! Need to be burn in but first impression is good, I like both triode and UL mode with KT88!
> No hiss with Empyrean!



Congrats my friend.
Welcome to the Ha-6A club.
I am Russian too, but living in New Zealand now.
Glad to see someone from motherland.
BTW still waiting my unit from repair, since 27 July (
Have bought few tubes GEC KT88, Gold Lion KT88 (made in UK Luxman branded), Ratheon 6L6 and few 12AU7 pairs (Amperex. Genalex, EH gold pin)
Just need the Cayin HA-6A back.
Was listening Empyrean in the shop (Copper version) with money on hand to buy, but...
Have around 2 hours listening session to compare side by side with Audeze 3 , 4, Focal Utopia, ZMF Verite, Sennh HD820 etc.
Have found that Empyrean is too neutral for me, ZMF Verite is not too far from my ZMF Auteur, I like more LCD-X than LCD-3
The winner for my ears was Focal Utopia and Audeze -4, but with LCD-4 after 30 minutes listening, I have fatigue due to trebles.
Which I do not have with Utopia and my HD800S.
Will post new findings here when HA-6A arrived.

Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> Congrats my friend.
> Welcome to the Ha-6A club.
> I am Russian too, but living in New Zealand now.
> Glad to see someone from motherland.
> ...


Waiting on it since 27th of Juli, that's terrible :O

So you could test the LCD-4 with the Ha-6a and considered it a good pairing?

I'm thinking about adding a LCD-4 to my Empyrean sometime next year or maybe the new Hifiman He-R10p


----------



## skylinekursk

kimdeug said:


> Congrats my friend.
> Welcome to the Ha-6A club.
> I am Russian too, but living in New Zealand now.
> Glad to see someone from motherland.
> ...



Nice to meet you and thanks! I enjoy my HA6a, after 12 hours of el34 burn in process they sound very good for me! Have no NOS tubes yet, but going to buy something in next few months! 
I tried LCD3 pre-fazor yesterday and I wasn't satisfy at all, soundstage is too intimate and huge lack in details to compare with Empyrean. The last one sounds very good with HA6A and my handcrafted by Russian Arkhipov's Laboratory tube DAC63 (based on 2xPCM63 K2 grade). I think DAC is the reason of synergy in system. I've got big bass goes to sub bas I've never heard before with Empy. Layering is amazing and trebles are not annoying for me. If you say LCD4 is brighter so I think they definitely  wouldn't be in my list.... I guess you can make Empy sounds more enjoyable by tube rolling!!! I tried it with my previous hybrid amp which has tube as a pre amp but rolling changed a lot anyway...  HA6A has much more room for rolling especially with mode change between UL and Triod!


----------



## skylinekursk

ThanatosVI said:


> Waiting on it since 27th of Juli, that's terrible :O
> 
> So you could test the LCD-4 with the Ha-6a and considered it a good pairing?
> 
> I'm thinking about adding a LCD-4 to my Empyrean sometime next year or maybe the new Hifiman He-R10p



Haha! Same thoughts in my head!!!


----------



## Bonesy Jonesy

kimdeug said:


> Congrats my friend.
> Welcome to the Ha-6A club.
> I am Russian too, but living in New Zealand now.
> Glad to see someone from motherland.
> ...


Thats terrible Kim having to wait all this time and totally unacceptable from any company !    
Also the hissing / buzzing issues of this Amp on top...Cayin should redesign this product ASAP to stop this problem, and have people return their HA-6A's back to Cayin for free for exchange of a redesigned Amp complete with full Cayin warranty !   
It clearly shows Cayin have a problem with this particular Amp !


----------



## ThanatosVI

skylinekursk said:


> Nice to meet you and thanks! I enjoy my HA6a, after 12 hours of el34 burn in process they sound very good for me! Have no NOS tubes yet, but going to buy something in next few months!
> I tried LCD3 pre-fazor yesterday and I wasn't satisfy at all, soundstage is too intimate and huge lack in details to compare with Empyrean. The last one sounds very good with HA6A and my handcrafted by Russian Arkhipov's Laboratory tube DAC63 (based on 2xPCM63 K2 grade). I think DAC is the reason of synergy in system. I've got big bass goes to sub bas I've never heard before with Empy. Layering is amazing and trebles are not annoying for me. If you say LCD4 is brighter so I think they definitely  wouldn't be in my list.... I guess you can make Empy sounds more enjoyable by tube rolling!!! I tried it with my previous hybrid amp which has tube as a pre amp but rolling changed a lot anyway...  HA6A has much more room for rolling especially with mode change between UL and Triod!


I reread kims post and it really does sound like he meant the LCD-4 was bright.

I never heard that claim before, the LCD-4 are among the darkest headphones in the flagship area (darker than the empy for example)

The Utopia on the other hand is bright.


----------



## skylinekursk

ThanatosVI said:


> I reread kims post and it really does sound like he meant the LCD-4 was bright.
> 
> I never heard that claim before, the LCD-4 are among the darkest headphones in the flagship area (darker than the empy for example)
> 
> The Utopia on the other hand is bright.



Same things I've heard before and for me it was big surprise!


----------



## kimdeug (Dec 3, 2020)

skylinekursk said:


> Same things I've heard before and for me it was big surprise!


3 years ago I came to the same shop to buy LCD-4.
But after intensive listening side by side with  LCD-2, 2C,  LCD-X, 3 and 4 with different amps (WA22, Burson etc).
I left the shop with LCD-X and LCD-2C
LCD-Xwas more energetic and LCD-2C was warmer sounding with less treble.
LSD-4 was very detailed, with better bass extension, but mids were recessed. And because of this the highs were more accentuated.
Combined all above with better clarity compare LCD-4 to LCD-X, after the long session with LCD-4 I have like ear ringing sound and all trebles with high details become more irritating.
While with LCD-X I never had this feeling.
Similar problem I had with Beyrodynamic DT1990 pro, which was fixed with swapping earpads from Mr Speakers Ether C and the thickest tuning foam inserted.
These earpads  are perfect for small lips mounting as all BeyroDynamics have. Highly recommended.

Regards,
Kim


----------



## skylinekursk (Dec 3, 2020)

kimdeug said:


> 3 years ago I came to the same shop to buy LCD-4.
> But after intensive listening side by side with  LCD-2, 2C,  LCD-X, 3 and 4 with different amps (WA22, Burson etc).
> I left the shop with LCD-X and LCD-2C
> LCD-Xwas more energetic and LCD-2C was warmer sounding with less treble.
> ...


Thank you for such detailed answer! Did you try lcd-x with HA6a? I had pair earlier but changed to Kennerton Thridi and now for Empyrean...
I miss lcd house sound.... and was looking on 4 but confused now after you posts!
I guess cut trebles with tube and cables is not a problem but recessed mids are awful stop factor


----------



## kimdeug (Dec 3, 2020)

Gr3g277 said:


> the HA-6A sounds great with heavy metal, old school or modern, even in triode mode.
> 
> Ultralinear is best suited to that genre, more slam and speed, especially with kt88 tubes !!!
> that's great about that amp, you listen to fast paced death or black metal, you go UL and KT88, then a shoegaze or indie rock track pops in the playlist, go back to triode mode for the extra mid-bass warmth and stage, then you swap kt88 for el34, and enjoy super lush mid range for some feminine jazz...
> ...


Nice cable man!!!

Look what has arrived recently )
brand new for 350 USD (refurbished as broken socket guide on one KT88)
Gold Lion KT88 (made in UK) x2
Amperex 12AU7 x3
Can not be more happier.

Kim


----------



## wishbon3

Pulled the trigger on one of these to compare to my custom CFA3 amp. Excited to hear the differences.


----------



## Gr3g277

kimdeug said:


> Nice cable man!!!
> 
> Look what has arrived recently )
> brand new for 350 USD (refurbished as broken socket guide on one KT88)
> ...



Man, those are Nice tubes !!

let's hope you receive tour amp back pretty soon, wanna read your impressions !

Haven't tried amperex 12au7 myself as well, so this will be interesting.

quick question, does anyone have tried a DC blocker between the mains and the amp , and / or a ground lift box ?

If yes does it help with noise floor ?


----------



## skylinekursk

Just listened music after extra burn-in hours on KT88 and I think amp become darker and darker.... it's not even 100 hours and sound could change again but anyway it's really darker than from the beginning. 
has someone same feeling during burn in process?


----------



## ThanatosVI

Damn I love this amp. Just changing the impedance setting can get you a different touch in sound signature.


----------



## wishbon3

Just got mine.... sound is insane, I didn't know my ZMFs could sound better, but Jesus.

There is a slight noise floor, but it's what I expect from tubes. It was bad with the USB input on my DAC, but with optical it's great.

Think I need to fix the noise in my USB connection, so I ordered an isolator, will see how it goes when it arrives.


----------



## ThanatosVI

wishbon3 said:


> Just got mine.... sound is insane, I didn't know my ZMFs could sound better, but Jesus.
> 
> There is a slight noise floor, but it's what I expect from tubes. It was bad with the USB input on my DAC, but with optical it's great.
> 
> Think I need to fix the noise in my USB connection, so I ordered an isolator, will see how it goes when it arrives.


Keep us updated on the USB Isolator.

The sound of this amp is amazing. 
I bought a drop thx 789 for my brother as christmas present and tested it yesterday.
It made me appreciate the Cayin even more since I instantly heard a huge difference. 

Obviously there is a huge price difference,  but the sound difference is equally big.


----------



## Zachik

wishbon3 said:


> Just got mine.... sound is insane, I didn't know my ZMFs could sound better, but Jesus.


What amp(s) have you been using until now?


----------



## wishbon3

Zachik said:


> What amp(s) have you been using until now?


Went from a90, to custom CFA3 based on Kevin Gilmore's design.

CFA3 is superb with many headphones, and is probably the best with Abyss. But this synergizes very well with my ZMFs, which I use primarily.


----------



## Zachik

wishbon3 said:


> Went from a90, to custom CFA3 based on Kevin Gilmore's design.
> 
> CFA3 is superb with many headphones, and is probably the best with Abyss. But this synergizes very well with my ZMFs, which I use primarily.


ZMF headphones just love tubes!


----------



## kimdeug

wishbon3 said:


> Just got mine.... sound is insane, I didn't know my ZMFs could sound better, but Jesus.
> 
> There is a slight noise floor, but it's what I expect from tubes. It was bad with the USB input on my DAC, but with optical it's great.
> 
> Think I need to fix the noise in my USB connection, so I ordered an isolator, will see how it goes when it arrives.


Congrats my friend.
Welcome to the Ha-6A club.


----------



## wishbon3

Adding the isolator removed all noise from my USB, this is almost completely silent now, glad I bought this amp, it's crazy good.


----------



## kimdeug

wishbon3 said:


> Adding the isolator removed all noise from my USB, this is almost completely silent now, glad I bought this amp, it's crazy good.


Good to know.
Is it any hissing/ humming noise? I have done intensive test with my one on Page 16-20. My USB signal was cleaned by Ifi USB 3.0 isolator. On top of this I have used power filters, DC blocker and Highly shielded power cables and RCA/ XLR shielded cables too. And have got  around 20dB humm/hissing noise. For control I have plugged to my other different headphone amplifiers and no noise at all. My unit has been sent to China and tested. It was reported that nothing was wrong with my unit. All measurements were withing the normal, and has been listened on different headphones without any hiss/humm noises.Very strange. I have checked my amp a lot with different headphones, sources and in  different places. I have asked to send me a new unit with extensive check and listening in China shop before to ship it to New Zealand. Also have made agreement with NZ distributor to check it at arrival in the shop with my headphones before pick up. Still waiting from 27July 2020. Regards, Kim


----------



## wishbon3

kimdeug said:


> Good to know.
> Is it any hissing/ humming noise? I have done intensive test with my one on Page 16-20. My USB signal was cleaned by Ifi USB 3.0 isolator. On top of this I have used power filters, DC blocker and Highly shielded power cables and RCA/ XLR shielded cables too. And have got  around 20dB humm/hissing noise. For control I have plugged to my other different headphone amplifiers and no noise at all. My unit has been sent to China and tested. It was reported that nothing was wrong with my unit. All measurements were withing the normal, and has been listened on different headphones without any hiss/humm noises.Very strange. I have checked my amp a lot with different headphones, sources and in  different places. I have asked to send me a new unit with extensive check and listening in China shop before to ship it to New Zealand. Also have made agreement with NZ distributor to check it at arrival in the shop with my headphones before pick up. Still waiting from 27July 2020. Regards, Kim




It is basically silent at this point, the only noise I had before was from the DAC itself. If I unplugged the dac from the amp, there was absolutely 0 noise from the cayin.

Do you still have buzzing when the amp is completely free from any source?


----------



## kimdeug (Dec 12, 2020)

wishbon3 said:


> It is basically silent at this point, the only noise I had before was from the DAC itself. If I unplugged the dac from the amp, there was absolutely 0 noise from the cayin.
> 
> Do you still have buzzing when the amp is completely free from any source?


Yes. I had hiss/humm noise when unplugged. If I connect any source(DAC) the hiss/humm becomes even lauder. I have done this test before, look page 16 of this forum - at the bottom.. And right after this test (27 July) I have sent it back to the dealer shop to fix it or replace. Utill now  I am waiting, and don't have the amplifier on hand.


----------



## wishbon3

kimdeug said:


> Yes. I had hiss/humm noise when unplugged. If I connect any source(DAC) the hiss/humm becomes even lauder. I have done this test before, look page 16 of this forum - at the bottom.. And right after this test (27 July) I have sent it back to the dealer shop to fix it or replace. Utill now  I am waiting, and don't have the amplifier on hand.



Yea.. Mine isn't bad at all.

One thing I noticed though, at least with the d90 dac I had previously, is the lcd display on the dac caused noise which had me replace it with something else.

Not sure why you can't turn off the display in most dacs, as it may interfere with some amps like it did in this instance.

Hope your amp is pristine in sound when you get it back brother!


----------



## Fatdoi (Dec 12, 2020)

kimdeug said:


> Yes. I had hiss/humm noise when unplugged. If I connect any source(DAC) the hiss/humm becomes even lauder. I have done this test before, look page 16 of this forum - at the bottom.. And right after this test (27 July) I have sent it back to the dealer shop to fix it or replace. Utill now  I am waiting, and don't have the amplifier on hand.


I wonder if China 220V v AU/NZ 240V makes a difference? sometimes my APC unit measures 245-248V


----------



## ThanatosVI (Dec 13, 2020)

Fatdoi said:


> I wonder if China 220V v AU/NZ 240V makes a difference? sometimes my APC unit measures 245-248V


Usually these numbers mean +/- 10% variance. In germany we have 230V which means anything between 207 - 253V. I guess it's similar for other countries. 

The device itself is likely to get damaged if it is designed for 220V and constantly run at 245-248V. Even if devices usually surive differences of +/- 15% for short periods


----------



## Fatdoi

ThanatosVI said:


> Usually these numbers mean +/- 10% variance. In germany we have 230V which means anything between 207 - 253V. I guess it's similar for other countries.
> 
> The device itself is likely to get damaged if it is designed for 220V and constantly run at 245-248V. Even if devices usually surive differences of +/- 15% for short periods


on Cayin website, the rear picture of the unit printed 220V50Hz120W..... so it may not be good for AU/NZ operating environment? or unless they have a specific model for 240V


----------



## ThanatosVI

Fatdoi said:


> on Cayin website, the rear picture of the unit printed 220V50Hz120W..... so it may not be good for AU/NZ operating environment? or unless they have a specific model for 240V


They definitely have other models as well, I got the 230V 50Hz140W Version.
So I guess they also have a 240V Version, best to ask the official distributor.

This is a thing to keep in mind when buying used tho


----------



## Fatdoi

ThanatosVI said:


> They definitely have other models as well, I got the 230V 50Hz140W Version.
> So I guess they also have a 240V Version, best to ask the official distributor.
> 
> This is a thing to keep in mind when buying used tho


thanks i'll definitely ask on this issue....


----------



## Gr3g277 (Dec 14, 2020)

ThanatosVI said:


> Usually these numbers mean +/- 10% variance. In germany we have 230V which means anything between 207 - 253V. I guess it's similar for other countries.
> 
> The device itself is likely to get damaged if it is designed for 220V and constantly run at 245-248V. Even if devices usually surive differences of +/- 15% for short periods



Hi friends,

If the issue with hiss is something related to the power line, like DC on the ground or noise on the lines, or juste bad electricity alltogether, the PS audio power plant should DEFINITELY solve the issue.
It regenerates and isolates completely all devices from your house power, I even think you can select what voltage and frequency you want it to output....

@ThanatosVI have you tried connecting the cayin to one regenerated outlets from your ps3 power plant , without any interconnects connected to the amp ?

If yes, does it kill the hissing ?

if you are willing to do some experiementing, I think we can confirm @kimdeug findings, that power from the wall isn't our problem here...


IMO, the issue is in the circuit, either gain, or volume pot placement, or isolation between the preamp stage maybe.

I ordered el cheapo Tube EMI shields, to see if It can make a difference, I will post If I find anything.

edit :
If using a computer as a source for your dac, the USB ground can make a loop wiht the interconnects grounds and create noise.

Some dacs are isolated, some are not, IE my bifrost 2 has no issue with USB thanks to its unison USB, my marantz hd dac1 has noise issue...

I solved all usb problems with a USB DDC reclocker, ( singxer su6 ), and feed the dacs with coax , all with very good results !!


----------



## ThanatosVI

Gr3g277 said:


> Hi friends,
> 
> If the issue with hiss is something related to the power line, like DC on the ground or noise on the lines, or juste bad electricity alltogether, the PS audio power plant should DEFINITELY solve the issue.
> It regenerates and isolates completely all devices from your house power, I even think you can select what voltage and frequency you want it to output....
> ...



I couldn't test the Cayin on the Power plant yet, because I am still waiting in my ordered Power cables (i don't have one that is long enough atm)

As soon as they arrive I will Report back. They are currently sheduled to arrive on the 24th


----------



## Gr3g277

ThanatosVI said:


> I couldn't test the Cayin on the Power plant yet, because I am still waiting in my ordered Power cables (i don't have one that is long enough atm)
> 
> As soon as they arrive I will Report back. They are currently sheduled to arrive on the 24th



That will be for a nice christmas gift !!!

let's hope that it will be the answer !


----------



## ThanatosVI

Gr3g277 said:


> That will be for a nice christmas gift !!!
> 
> let's hope that it will be the answer !


It would indeed be nice


----------



## wishbon3

There is slight hiss from amp of about 10 db on low gain and about 13 on high when using zmf. But it is very quiet and not much of a bother to me.

I am getting some new tubes today to see what that does, but either way I'm fine with the slight white noise.


----------



## Gr3g277

wishbon3 said:


> There is slight hiss from amp of about 10 db on low gain and about 13 on high when using zmf. But it is very quiet and not much of a bother to me.
> 
> I am getting some new tubes today to see what that does, but either way I'm fine with the slight white noise.



good for you then ! the pairing must be very good !

have you tried the zmf with a balanced headphone cable as well ?

with mine, it is noticeably higher with balanced cable.


----------



## wishbon3

Gr3g277 said:


> good for you then ! the pairing must be very good !
> 
> have you tried the zmf with a balanced headphone cable as well ?
> 
> with mine, it is noticeably higher with balanced cable.


It is about the same on both. The Dac isn't an issue, as it's the same when unplugged.

Really no big deal. It's very quiet.


----------



## kimdeug

Gr3g277 said:


> Hi friends,
> 
> If the issue with hiss is something related to the power line, like DC on the ground or noise on the lines, or juste bad electricity alltogether, the PS audio power plant should DEFINITELY solve the issue.
> It regenerates and isolates completely all devices from your house power, I even think you can select what voltage and frequency you want it to output....
> ...



I've got an email from my local distributor that my unit will arrive this Friday, max Monday. 
We are agreed to do listening test in the shop, using my and shops headphones for hiss/humm noise.
If  I am not satisfied - refund immediately in the shop.
It should be another (new) unit, 
Using all my 15 headphones amplifiers, I really missed the Cayin HA-6A sound.
None of them can do this magic with Sennheiser headphones.
Finger cross...
Also have an offer of ZMF Verite Closed Monkey wood ( new, open box) for 2200 USD
Is that worth it? Any suggestions? I am more was looking for Focal utopia.
Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> I've got an email from my local distributor that my unit will arrive this Friday, max Monday.
> We are agreed to do listening test in the shop, using my and shops headphones for hiss/humm noise.
> If  I am not satisfied - refund immediately in the shop.
> It should be another (new) unit,
> ...


Best of luck, that your new unit is free from noise.
If you still encounter noise pay extra attention to the channel. This could also be from the tubes (maybe the Shop has other tubes to try im that case)

I really hope that it will turn out well for you, since the sound of this amp is stunning


----------



## wishbon3

kimdeug said:


> I've got an email from my local distributor that my unit will arrive this Friday, max Monday.
> We are agreed to do listening test in the shop, using my and shops headphones for hiss/humm noise.
> If  I am not satisfied - refund immediately in the shop.
> It should be another (new) unit,
> ...


There is noise in mine too, but it is not as bad as I thought it would be when initially reading this thread. 

Let us know if you get rid of it completely!


----------



## Fatdoi

kimdeug said:


> I've got an email from my local distributor that my unit will arrive this Friday, max Monday.
> We are agreed to do listening test in the shop, using my and shops headphones for hiss/humm noise.
> If  I am not satisfied - refund immediately in the shop.
> It should be another (new) unit,
> ...


good luck with your testing..... my decision hinges on your outcome.... just kidding, i've just spent the amp money on Verite Ironwood.. will need to tighten up next months if the result of your fixed amp comes out good

btw can you check on the back of your amp if the power connection is labelled 240V?


----------



## Andykong (Jul 16, 2022)

Gr3g277 said:


> Spoiler
> 
> 
> 
> ...



One of the biggest different between Solid-state and Vacuum tube amplifier is that you must not listen to the tube amplifier with unconnected input. I described this as “Open-loop” condition.  I have shared my understanding on this subject previously (*HERE*) so I don't repeat myself here.



Gr3g277 said:


> IMO, the issue is in the circuit, either gain, or volume pot placement, or isolation between the preamp stage maybe.
> 
> 
> 
> ...



One of the biggest different between Solid-state and Vacuum tube amplification circuit is gain ratio.  You can adjusting the gain ratio in SS amp, or even offer a high/mid/low gain control to SS amp. users, but you won't find gain control in tube amplifier, not that I am aware of so far.  So IMHO, the quickest way to reduce noise from HA-6A is to reduce the power output.


----------



## Gr3g277

Andykong said:


> One of the biggest different between Solid-state and Vacuum tube amplifier is that you must not listen to the tube amplifier with unconnected input. I described this as “Open-loop” condition.  I have shared my understanding on this subject previously (HERE) so I don't repeat myself here.
> 
> true that, so test with the dac connected then...
> 
> One of the biggest different between Solid-state and Vacuum tube amplification circuit is gain ratio.  You can adjusting the gain ratio in SS amp, or even offer a high/mid/low gain control to SS amp. users, but you won't find gain control in tube amplifier, not that I am aware of so far.  So IMHO, the quickest way to reduce noise from HA-6A is to reduce the power output.



It is indeed not a common thing in hifi world, but all guitar tube amps in the world has a gain control... together with tone stack etc...and several gain stages
HA 6A has the volume pot before the preamp stage, should be possible to add another pot between the preamp stage and power stage, so the first pot in signal path becomes the gain control, the second becomes the master volume. I have not tried it myself so not sure it is a good solution for a headphone amp, and if it will degrade the sound quality. I am only expressing theoretical ideas for the discussion 

I Have seen amps using a NFB loop for gain control as well,IE the manley absolute.
Line magnetic 845 speaker amps use something similar as well

just to be clear, i am not implying the ha 6a, has something wrong in it's design, It is a marvellous amp with amazing sound capabilites and lots of power.
Juste wondering if some minor tweaks would enable it to be used with very sensitve headphones


----------



## skylinekursk

Just quick question about tube rolling.. It's written EL34 can be replaced by 6L6GC. What about 6L6 or 6L6G ect? Sorry for stupid question but I'm not so familiar with tube specs... Thanks!


----------



## ThanatosVI

skylinekursk said:


> Just quick question about tube rolling.. It's written EL34 can be replaced by 6L6GC. What about 6L6 or 6L6G ect? Sorry for stupid question but I'm not so familiar with tube specs... Thanks!


To my understanding the mentioned tubes all belong to the 6L6/5881 tube family and are all save to use.

To make absolutely sure I'd ask Cayin  Support to confirm this


----------



## skylinekursk

ThanatosVI said:


> To my understanding the mentioned tubes all belong to the 6L6/5881 tube family and are all save to use.
> 
> To make absolutely sure I'd ask Cayin  Support to confirm this


the only one form to fill I found on en.Cayin.cn is on Chinese... does someone knows way to reach support team? Thanks!


----------



## ThanatosVI

skylinekursk said:


> the only one form to fill I found on en.Cayin.cn is on Chinese... does someone knows way to reach support team? Thanks!


Here would be the contact data from one official russian distributor:
*Distributor
XChesser Audio*
Address：Moscow, Karamyshevskaya nab. 2k4
http://xchesser.ru
Email: order@xchesser.ru
Phone: +7 926 084-72-84

Since it is just a question the german distributors are probably also happy to help:
info@cayin.com


----------



## kimdeug

skylinekursk said:


> Just quick question about tube rolling.. It's written EL34 can be replaced by 6L6GC. What about 6L6 or 6L6G ect? Sorry for stupid question but I'm not so familiar with tube specs... Thanks!


The KT66 dissipation has 30 Watt, when 6L6G has 23 Watt, The 6L6GS has 30 Watt too, I have one pair of Brimar 6L6G will try on EL34 mod, when my unit will arrive.


----------



## ThanatosVI

@Andykong what is the max input voltage the amp can take before clipping (on RCA and XLR)

Industry Standard is 2V and 4V for ouputs, but that doesn't necessarily mean that the amp can't take more.

I'm afraid of feeding it a hot Signal with the Rockna Wavelight and Schiit Loki.


----------



## Fatdoi

kimdeug said:


> The KT66 dissipation has 30 Watt, when 6L6G has 23 Watt, The 6L6GS has 30 Watt too, I have one pair of Brimar 6L6G will try on EL34 mod, when my unit will arrive.


have you done the testing on the 'fixed'/new amp yet?


----------



## Andykong

ThanatosVI said:


> @Andykong what is the max input voltage the amp can take before clipping (on RCA and XLR)
> 
> Industry Standard is 2V and 4V for ouputs, but that doesn't necessarily mean that the amp can't take more.
> 
> I'm afraid of feeding it a hot Signal with the Rockna Wavelight and Schiit Loki.



We have tested 3V for RCA and 6V for XLR inputs, they are fine in our measurement, we didn't go any further beyond that.  So what is the output level of Wavelight and Loki?


----------



## Andykong

skylinekursk said:


> Just quick question about tube rolling.. It's written EL34 can be replaced by 6L6GC. What about 6L6 or 6L6G ect? Sorry for stupid question but I'm not so familiar with tube specs... Thanks!



We don't recommend using 6L6 or 6L6G as EL34 substitutes on HA-6A, we are not saying that the amplifier will be damaged because of that, but the amplifier is "optimised" for a different set of parameters from these non-listed tubes, so we don't recommend them officially.



skylinekursk said:


> the only one form to fill I found on en.Cayin.cn is on Chinese... does someone knows way to reach support team? Thanks!



On Contact us page of en.cayin.cn, we have provide several email address, and  info@cayin.cn is designated for Technical Support, if you have any question, you can email them directly, they can handle English enquiries.


----------



## ThanatosVI

Andykong said:


> We have tested 3V for RCA and 6V for XLR inputs, they are fine in our measurement, we didn't go any further beyond that.  So what is the output level of Wavelight and Loki?


Wavelight has 2.4V and 5.8V
So this should be fine.

Not sure about Loki, will inquire at Schiit


----------



## kimdeug (Dec 25, 2020)

Fatdoi said:


> have you done the testing on the 'fixed'/new amp yet?


Dear Headphone and HA-6A Lovers.

I can proudly announce now, that my unit has arrived to New Zealand.
Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
There is a tiny hiss left at the high impedance (Low and med impedance - no hiss at all on both XLR and 1/4 output)
But I absolutely can accept it. No humm noise too.
Compare what it was before, now the hiss is hardly noticeable on Sennheiser HD800S and ZMF Auteur.
Roughly, I can say the hiss is 10 times less than what was before, hardly noticeable and does not affect the music listening experience now.
Please, take it into account that the replaced/new unit was hand-picked and intensively tested before to send it to NZ.
As result, it came with JJ tubes instead of Electro-Harmonics 12AU7.
But waiting time and result was absolutely worth it.
Want to give a Big Thanks to Andykong and John from Cayin team for support, NZ distributer Deano from Rapallo shop and all you guys to make it happens.
I think, this is the endgame amplifier for me (unless something better will come).
Time to do the tube rolling now.
Any suggestions?

And Merry Christmas from New Zealand!!!!!!!

Regards,
Kim


----------



## skylinekursk (Dec 25, 2020)

kimdeug said:


> Dear Headphone and HA-6A Lovers.
> 
> I can proudly announce now, that my unit has arrived to New Zealand.
> Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
> ...


Great to read amp arrived... finally!!! I wish you best experience with cayin ha6a because it can be great sounding amp!!!
Please share tube rolling results with us!
I ordered sylvania 12au7 and looking for EL34 replacement because with my new headphones it’s sounds better than kt88.
Hiss is noticeable on high gain and after 3 hours on volume selector but this with music playing can blow my headphones))


----------



## Andykong

kimdeug said:


> Dear Headphone and HA-6A Lovers.
> 
> I can proudly announce now, that my unit has arrived to New Zealand.
> Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
> ...


Glad to know the new HA-6A unit arrive in good shape, I hope you can enjoy your music peaceful from here on.   

Our side of the story: we couldn't find any problem on the unit send to us from Australia dealer, but we send a new unit back to Australia just in case, there is no point to send the original unit back to our customer when it has been shipped back and forth and travelled around the southern hemisphere already.  We have, based on the complaint from Kim, focused on several potential source of noise, and we finally decided to change the stock driver tube to JJ as Kim has mentioned.  We have updated our product line and inventory, replacing the driver tube on our stock units immediately. From this point onward, all HA-6A will be shipped from Cayin with JJ ecc82 instead of EH 12AU7.


----------



## skylinekursk (Dec 25, 2020)

Andykong said:


> Glad to know the new HA-6A unit arrive in good shape, I hope you can enjoy your music peaceful from here on.
> 
> Our side of the story: we couldn't find any problem on the unit send to us from Australia dealer, but we send a new unit back to Australia just in case, there is no point to send the original unit back to our customer when it has been shipped back and forth and travelled around the southern hemisphere already.  We have, based on the complaint from Kim, focused on several potential source of noise, and we finally decided to change the stock driver tube to JJ as Kim has mentioned.  We have updated our product line and inventory, replacing the driver tube on our stock units immediately. From this point onward, all HA-6A will be shipped from Cayin with JJ ecc82 instead of EH 12AU7.


Good to know that, thanks! I waiting for NOS sylvania 12au7!


----------



## wishbon3

Could I get some of dem JJ tubes?  hehehe


----------



## ThanatosVI

kimdeug said:


> Dear Headphone and HA-6A Lovers.
> 
> I can proudly announce now, that my unit has arrived to New Zealand.
> Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
> ...



Glad it finally resolved with a satisfying result.
Now you can enjoy it like the rest of us  

Also maybe my amp already had a few improvements, because my amp pretty much sounds as what you describe about hum.



Andykong said:


> Glad to know the new HA-6A unit arrive in good shape, I hope you can enjoy your music peaceful from here on.
> 
> Our side of the story: we couldn't find any problem on the unit send to us from Australia dealer, but we send a new unit back to Australia just in case, there is no point to send the original unit back to our customer when it has been shipped back and forth and travelled around the southern hemisphere already.  We have, based on the complaint from Kim, focused on several potential source of noise, and we finally decided to change the stock driver tube to JJ as Kim has mentioned.  We have updated our product line and inventory, replacing the driver tube on our stock units immediately. From this point onward, all HA-6A will be shipped from Cayin with JJ ecc82 instead of EH 12AU7.


Interesting, what differences do ecc82 have compared to 12au7? 
Or are they simply more silent in general?

I also got a pair of PSVane 12au7 for christmas from my brother. Luckily also a dead silent pair


----------



## Newsee

kimdeug said:


> I think, this is the endgame amplifier for me (*unless something better will come*).
> Time to do the tube rolling now.


I am happy about the happy end and like that part. Carries a great amount of wisdom .



Andykong said:


> We have, based on the complaint from Kim, focused on several potential source of noise, and we finally decided to change the stock driver tube to JJ as Kim has mentioned.  We have updated our product line and inventory, replacing the driver tube on our stock units immediately. From this point onward, all HA-6A will be shipped from Cayin with JJ ecc82 instead of EH 12AU7.


It is amazing to see that customer complaints are taken so seriously that it results in a product change. Hats off!


----------



## Marutks

All this trouble because of a noisy tube?     It would be the first thing that comes to mind.   Try some NOS tubes.


----------



## Relaxasaurus

kimdeug said:


> Dear Headphone and HA-6A Lovers.
> 
> I can proudly announce now, that my unit has arrived to New Zealand.
> Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
> ...





Andykong said:


> From this point onward, all HA-6A will be shipped from Cayin with JJ ecc82 instead of EH 12AU7.



Merry Christmas and glad you got your amp @kimdeug ! Thanks for the info Andy, purchasing a matched pair of JJ Tubes as we speak... Cheers all!


----------



## kimdeug (Jan 3, 2021)

Marutks said:


> All this trouble because of a noisy tube?     It would be the first thing that comes to mind.   Try some NOS tubes.


I Think, apart of new JJ ECC82 tubes there are few changes in the circuits too. 
Also, I think there is a slight reduction of gain, compare with my first unit. Hard to tell exactly, but from my feeling the new unit has little bit less volume than before.
Regarding to the tubes. I have tried all combination CEG KT88, RCA 6550, Svetlana etc, Drivers tubes 12AU7/ ECC82/ ECC802S: Electro Harmonics gold pins, Genalex Gold Lion 12AU7, Siemens ECC82, Tesla 802S, Sylvania and few more tubes.
All of them have been tested on old unit with hiss/humm issues. 
Now looking for nice driver tubes as the power tubes range is quite limited.

Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> I Think, apart of new JJ ECC82 tubes there are few changes in the circuits too.
> Also, I think there is a slight reduction of gain, compare with my first unit. Hard to tell exactly, but from my feeling the new unit has little bit less volume than before.
> Regarding to the tubes. I have tried all combination CEG KT88, RCA 6550, Svetlana etc, Drivers tubes 12AU7/ ECC82/ ECC802S: Electro Harmonics gold pins, Genalex Gold Lion 12AU7, Siemens ECC82, Tesla 802S, Sylvania and few more tubes.
> All of them has been tested on old unit with hiss/humm issues.
> ...


How did the Gold Lion 12au7 sound compared to the electro harmonix?


----------



## kimdeug

ThanatosVI said:


> How did the Gold Lion 12au7 sound compared to the electro harmonix?


It is hard to say by memory now. Because at that time I was more concentrated on hiss/ humm sound. And they were not my tubes. Now, I have already ordered 5 different pairs of 12AU7 tubes (Gold lion included), will post my impressions later, then arrived. Regards, Kim


----------



## ThanatosVI

kimdeug said:


> It is hard to say by memory now. Because at that time I was more concentrated on hiss/ humm sound. And they were not my tubes. Now, I have already ordered 5 different pairs of 12AU7 tubes (Gold lion included), will post my impressions later, then arrived. Regards, Kim


Very much appriciated. 
Until now I only have EH gold pin and PSVane 12au7. 
More to follow


----------



## Fatdoi

kimdeug said:


> Dear Headphone and HA-6A Lovers.
> 
> I can proudly announce now, that my unit has arrived to New Zealand.
> Have been done intensive test in the dealer shop and at my home studio facilities with different headphones, signal sources and power filtering.
> ...



Congrats on finally getting the amp you're happy with....


----------



## kimdeug (Jan 3, 2021)

Relaxasaurus said:


> Merry Christmas and glad you got your amp @kimdeug ! Thanks for the info Andy, purchasing a matched pair of JJ Tubes as we speak... Cheers all!


Nice video man "part 2". Have you finished your video with Cayin HA-6A vs WA22? I have a very attractive offer for WA22 last revision. What do you think? Buy or not to buy? Hard to choose. Regards, Kim


----------



## wishbon3

kimdeug said:


> Nice video man "part 2". Did you finished your video with Cayin HA-6A vs WA22? I have a very attractive offer for WA22 last revision. What do you think? Buy or not to buy? Hard to choose. Regards, Kim


Also interested in this answer!


----------



## ThanatosVI

wishbon3 said:


> Also interested in this answer!


We all are


----------



## Relaxasaurus

Hi folks, thanks for the support! I plan on releasing it this month. I am happy to hear that @kimdeug 's amp has the hiss issue addressed.


----------



## skylinekursk

hi guys, 
does anyone can compare lcd-x vs empyrean on ha6a?


----------



## Ryan Cao

Hello HA-6A owners! How's the hiss of the amp? Is it dead silent, or noticeable but not bothering?


----------



## skylinekursk

Ryan Cao said:


> Hello HA-6A owners! How's the hiss of the amp? Is it dead silent, or noticeable but not bothering?


It depends of headphone’s sensivity... if you have planars hiss is almost nothing on highest volume. But I can’t listen music on this volume so have no hiss issue


----------



## Ryan Cao

skylinekursk said:


> It depends of headphone’s sensivity... if you have planars hiss is almost nothing on highest volume. But I can’t listen music on this volume so have no hiss issue


How about headphones like HD800s and Focal Utopia?


----------



## wishbon3

Ryan Cao said:


> Hello HA-6A owners! How's the hiss of the amp? Is it dead silent, or noticeable but not bothering?


The hiss is there, but it's a faint white noise and does not interfere with music.

Different 12au7 tubes raise or lower the hiss, so getting the right ones are paramount IMO. Apparently the JJs are the best, but I haven't tried them yet.


I use ZMF HPs, and there's definitely a faint hiss.

I get my HD 800s this week, I'll report back on those.


----------



## Relaxasaurus

skylinekursk said:


> hi guys,
> does anyone can compare lcd-x vs empyrean on ha6a?


I had both at some point with the HA-6A, the Empyrean more recently. I absolutely love the Empy and it mates nicely with the HA-6A. Tons of power from the Cayin to drive them and the euphonic qualities of the amp brought out more enjoyment for me.

The LCD-X worked better with solid state comparatively. It's not quite as resolving as the Meze and I personally liked it better with something clean & powerful like a V280. It didn't sound bad with the HA-6A, I just preferred pairing the Empyreans more with it.


----------



## ThanatosVI

Relaxasaurus said:


> I had both at some point with the HA-6A, the Empyrean more recently. I absolutely love the Empy and it mates nicely with the HA-6A. Tons of power from the Cayin to drive them and the euphonic qualities of the amp brought out more enjoyment for me.
> 
> The LCD-X worked better with solid state comparatively. It's not quite as resolving as the Meze and I personally liked it better with something clean & powerful like a V280. It didn't sound bad with the HA-6A, I just preferred pairing the Empyreans more with it.


Empyrean and HA-6A is a wonderful combination


----------



## skylinekursk

Thank you gentlemen! 
I had Empyrean and ha6a, then I sold empy because I needed cash... it wassynergy between those two! I also had lcd-x year ago but with another amp!
Now I’m looking for detailed HP with engaging and punchy sound... I know LCD4 is not an ideal in this case... maybe I need looking for Diana v2??


----------



## kimdeug

Ryan Cao said:


> How about headphones like HD800s and Focal Utopia?


Read this forum from page 15 and you will find all the answers there)


----------



## kimdeug

wishbon3 said:


> The hiss is there, but it's a faint white noise and does not interfere with music.
> 
> Different 12au7 tubes raise or lower the hiss, so getting the right ones are paramount IMO. Apparently the JJs are the best, but I haven't tried them yet.
> 
> ...


I think you are absolutely correct.
The hiss now (on new unit)  is acceptable. 
Lets say, this is the normal tube operation hiss/background noise.
Now the challenge is to find the quietest 12AU7/ E82CC/ECC82/ECC802S/ CV4003 tubes.

Please, share your findings here.
Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> I think you are absolutely correct.
> The hiss now (on new unit)  is acceptable.
> Lets say, this is the normal tube operation hiss/background noise.
> Now the challenge is to find the quietest 12AU7/ E82CC/ECC82/ECC802S/ CV4003 tubes.
> ...


I have some 12au7 EH gold and PSVane both really silent. I also recommend to always mention that you want especially silent tubes on checkout. Many reputeable tube sellers react on that.


----------



## wishbon3

ThanatosVI said:


> I have some 12au7 EH gold and PSVane both really silent. I also recommend to always mention that you want especially silent tubes on checkout. Many reputeable tube sellers react on that.


I did not like PSVane as the hiss wasn't that great.

The best so far for me have been some cleartop RCA's. If the JJs can beat them, they will be perfect.


----------



## kimdeug

wishbon3 said:


> I did not like PSVane as the hiss wasn't that great.
> 
> The best so far for me have been some cleartop RCA's. If the JJs can beat them, they will be perfect.


I am very sceptical to Chinese tubes, as PSVan, Shungan, Gold Voice etc.

Prefer NOS US, German, Holland, UK tubes
Very positive to Tesla old stock tubes
New Russian tubes like Electroharmonics, Genalex gold lion, Tung Sol, Mullard are come from the same factory.

Regards, 
Kim


----------



## skylinekursk

would you guys help me? I consider 18 Ohm planar headphones with 80 dB sensitivity...I'm guess there is no chance for ha6a to power HP?


----------



## Fatdoi

skylinekursk said:


> would you guys help me? I consider 18 Ohm planar headphones with 80 dB sensitivity...I'm guess there is no chance for ha6a to power HP?


think this specs best to use SS amps


----------



## skylinekursk

Fatdoi said:


> think this specs best to use SS amps


Just checked email and there is answer from German distributor - Thomas:

The HA-6A will easily drive the planar headphones which has 18 ohm impedance and 77 db sensitivity.

Best regards

Thomas


----------



## ThanatosVI

@Andykong can the Ha-6a be used as a preamp?
There is an amp from T+A which has a simple 4 pin XLR to RCA cable, and can be connected that way as preamp for a Power amp. So from regular 4 pin XLR headphone out to RCA input on the Power amp.

I wonder of that is something that generally works, or if that would risk damage to the Ha-6a 

Also the official Power specs for headphones,  into which load are those?
32 Ohm by any Chance?


----------



## Andykong (Jan 8, 2021)

ThanatosVI said:


> @Andykong can the Ha-6a be used as a preamp?
> There is an amp from T+A which has a simple 4 pin XLR to RCA cable, and can be connected that way as preamp for a Power amp. So from regular 4 pin XLR headphone out to RCA input on the Power amp.
> 
> I wonder of that is something that generally works, or if that would risk damage to the Ha-6a
> ...



HA-6A cannot serve as Preamp because there is no RCA or XLR output connectors on the back panel, only inputs.

The output ratings in HA-6A specification have stated that the EL34 6.35mm phone out in Triode mode Low impedance setting is 750 mW per channel, and KT88 XLR4 or 4.4mm phone out in Ultralinear mode Low impedance setting is 1900mW per channel.  This is transformer coupled design, and the output is determined by the impedance setting of amplifier, which in term connect to a specific output terminals from the output transformers, so when you switch the impedance setting to L, it doesn't matters whether you are connecting a 16 Ohm or a 300 Ohm headphone to the amplifier, the output doesn't change significantly.


----------



## ThanatosVI (Jan 8, 2021)

Andykong said:


> HA-6A cannot serve as Preamp because there is no RCA or XLR output connectors on the back panel, only inputs.
> 
> The output ratings in HA-6A specification have pretty much cover every combination already , so EL34 6.35mm phone out in Triode mode Low impedance setting is 750 mW per channel, and KT88 XLR4 or 4.4mm phone out in Ultralinear mode High impedance setting is 4500mW per channel. IF there is any combination that is not listed in the table, I can ask our engineers to take a measurement later.


I know it has no preamp outs,  That's why I described the "weird" connection from headphone XLR out on the front to power amp RCA in, with a special cable. (4-PIN XLR male to RCA)
It works for at least one Headphone amp I know of (T+A Ha200), but wanted to ask if this would also work for the Cayin or be dangerous and could damage it.

Regarding the power, the info into which load is missing.
So the settings UL + High + XLR out on KT88s can output 4.5W - however we don't know into which headphone load.
It's hard to Imagine that the output power doesn't change much with load,  at least for the higher examples. 
Let's take an Audeze LCD4 200 ohm and use KT88 - UL - High setting.
That would mean 4.5W but in 200 Ohm, That's 100W in 8 ohm speaker amp level.


----------



## Andykong

ThanatosVI said:


> I know it has no preamp outs,  That's why I described the "weird" connection from headphone XLR out on the front to power amp RCA in, with a special cable. (4-PIN XLR male to RCA)
> It works for at least one Headphone amp I know of (T+A Ha200), but wanted to ask if this would also work for the Cayin or be dangerous and could damage it.
> 
> Regarding the power, the info into which load is missing.
> ...



We don't recommend that because a proper line out connection will include GND signal, but the XLR4 to RCA does not have the ground signal, I assume you are using the negative phase as GND in your XLR4 to RCA cable?  This might introduce ground loop due to significant different in ground level, and there is no way to predict whether the ground loop will be audible, if it works, its good luck.  If it don't work, you might endanger your complete system because improper grounding.

4.5W but 200 Ohm might be equal to 100W in 8 ohm speaker amp level THEORETICALLY in Solid State amplification, but not the case with Transformer Coupled Tube amplifier. For your assumption to work, the output rating should doubled when you lower the impedance by half, and when you double the impedance, the output rating will be reduced by half.   Take a close look at the output numbers and you'll notice the trends goes exactly the other way.


----------



## skylinekursk (Jan 9, 2021)

Andykong said:


> We don't recommend that because a proper line out connection will include GND signal, but the XLR4 to RCA does not have the ground signal, I assume you are using the negative phase as GND in your XLR4 to RCA cable?  This might introduce ground loop due to significant different in ground level, and there is no way to predict whether the ground loop will be audible, if it works, its good luck.  If it don't work, you might endanger your complete system because improper grounding.
> 
> 4.5W but 200 Ohm might be equal to 100W in 8 ohm speaker amp level THEORETICALLY in Solid State amplification, but not the case with Transformer Coupled Tube amplifier. For your assumption to work, the output rating should doubled when you lower the impedance by half, and when you double the impedance, the output rating will be reduced by half.   Take a close look at the output numbers and you'll notice the trends goes exactly the other way.


Thanks for information but I don’t understand what power output will be for 18 ohm 77 db phones? I guess it will lower than lowest number in specs? I’m asking because these phones are little bit more «hungry» than he6..... and for he6 it’s need 5 wt at 50 ohm

I’m using now 30 ohm planar phones with 97 db and use volume at 11-13 clocks depends on track. Switching gain selector not much changes but just volume a little bit... so I really don’t understand...


----------



## Andykong

skylinekursk said:


> Thanks for information but I don’t understand what power output will be for 18 ohm 77 db phones? I guess it will lower than lowest number in specs? I’m asking because these phones are little bit more «hungry» than he6..... and for he6 it’s need 5 wt at 50 ohm
> 
> I’m using now 30 ohm planar phones with 97 db and use volume at 11-13 clocks depends on track. Switching gain selector not much changes but just volume a little bit... so I really don’t understand...



To be honest, your extremely hungry low-impedance planar headphone is a very marginal case, I am reluctant to comment before I give it a try.  Its not about voltage, its about current.  HA-6A have enough voltage output to make it play extremely loud, but I have no idea how much current it will draw at 17ohm.  There is no way to predict the audio performance without hearing them in action.


----------



## skylinekursk

Andykong said:


> To be honest, your extremely hungry low-impedance planar headphone is a very marginal case, I am reluctant to comment before I give it a try.  Its not about voltage, its about current.  HA-6A have enough voltage output to make it play extremely loud, but I have no idea how much current it will draw at 17ohm.  There is no way to predict the audio performance without hearing them in action.



anyway thanks for your comment! I appreciate this!


----------



## ThanatosVI

Andykong said:


> We don't recommend that because a proper line out connection will include GND signal, but the XLR4 to RCA does not have the ground signal, I assume you are using the negative phase as GND in your XLR4 to RCA cable?  This might introduce ground loop due to significant different in ground level, and there is no way to predict whether the ground loop will be audible, if it works, its good luck.  If it don't work, you might endanger your complete system because improper grounding.
> 
> 4.5W but 200 Ohm might be equal to 100W in 8 ohm speaker amp level THEORETICALLY in Solid State amplification, but not the case with Transformer Coupled Tube amplifier. For your assumption to work, the output rating should doubled when you lower the impedance by half, and when you double the impedance, the output rating will be reduced by half.   Take a close look at the output numbers and you'll notice the trends goes exactly the other way.


Thank you for the clarifications, especially on the ground loop


----------



## ThanatosVI (Jan 12, 2021)

The wife gifted me a pair of Gold Lion KT77s

Can't wait to test them


----------



## skylinekursk

Hi, guys! 
Just quick update... tried those "heavy" headphones Myst Ortophones on my HA-6A and it performed very impressive. I think abyss1266, he6, lcd4 is not problem for amp...
2 NOS 12au7 Sylvania's arrived and be tested on weekend... 

Just wondering...is it possible to connect 2 pair of HP (xlr+se) and just switch between during amp work?


----------



## ThanatosVI

skylinekursk said:


> Hi, guys!
> Just quick update... tried those "heavy" headphones Myst Ortophones on my HA-6A and it performed very impressive. I think abyss1266, he6, lcd4 is not problem for amp...
> 2 NOS 12au7 Sylvania's arrived and be tested on weekend...
> 
> Just wondering...is it possible to connect 2 pair of HP (xlr+se) and just switch between during amp work?


Never heard of those HPs before, they are definitely nice to look at.

And yes you can connect several headphones at once and then switch via the front selector


----------



## skylinekursk

ThanatosVI said:


> Never heard of those HPs before, they are definitely nice to look at.
> 
> And yes you can connect several headphones at once and then switch via the front selector



I have 2 models of this Russian brand... first one is isodynamic headphones and second one is ortodynamic.... sounds different but both are very good with Cayin HA-6A....
Newer version and design.... you can see how driver looks like


----------



## ThanatosVI

skylinekursk said:


> I have 2 models of this Russian brand... first one is isodynamic headphones and second one is ortodynamic.... sounds different but both are very good with Cayin HA-6A....
> Newer version and design.... you can see how driver looks like


Looks strongly inspired by older Hifiman headphones from the design


----------



## ThanatosVI

@Andykong can you tell us the output impedance of the 3 impedance settings (or ask the engineers)

The spec sheet tells us for which load impedance the settings are intended but not which impedance the output has on each setting.


----------



## Andykong

ThanatosVI said:


> @Andykong can you tell us the output impedance of the 3 impedance settings (or ask the engineers)
> 
> The spec sheet tells us for which load impedance the settings are intended but not which impedance the output has on each setting.



We don't know the figure, and we don't intend to publish the detail output impedance.


----------



## ThanatosVI

Andykong said:


> We don't know the figure, and we don't intend to publish the detail output impedance.


Sad to hear that


----------



## skylinekursk

Looks like ha6a can power any headphones...
Tried catch hizz with my “hungry” planars - dead silent


----------



## skylinekursk

how about kt120 and kt150 as replacement for kt66?


----------



## ThanatosVI (Jan 18, 2021)

skylinekursk said:


> how about kt120 and kt150 as replacement for kt66?


Cayin Ha-6a can't power KT120 and KT150 as they draw more plate current.

If I had to Name a downside of this amp, this would be it!

If they ever upgrade the amp to be able to Support this, I'd send mine in for the upgrade


----------



## Gr3g277

skylinekursk said:


> how about kt120 and kt150 as replacement for kt66?


hello my friend,

For KT KT120 and 150 I don't think they will be compatible, because the heater current needed is higher than kt88 (1.9A vs 1.6A), and it will put more effort in the power transformer.
that can result in more heat generated as well as transformer core saturation.

Unless @Andykong says the transformer has enough margin to take it, I would'nt try.

For KT 66, they should be compatible,because heater current is lower (1.3A) but, they have only a 25w dissipation rating in comparison to the 42w rating of kt 88.
depending on the operating voltages and Bias , they could run too hot if you let the rear switch in Kt88 mode. You can try with the switch on the EL34 setting to be safe, and see how that sounds.

In the official documentation, kt66 is stated to be compatible in el34mode :






KT66 is a beautifully linear tube, results should be good. I haven't tried it yet, but I would like to hear from you if you do try them !

for power tubes i tried kt88, el34, 6ca7,6l6gc, kt77
personnaly, I like 6l6gc best for my utopias, and el34 best for my planar hifiman arya

in general i find kt88 to be hifi , almost solid state like with great bass and details,lacks a bit in refinement, and el34 more romantic and refined with emphasize on mids and rounder sound, good soundstage.
kt77 are like el 34 but with more highs and lows, but a bit unrefined.
6l6gc are very lush with good balance and nice details and nice soundstage
6ca7 where a bright and very detailled, refined, and pleasant but only lasted about 2 months ( don't know if they were faulty to begin with or if the amp run them too hot )

if you try kt66, I will wait for your impressions !


----------



## skylinekursk

Gr3g277 said:


> hello my friend,
> 
> For KT KT120 and 150 I don't think they will be compatible, because the heater current needed is higher than kt88 (1.9A vs 1.6A), and it will put more effort in the power transformer.
> that can result in more heat generated as well as transformer core saturation.
> ...



Thank You for such detailed reply!
I have to say I consider new tubes made in russia instead of NOS because it's here)))... just rolled 12au7 from Sylvania but not so much difference I'd say... I changed HP so that could be reason! 
About power tubes... kt88 and 6f8g (on my DAC) made sound more timbre and good soundstage. This is my choice for today...
I liked el34 and I'm looking on more lush sound with more harmonics but with more details than EHX EL34.. idea to switch between 2 worlds... kt88 like SS amp and something really warm and lush... what it's gonna be? 
I went back and forth with tube seller...he suggested kt120 and kt150 but it's not an option anymore... kt66 is drier than kt88 he said (?)... so I might look on el34 from Mullard? He seel tung-sol, genalex, Mullard, soviet, Svetlana, electro harmonix.... kinda a mess.. 
Thanks!!
Nik


----------



## ThanatosVI

skylinekursk said:


> Thank You for such detailed reply!
> I have to say I consider new tubes made in russia instead of NOS because it's here)))... just rolled 12au7 from Sylvania but not so much difference I'd say... I changed HP so that could be reason!
> About power tubes... kt88 and 6f8g (on my DAC) made sound more timbre and good soundstage. This is my choice for today...
> I liked el34 and I'm looking on more lush sound with more harmonics but with more details than EHX EL34.. idea to switch between 2 worlds... kt88 like SS amp and something really warm and lush... what it's gonna be?
> ...


If you search for something in between KT88 and EL34, I recommend the Gold Lion KT77. 

If it had more Extension it would be perfect. They are quite cheap, so testing them can't hurt.

However I'm also interested to hear warm and lush tubes, especially in the preamp section. (Current production units)


----------



## Gr3g277

skylinekursk said:


> Thank You for such detailed reply!
> I have to say I consider new tubes made in russia instead of NOS because it's here)))... just rolled 12au7 from Sylvania but not so much difference I'd say... I changed HP so that could be reason!
> About power tubes... kt88 and 6f8g (on my DAC) made sound more timbre and good soundstage. This is my choice for today...
> I liked el34 and I'm looking on more lush sound with more harmonics but with more details than EHX EL34.. idea to switch between 2 worlds... kt88 like SS amp and something really warm and lush... what it's gonna be?
> ...



My friend, 

You want the 6l6wgc blackplates
Those are the ones I personnaly prefer, they have spent the most of time in my ha 6a...
https://www.tubeampdoctor.com/en/6l6wgc-str-blackplate-ge-style-tad-premium-matched?number=RT812

Or from your russian seller, try to get tung sol 5881.

I have yet to try the 6550 as well
They are the go to in bass amps...


----------



## ThanatosVI

Gr3g277 said:


> My friend,
> 
> You want the 6l6wgc blackplates
> Those are the ones I personnaly prefer, they have spent the most of time in my ha 6a...
> ...


And the TAD KT88-STR Blackplates. Those have actually the superior bass compared to the 6550


----------



## Gr3g277

ThanatosVI said:


> And the TAD KT88-STR Blackplates. Those have actually the superior bass compared to the 6550



Have you heard them in the ha 6a ? I was evaluating between the 6550 and kt88 blackplates for my next try....

I have too much tubes XD
It is going out of hand.....


----------



## ThanatosVI

Gr3g277 said:


> Have you heard them in the ha 6a ? I was evaluating between the 6550 and kt88 blackplates for my next try....
> 
> I have too much tubes XD
> It is going out of hand.....


Not yet, but a Review on tubeampdoctor.com compared them to each other

Next up are the EAT KT88.
Then maybe the KR KT88 and after that the TAD KT88-STR blackplates

As you said too many.
Also want to test Gold Lion 12au7 and Mullard 12au7


----------



## kimdeug (Jan 23, 2021)

Gr3g277 said:


> hello my friend,
> 
> For KT KT120 and 150 I don't think they will be compatible, because the heater current needed is higher than kt88 (1.9A vs 1.6A), and it will put more effort in the power transformer.
> that can result in more heat generated as well as transformer core saturation.
> ...



Thanks for sharing the impression. Very informative.
This year I am going to Focal line instead of my Sennheizer HD 6XX series.
Already have Elex drop version. Love the France Quality, design and how they are treating my ears.
Focal Clear Pro, Radiance and Utopia are coming soon (already have ordered - my birthday gift to myself).
Was hunting Utopia last 3 years for a good price. (got it for 2000 USD B-Stock, brand new, replaced new drivers from official dealer).
Radiance, I have bought it just because of view to my collection - the best ever looking headphone I have seen.
So excited to listen them on Cayin HA-6A.
Due to Covid-19 the shipment to NZ is very slow (2-3 months)
Also collecting some 12AU7 tubes to roll.
Will post my tube rolling findings here, but later.

Regards from NZ
Kim[/QUOTE]


----------



## JP281 (Feb 13, 2021)

.


----------



## skylinekursk

@Andykong 
Hello! 
What is input impedance for HA6-A? 
Thanks!


----------



## rulerofrecords

ThanatosVI said:


> Not yet, but a Review on tubeampdoctor.com compared them to each other
> 
> Next up are the EAT KT88.
> Then maybe the KR KT88 and after that the TAD KT88-STR blackplates
> ...


Hi, some quick final questions regarding the buying experience with Son-audio If I may?  Did the communication with them go smoothly (I'm not comfortable communicating in French anymore), shipping experience and more importantly - warranty. Being a "European" issued amp - Cayin Germany should cover/handle warranty issues? Thanx and cheers Uli


----------



## ThanatosVI

rulerofrecords said:


> Hi, some quick final questions regarding the buying experience with Son-audio If I may?  Did the communication with them go smoothly (I'm not comfortable communicating in French anymore), shipping experience and more importantly - warranty. Being a "European" issued amp - Cayin Germany should cover/handle warranty issues? Thanx and cheers Uli


Hi Uli, 

I think that you contacted me via Audio-markt.de last week.
I must warn you, the seller does speak nothing but french, our communication Was absolute minimum and with help of Google translate.
Most of the process can be done semi Automated via the website,  shipment arrived via DHL express in less than 24h, which was impressive. However it took a while until it was sent on its way, and the communication up to the point was lacking 

The seller Was unable to answer most questions though and therefore ignored them. SO BE CAUTIOUS IF SOMETHING GOES WRONG IT MIGHT BE A HUGE HASSLE TO GET IT SORTED.

Cayins warranty restrictions suck. They only provide warranty for the First buyer and only in the country of origin.
Son-video also only offers warranty in mainland france.

So buying it from france basically means you have a new device without warranty.

When buying a used device from germany you also wont have any warranty unless the original buyer registered his device in the first 14 days


----------



## rulerofrecords

ThanatosVI said:


> Hi Uli,
> 
> I think that you contacted me via Audio-markt.de last week.
> I must warn you, the seller does speak nothing but french, our communication Was absolute minimum and with help of Google translate.
> ...


Thank you Thanato, c'est la merde! Not sure if that was me on audio-markt (what item?) - but that sounds like the whole process is a lot of fun ;-(
I just can't see how Cayin.de can decline a new Euro-amp from being covered. But I'll guess that is something that has to be experienced in the real world. I have owned two used Cayin speakers amps before and never had any issues. So knock on wood - I'll be watching my options just for a little while before making the call ...

Maybe the gentlemen from Cayin could address the warranty situation for European customers?


----------



## Andykong

rulerofrecords said:


> Thank you Thanato, c'est la merde! Not sure if that was me on audio-markt (what item?) - but that sounds like the whole process is a lot of fun ;-(
> I just can't see how Cayin.de can decline a new Euro-amp from being covered. But I'll guess that is something that has to be experienced in the real world. I have owned two used Cayin speakers amps before and never had any issues. So knock on wood - I'll be watching my options just for a little while before making the call ...
> 
> Maybe the gentlemen from Cayin could address the warranty situation for European customers?



I was not involved in the dealer appointment and liaison, so I have no idea about the terms and condition regarding sales territories and warranty coverage, so I can't offer any suggestion or opinion on this subject.  In fact, I always check out "Where to Buy" page from Cayin website for latest information of dealers in different location, that's how I keep myself update on this area, so that tells you how much I know about international dealership.  My role is mainly related to the product itself.


----------



## Andykong

*Cayin's Chinese New Year Holiday Announcement*

The Chinese New Year is around the corner, all teams in Cayin will be having their yearly holiday starting from this Sunday.

Holiday period: 7 Feb _2021 to 20 Feb 2021_

We'll resume office operation on 21 Feb 2021

All members of Cayin wish everyone an amazing Year of the Ox.


----------



## Andykong

skylinekursk said:


> @Andykong
> Hello!
> What is input impedance for HA6-A?
> Thanks!



I assume you are referring to the RCA and XLR input impedance?  Never run into customer who needed this information.  I need to come back to you after Chinese New Year break.


----------



## rulerofrecords

Andykong said:


> I was not involved in the dealer appointment and liaison, so I have no idea about the terms and condition regarding sales territories and warranty coverage, so I can't offer any suggestion or opinion on this subject.  In fact, I always check out "Where to Buy" page from Cayin website for latest information of dealers in different location, that's how I keep myself update on this area, so that tells you how much I know about international dealership.  My role is mainly related to the product itself.


fair enough, thanx anyway ...


----------



## skylinekursk

Andykong said:


> I assume you are referring to the RCA and XLR input impedance?  Never run into customer who needed this information.  I need to come back to you after Chinese New Year break.


everything happens for the first time...
making DAC based on AD1862, so need to have compatibility...


----------



## rulerofrecords

Hi, I actually did read most of the pages here - but I cannot recall finding this particular information. My question - is anybody using the EL37 with this amp and if so is that worth the effort?


----------



## ThanatosVI

rulerofrecords said:


> Hi, I actually did read most of the pages here - but I cannot recall finding this particular information. My question - is anybody using the EL37 with this amp and if so is that worth the effort?


Are you referring to thr EL34?

Those have sweeter mids but less extension on both sides.
Mid-fi guy prefers them to the KT88.

They arw by no means Bad,  as a basshead I craved the KT88 extension tho


----------



## rulerofrecords

ThanatosVI said:


> Are you referring to thr EL34?
> 
> Those have sweeter mids but less extension on both sides.
> Mid-fi guy prefers them to the KT88.
> ...


Hi, nope referring to EL37 when switched to EL34 mode. Cheers


----------



## ThanatosVI

rulerofrecords said:


> Hi, nope referring to EL37 when switched to EL34 mode. Cheers


Then I unfortunately can't give any impressions,  but good to have it clarified


----------



## rulerofrecords

ThanatosVI said:


> Then I unfortunately can't give any impressions,  but good to have it clarified


Btw I'v got some interesting quotes from German dealers regarding HA-300 and Ha-6a. With the HA-300 it's 20% of list price - the HA-6a can be had for approx. 15% less than list price. So for the HA-6a France is remains the place with the best price. Unless somebody else knows something else ...


----------



## Fatdoi

monitoring the new McIntosh MHA200 amp...... see if there'll comparison between the two


----------



## DaYooper

Got my amp today, yipee. What it does for the HD800 is instantly apparent but... it needs a little burn time. That said I'm thinking I'm in for some really really exquisite listening in my future!


----------



## ThanatosVI

DaYooper said:


> Got my amp today, yipee. What it does for the HD800 is instantly apparent but... it needs a little burn time. That said I'm thinking I'm in for some really really exquisite listening in my future!


Enjoy, it's really a great sounding amp.


----------



## skylinekursk

ThanatosVI said:


> Enjoy, it's really a great sounding amp.


You are right...but this feeling that it can't be good as it is...so I'm waiting for some disappointment one day...I hope I'm wrong


----------



## DaYooper

I'm really enjoying this amp. Just sounds sweet with whatever I play through it and so many possible ways to use it given my library and inventory of equipment.

About a hundred hours of burn in.


----------



## Fatdoi (Feb 17, 2021)

DaYooper said:


> I'm really enjoying this amp. Just sounds sweet with whatever I play through it and so many possible ways to use it given my library and inventory of equipment.
> 
> About a hundred hours of burn in.


do you use EL34 or KT88?

Anyone knows how to do a poll on this thread with 34/88 preference?


----------



## DaYooper

It has the KT88 still. I haven't got around to trying the other ones yet.


----------



## ThanatosVI

DaYooper said:


> It has the KT88 still. I haven't got around to trying the other ones yet.


Those Gold lion KT88 are actually really good, especially considering the low price


----------



## skylinekursk

kt88 is really really good. I rolling tubes 1-2 times per month when I change HP and both types sounds good! Next one to try kt66


----------



## ThanatosVI

skylinekursk said:


> kt88 is really really good. I rolling tubes 1-2 times per month when I change HP and both types sounds good! Next one to try kt66


Never tried those,  please share your impressions afterwards


----------



## DaYooper (Feb 17, 2021)

What could be better, eh? Steely Dan, Cayin, HD800


----------



## rulerofrecords

DaYooper said:


> What could be better, eh? Steely Dan, Cayin, HD800


I'm thinking but can't actually come up with something significantly better ...


----------



## Jandu

DaYooper said:


> What could be better, eh? Steely Dan, Cayin, HD800



Maybe a glass of wine or an expresso, a good chair overlooking some perfect scenery. LOL


----------



## PortableAudioLover

Hello folks,
Just checking here, does this amplifier have two versions for two different voltages of 110V and 240V ?


----------



## DaYooper (Feb 20, 2021)

Pretty sure.
https://en.cayin.cn/products_info?itemid=127
Go there and look at the picture of the back.


----------



## AnimalOnDrums

I just saw one of these available in the UK from a guy on the Roon forums I frequent https://www.ukaudiomart.com/details/649708790-cayin-ha6a-headphone-amp/ . I am not getting rid of mine anytime soon, I really like this amp.


----------



## PortableAudioLover

AnimalOnDrums said:


> I just saw one of these available in the UK from a guy on the Roon forums I frequent https://www.ukaudiomart.com/details/649708790-cayin-ha6a-headphone-amp/ . I am not getting rid of mine anytime soon, I really like this amp.


what headphones do you use this with ? does it have a huge noise floor ?


----------



## DaYooper

PortableAudioLover said:


> what headphones do you use this with ?


HD800


----------



## ThanatosVI

PortableAudioLover said:


> Hello folks,
> Just checking here, does this amplifier have two versions for two different voltages of 110V and 240V ?


Yes their are different versions, no switch or anything. 
So you need to pay attention to get the right version


----------



## Magol79

Is the noise floor affected by the input signal level? I.e. is it higher when using the XLR input compared to RCA?


----------



## ThanatosVI

Magol79 said:


> Is the noise floor affected by the input signal level? I.e. is it higher when using the XLR input compared to RCA?


No it's not.


----------



## AnimalOnDrums

I use it with my Audeze LCD-3.  I love it.  The input choice does not affect noise floor, which I don't hear anyways.


----------



## Fatdoi

Will love to hear more reviews on low impedance and efficient headphones


----------



## skylinekursk

Andykong said:


> I assume you are referring to the RCA and XLR input impedance?  Never run into customer who needed this information.  I need to come back to you after Chinese New Year break.


Any news on this one??


----------



## skylinekursk

have been comparing with best Russian DIY amps past weekend . Dacs are sonic frontiers sfd2mk2 and krell studio


----------



## Andykong

skylinekursk said:


> Any news on this one??



47 KOhm


----------



## Gr3g277

Hello guys,

I wanted to share a little tube experiment I am doing at the moment with my ha-6a.

*disclaimer:*
First please, this my personal experience with my amp, please do not try to reproduce what I am doing here unless you know what you are doing, and then you are doing it at your own risk
What I verified in my amp, may not hold true for yours.

*SOME MORE TUBE ROLLING MADNESS :*

I have some 6sn7 lying around from my Freya preamp, and knowing that the 6sn7 is one , if not the best preamp tube available, I wanted to experiment a bit....

The 6sn7 have the same electrical parameters as a 12au7. BUT, it is octal based, and draws twice the heater current, and the heaters runs only in parallel.
So... not quite the drop in replacement right ?

Right, but not too complicated either !

To use a 6sn7 in place of a 12au7, one must first know if the 12au7 are used with heater in series (12.6V) or in parallel (6.3V).
the 12au 7 is a double triode, that means, two triodes in the same tube. The 12a7 family has the heater center tap on pin 9, and heaters on pins 4&5.





To Know if the tube is used with triodes in parallel or in series, you have to look inside the amp: if pins 4 and 5 are connected and pin 9 left unconnected, that means it is wired in series so 12.6v is applied.
If pin 4&5 are wired together, and pin 9 connected as well ( center tap ) that means a parallel connection is made and the heater voltage is therefore 6.3 V.

On inspection , I have noted that *MY *HA-6A is wired in 6.3V !!! so that means even more tube rolling possibilities are opening !!

*second disclaimer : the correct adapter (6.3V) must be used, never ever do this with a 12.6V adapter or fire will happen !
be absolutely sure you are using the correct adapter on the correct socket !*

with this out of my chest :

12bh7,6sn7,6cg7,6fq7..... are possible candidates !

so just put in an adapter and all is good right ?

wait my friend not so fast ! 

second we have to know if the power transformer can give us enough power without burning itself trying...
the 6SN7,12bh7,6cg7,6fq7... wants 0.6A of current for it's heater.
the 12au7 wants 0.3A.

that is twice the current ! and the power and rectifier tubes still needs to be powered as well...

So how one can do this safely ?

ask the manufacturer of the amp if the power transformer is overbuilt enough to withstand the load ?

I am therefore asking Mr @Andykong : Does the power transformer of the ha6a has enough current capacity to withstand the added total load of 0.6A when used with compatible tubes ? Even better would be to know exactly what is the rated amperage on the power transformer used in the ha 6a ?


lets do some calculation here on what is the amperage consumed from the stock tubes : based on the tubes datasheets. 

12au7*2 : 0.6A
kt88*2 : 3.2A
22de4*2 : 0.9A

total is 4.7 A.

putting 6sn7 in place of the 12au7 would take us to 5.3 A.
Problem is, we don't know if that is safe , as we don't know the rating from the power tranny.

But, what if we use a less current hungry power tube ? the el34 draw 1.5A per tube, so the problem is the same...
Here comes the 6l6 tube, with it's current draw of 0.9A only !

Those of you who read that thread since last year, knows that it is one of my favorite tubes in this amp 
so with the 6l6 installed we have :
12au7*2 : 0.6A
6l6*2 : 1.8A
22de4*2 : 0.9A
Total : 3.3A

so know adding 0.6 A to the total for the 6sn7 tubes will get us to 3.9A only... even less than stock with the kt88 !

so here you go : ( I know It looks kinda silly.... )





I had to put an extra socket saver between the adapter and the socket, as the adapter would not fit in the small recessed cutout in the amp chassis.


So this looks like crap right... but let me tell you, Holy mama ! the sound is know nothing short than amazing !!!
The noise floor is lower, less microphonic, hiss is almost completely gone and the music is just superb.
With my utopia, which is very sensitive , the hiss can only be heard a tiny bit with the highest impedance setting.
The bass is tighter, more full bodied, soundstage is wider, highs are super smooth, music flows freely with an added sense of fluidity.

The tubes here are nothing really special, new production Tung sols 6sn7 GTB pulled from my main system Freya preamp.

I am now eager to try it with kt88 also, And waiting eagerly for @Andykong to respond

The tube preamp hierarchy is respected the 6sn7 are far better than any 12au7 Nos or new production.

Now this opens even more possibilities with that .6A heater : 

*the 6cg7* : a 9pin 6.3V tube ( adapter still needed ) that is basically a 6sn7 in smaller envelope. with an internal shield that reduce noise and increase separation.
*the 6fq7* : Same as 6Cg7, only without the shield. A lot of great NOS options available for cheap
*the 12bh7* : direct drop in replacement ! no adapter needed, only the heater at .6A as the on above.


I have some of those coming on the way.... will be reporting here

Yes I know I am crazy, In France we call it not an audiophile, but an audiopath....

see you next time fellas !


----------



## Relaxasaurus

Gr3g277 said:


> Hello guys,
> 
> I wanted to share a little tube experiment I am doing at the moment with my ha-6a.
> 
> ...


Uhh are you selling adapters? This is amazing!

I have some 6sn7 -> KT88 adapters for my Euforia and I love the results. I can only imagine how a quality 6ns7 sounds on the HA-6A. Great work!!


----------



## kimdeug

Gr3g277 said:


> Hello guys,
> 
> I wanted to share a little tube experiment I am doing at the moment with my ha-6a.
> 
> ...





Gr3g277 said:


> Thanks a lot.


Thanks a lot from New Zealand.

Absolutely amazing job has been done with a lot of research and thoughts.
Highly appreciated your time and efforts.
I new you will do it, when I saw the question about  6.3V or 12.6V for 12AU7.
I also prefer 6SN7 tube sound more than 12AU7.
Currently I try to make aluminium ring/socket saver for 12AU7 tubes, just for aesthetic view and elevate 12AU7 little bit up.
Similar aluminium ring like around the KT88/EL34 socket.
With this Covid situation it is a big delay of worldwide delivery for my tubes orders.
Half already arrived, but another half still on the way (3 months).

Keep Rolling!
Regards,
Kim


----------



## Gr3g277

Relaxasaurus said:


> Uhh are you selling adapters? This is amazing!
> 
> I have some 6sn7 -> KT88 adapters for my Euforia and I love the results. I can only imagine how a quality 6ns7 sounds on the HA-6A. Great work!!



Guys please if you want to try this do it only wirh 6l6 tubes on the power.
Unfortunately i couldnt check the rating of the power transformer on inspection. 

So unless cayin says that the power tranny has enough headroom, i would advise against doing it...

6sn7 to kt88  adapter ????  Never heard of that ! Is it any good ?





kimdeug said:


> Thanks a lot from New Zealand.
> 
> Absolutely amazing job has been done with a lot of research and thoughts.
> Highly appreciated your time and efforts.
> ...


Thank you my friend !

I love the 6sn7, it is an amazing tube !
Looking forward to your experiment !


----------



## Gr3g277

For those you want to know here is the adapters I used

https://a.aliexpress.com/_mrUwWRV

Socket savers are pretty easy to find !


----------



## Andykong (Mar 11, 2021)

Gr3g277 said:


> Hello guys,
> 
> I wanted to share a little tube experiment I am doing at the moment with my ha-6a.
> 
> ...



I sincerely appreciate your effort to expand the tube rolling possibilities with HA-6A, I am sure all audiophile will understand the effort and dedication behind this sharing.

However, what you did is a very high risk option, it goes against the tube replacement advice we stated in the user manual, and is therefore considered abuse application from warranty point of view.  Under this circumstances, there is no way I can endorse or contribute to your work directly.  The worst case scenario, someone run into trouble and toasted his amplifier, and then he ask his dealer for warranty because "Andy Kong provided the information for this".  The tough part is, my dealer in Thailand or Japan (for example) cannot turn down customer request by quoting your disclaimer, they probably unaware of your disclaimer to start with.


----------



## Gr3g277

hello andykong,

I appreciate your answer, and totally understand your point of view.
My Ha-6a is past it's warranty date of 1year, so yes I personally took the risk to try it for myself.

I also made big disclaimers and was particularly clear that doing so has it's own risks and that any person attempting to do it accepts the risk of voiding the warranty, and that the manufacturer, you, myself, or the head-fi forum can't be hold responsible for any damage that may occur.

In life I am an It systems engineer working as consultant for big companies,  I have education in electronics, and used to repair electronic cards, so I have some background... my post above is only for recreational/educational purpose 

In the future I will post other disclaimers of the sort If I happen to do some more experiments with my amp 

I will understand if you are therefore not willing to answer my question about the Amperage rating of the power transformer....

Tube rolling in this amp is just too much fun, and I think that as educated adults, we can share our fun experiments together. I firmly believe that this what this forum is all about


----------



## skylinekursk

Hello Gentlemen! Thanks for sharing tube rolling experience! 
what is most fatty sounding tube for ha6a?


----------



## kimdeug

Andykong said:


> I sincerely appreciate your effort to expand the tube rolling possibilities with HA-6A, I am sure all audiophile will understand the effort and dedication behind this sharing.
> 
> However, what you did is a very high risk option, it goes against the tube replacement advice we stated in the user manual, and is therefore considered abuse application from warranty point of view.  Under this circumstances, there is no way I can endorse or contribute to your work directly.  The worst case scenario, someone run into trouble and toasted his amplifier, and then he ask his dealer for warranty because "Andy Kong provided the information for this".  The tough part is, my dealer in Thailand (for example) cannot turn him down by quoting your disclaimer.





skylinekursk said:


> Hello Gentlemen! Thanks for sharing tube rolling experience!
> what is most fatty sounding tube for ha6a?


I have found that included Genalex Gold Lion (Russian) are very good. Genalex Gold Lion (made in England) and KT88 GEC may be 10% fatty/Juicer in sound, but with price 20 times more. NOS 6550 Coke bottle shape (Tungsol, RCA, Sylvania) will be smooth and creamy too. But again. I prefer KT88 sound. Have ordered KT88-T Psvan MK II and JJ KT88. As I said before, the power tube range is quite limited, So I am more concentrated on 12AU7 rolling as the range is huge. 

Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> I have found that included Genalex Gold Lion (Russian) are very good. Genalex Gold Lion (made in England) and KT88 GEC may be 10% fatty/Juicer in sound, but with price 20 times more. NOS 6550 Coke bottle shape (Tungsol, RCA, Sylvania) will be smooth and creamy too. But again. I prefer KT88 sound. Have ordered KT88-T Psvan MK II and JJ KT88. As I said before, the power tube range is quite limited, So I am more concentrated on 12AU7 rolling as the range is huge.
> 
> Regards,
> Kim


Well there are also the 
TaD KT88-STR blackplates 
KR KT88 
EAT KT88

Those 3 received plenty of praise, however at a higher price than Gold lions. 

12au7 rolling is considerably cheaper


----------



## Gr3g277

ThanatosVI said:


> Well there are also the
> TaD KT88-STR blackplates
> KR KT88
> EAT KT88
> ...


Yes I have received this morning Tad KT88-STR Blackplates, they are on the burn in phase now but they sound already very nice right out of the box, more on those later !

usually if you want to fatten the sound, go For JJ power tubes, like JJE34L or JJ6550.
Maybe even the JJ KT88.

I have a set of JJ El34, and they are indeed very creamy, but highs are too much recessed for my liking.
If you are more fan of kt88, usually the 6550 is fatter sounding while keeping about the same power

as for input tubes, amperex bugle boys, or Nos mullards usually do the trick as well.


----------



## Zachik

Gr3g277 said:


> Yes I have received this morning Tad KT88-STR Blackplates, they are on the burn in phase now but they sound already very nice right out of the box, more on those later !


How do these compare to the Gold Lions? 
Have you tried RAM KT-88 tubes?


----------



## Gr3g277

Zachik said:


> How do these compare to the Gold Lions?
> Have you tried RAM KT-88 tubes?


I have to put the gold lions back in the amp, and the blackplates need a bot more burn in.
from memory I will say that soundstage seems wider, and tone a bit richer, bass seems is great, but cannot confirm for the moment.
I will report back when I have swapped between them


----------



## kimdeug (Mar 12, 2021)

ThanatosVI said:


> Well there are also the
> TaD KT88-STR blackplates
> KR KT88
> EAT KT88
> ...


Yes, sure.
I did not mentioned these three names, because for me they looks like rebranded Shuguang KT88 tubes.
Also, have found that Chinese manufactures start to mimic JJ KT88 tubes, then original JJ tubes are manufactured on old Tesla equipment.


----------



## ThanatosVI

kimdeug said:


> Yes, sure.
> I did not mentioned these three names, because for me they looks like rebranded Shungan KT88 tubes.
> Also, have found that Chinese manufactures start to mimic JJ KT88 tubes, then original JJ tubes are manufactured on old Tesla equipment.


All 3 are current production tubes.
The TAD is based on a british Design while the other tubes are Tesla reissues


----------



## Zachik

Gr3g277 said:


> I have to put the gold lions back in the amp, and the blackplates need a bot more burn in.
> from memory I will say that soundstage seems wider, and tone a bit richer, bass seems is great, but cannot confirm for the moment.
> I will report back when I have swapped between them


Which do you think has wider sound stage and sounds richer with more bass? The TAD or Gold Lions? (I have read your post couple times, and it could be interpreted both ways, I think)

Also, is that the right tube:




Does NOT saying Blackplate on it...

The photo from the manufacturer website does:



(but I prefer to buy locally and avoid international shipping, plus cheaper in the US for me...)
So, is it the same tube or 2 different grade levels (which could explain the cheaper price of the one that does not say "Blackplate" on it)?


----------



## Zachik

OK... apparently they DO have 2 grade levels:





The US places seems to be selling the cheaper (non-Blackplate) version.


----------



## Gr3g277

Zachik said:


> OK... apparently they DO have 2 grade levels:
> 
> The US places seems to be selling the cheaper (non-Blackplate) version.


Yes there are 2 grade levels, the str version, which is cheaper, and the blackplates series.
The second picture is the tube I have, and I was talking about this tube in my previous post. Sorry if it was unclear, I am not a native english speaker 

The tubes branded TAD, means tube amp doctor, a german company specialized in guitar amp parts.
TAD tubes are made in the shuguang factory in china. They are made using a special equipment and tooling, with a schematic specific to them.They are then pre-burned in and selected and matched in germany, hence the "premium selected" branding.
The blackplate series, are basically the same, but the anodes have a black special coating, which is supposed to help with linearity and heat dissipation.


I think they are great tubes, very reliable, and have a sound of their own, I mean those are not just plain rebranded shuguang tubes. ( could be the case for some small tubes , but i don t know for sure )
Further listening confirms my early impressions, a bit richer sounding than the gold lions, but I am not sure yet if that is because the highs are recessed or if they are neutral with more body.
I have only 2hours of listening on them so too early to make a statement.

Moreover I use my desktop computer as a source, and I have a usb pci filter card coming with a linear power supply, as I figured playing with the bifrost 2 usb and coax input from the reclocker produced vastly different results.

 by the way @ThanatosVI was the psaudio powerplant an improvement in noise floor for the ha-6a ?


----------



## ThanatosVI

Gr3g277 said:


> by the way @ThanatosVI was the psaudio powerplant an improvement in noise floor for the ha-6a ?


No, it didn't alter the noise. It did improve the sound tho.

All noise I had was from one of the stock 12au7 with different tubes it was completely silent


----------



## Zachik

Gr3g277 said:


> Sorry if it was unclear, I am not a native english speaker


Your English is great. I am not a native English speaker, too 



Gr3g277 said:


> Yes there are 2 grade levels, the str version, which is cheaper, and the blackplates series.
> The second picture is the tube I have, and I was talking about this tube in my previous post.


Where did you buy them from? I am in the US, and rather not order from Germany (will probably take well over a month to arrive...).



Gr3g277 said:


> I have only 2hours of listening on them so too early to make a statement.


I truly appreciate your impressions, and totally understand your caveats


----------



## Gr3g277

Zachik said:


> Your English is great. I am not a native English speaker, too
> 
> 
> Where did you buy them from? I am in the US, and rather not order from Germany (will probably take well over a month to arrive...).
> ...


I bought them direct from tad in germany, took a few days to arrive with ups 
But I live in france not far from the german border... so that helps with shipping, no idea how long it will take to arrive in the us, I will say TAD are very nice to deal with.

I also got nos sylvania 12bh7 from them
That I need to try


----------



## skylinekursk

Hi gentlemen,
Does any one saw what inside of the amp? Can't google photos...


----------



## SolidSlug

Where did you all buy your HA-6A?


----------



## DaYooper

SolidSlug said:


> Where did you all buy your HA-6A?


Musicteck, shipped from China.


----------



## SolidSlug

Are the hiss/hum/noise issues fixed at this point?


----------



## DaYooper

I have zero noise issues.


----------



## skylinekursk

SolidSlug said:


> Where did you all buy your HA-6A?


Moscow... 
I use planar phones, so no hiss/hum/noise


----------



## kimdeug (Mar 19, 2021)

SolidSlug said:


> Where did you all buy your HA-6A?


Hi from New Zealand

Rapallo shop, Auckland, New Zealand.
The first unit was with very loud hiss/humm noise around 20dB. It has been replaced with another new unit by Cayin and it took around 6 months.
The second unit is much better, but still has hiss nose (but now it is not too noticeable. I can accept it as normal valve noise during the tube operation).
Low sensitivity headphones and planars are not revealing any hiss/humm noise. Mostly it affects high sensitivity (more than)>100dB  dynamic headphones.

Regards,
Kim


----------



## SolidSlug

Thanks, all!


----------



## atya35mm

Hi all, 

First post here as I bit the bullet and ordered the HA-6A after following this thread for a bit. To all the seasoned users here, would be keen to hear your favorite tubes combination for the type of songs you listen to? 

Hopefully the question isn't too general, but I've got some orders of KT88 / El34 as well as 12au7s lined up, and keen to hear others experience with their tube rolling journey.  

Cheers

Adrian


----------



## Fatdoi

atya35mm said:


> Hi all,
> 
> First post here as I bit the bullet and ordered the HA-6A after following this thread for a bit. To all the seasoned users here, would be keen to hear your favorite tubes combination for the type of songs you listen to?
> 
> ...


Congrats on your purchase.... which headphones you will run it on?


----------



## atya35mm

Fatdoi said:


> Congrats on your purchase.... which headphones you will run it on?


Hi Fatdoi, thanks! Will be on the Susvara, looking forward to it, and hopefully power isn't an issue.


----------



## Fatdoi

atya35mm said:


> Hi Fatdoi, thanks! Will be on the Susvara, looking forward to it, and hopefully power isn't an issue.


Great...... what amp you using now?


----------



## atya35mm

Fatdoi said:


> Great...... what amp you using now?


Currently using the A90/D90 stack for SS, which sounds good and very clean on my ear, but still quite new to headphones so looking forward to trying tube amps.


----------



## Fatdoi

atya35mm said:


> Currently using the A90/D90 stack for SS, which sounds good and very clean on my ear, but still quite new to headphones so looking forward to trying tube amps.


I'm also using A90 but only powers ZMFs and Utopia.... Nothing as taxing as your Susvara


----------



## atya35mm

Fatdoi said:


> I'm also using A90 but only powers ZMFs and Utopia.... Nothing as taxing as your Susvara


yes can't wait to get the HA-6A to see how it handles this beast. Might have to trade the headphone for something else if there's issues. eek.


----------



## wgkwgk

Any comparisons to Decware Taboo mk4?  I'm on the fence.


----------



## skylinekursk

hello gentlemen! 
I'm wonder how input tubes can change signature? I put NOS Sylvania few month ago but I can't say there any huge difference...may be I should look at RCA 6189 for more heavy-genre tube? I came from 6SN7 family from previous amp and it was quite clear - RCA and Sylvania early tubes are for metal/rock.... 

p.s. just found out TAD released new 6l6 redbased tube..


----------



## wgkwgk

Andykong said:


> We don't know the figure, and we don't intend to publish the detail output impedance.


Why not?  I'm contemplating buying one but this surprises me.  Especially for Cayin.


----------



## wgkwgk

Anyone???


----------



## skylinekursk (Mar 30, 2021)

Hi to all!
Just found strange issue yesterday.... I use RCA for interconnect but HP in XLR connector... I tried use SE 6.3 for same HP and it was much better sounding phones.... much more clear left/right channels, more tight and wider sound.... is it because RCA for XLR scheme of connection or just XLR output is worst sounding? Sound like wrong phase...

Thanks!

UPDATE: bad cables...


----------



## ThanatosVI

skylinekursk said:


> Hi to all!
> Just found strange issue yesterday.... I use RCA for interconnect but HP in XLR connector... I tried use SE 6.3 for same HP and it was much better sounding phones.... much more clear left/right channels, more tight and wider sound.... is it because RCA for XLR scheme of connection or just XLR output is worst sounding? Sound like wrong phase...
> Thanks!


I can't report something like thst from my experience. 

I also used RCA in and both outs 1/4" and XLR. XLR did sound better for me. 

Therefore I think it mighr have to do with you headphone cable quality, and your SE cable is superior maybe


----------



## skylinekursk (Mar 30, 2021)

ThanatosVI said:


> I can't report something like thst from my experience.
> 
> I also used RCA in and both outs 1/4" and XLR. XLR did sound better for me.
> 
> Therefore I think it mighr have to do with you headphone cable quality, and your SE cable is superior maybe


you are right


----------



## skylinekursk

does anyone has issue with memory of last used mode after restart? UL/triode 
my amp always turn on Triode after start


----------



## ThanatosVI

skylinekursk said:


> does anyone has issue with memory of last used mode after restart? UL/triode
> my amp always turn on Triode after start


Mine had the same from the very beginning, even though the manual states that it remembers the setting.


----------



## Magol79 (Apr 3, 2021)

Hello!

I am looking for a high end tube amp for my ZMF headphones.

Is anyone using this amp with high Ohm dynamic headphones? I have the VO and Auteur and I am trying to find out if they would work well with this amp. From earlier posts in the thread people seem to prefer this amp with planars.

Also, my current headphone cables are XLR terminated Forza cables, so I would like to use those with this amp.


----------



## Fatdoi (Apr 3, 2021)

Magol79 said:


> Hello!
> 
> I am looking at into a high end tube amp for my ZMF headphones.
> 
> ...


I've been looking at this one since the beginning also to pair with ZMFs like you.... seems high impedance HP are ok with this amp.... but I spent the amp budget on Ironwood VO... now need to start saving again


----------



## atya35mm

Hi all got my amp this morning, and happy to report back Cayin HA6A is driving the Susvara with no issues and much better than my solid state amp at first impression (topping a90). On the stock tubes so far, I can hear more details than the a90 and everything sounded, more in front where a90 I feel is more recessed somehow. I do typically listen at lower level. Currently on low impedance setting and volume knob is only at 9.30. Tried UL and TR and prefer TR at the moment, with less in your face bass. Overall, very happy and relieved I have made the right choice for the headphone.


----------



## MasonSafari

Hi All
I have been always in solid-states amps, currently have chord Dave and Focal Eutopia , HD800s ans Sony MDR-Z1R ...also I have hifi speaker system with Luxman amp...recently I get into Vynil more as now i guess I prefer the warmth to pure accuracy...so now I'm thinking if I add Tube headphone amp to my DAVE and I should get a nice warmth results...I was considering WOO WA22 but then after reading this thread I'm also considering HA6A...so my questions are :
- can both WA22 and HA6A drive my 3 headphones?
- im interested to put the tube amp in my hifi as pre amp to give some warmth...I know WA22 has the pre amp balanced outlet but anyone has used the HA6A as pre amp ?
- i need to put the tube amp in my hifi cabinet which is open from every dide but the clearance on the above amp will be 20cm, will this work for me ?

Thanks in advance
Mason


----------



## Fatdoi

atya35mm said:


> Hi all got my amp this morning, and happy to report back Cayin HA6A is driving the Susvara with no issues and much better than my solid state amp at first impression (topping a90). On the stock tubes so far, I can hear more details than the a90 and everything sounded, more in front where a90 I feel is more recessed somehow. I do typically listen at lower level. Currently on low impedance setting and volume knob is only at 9.30. Tried UL and TR and prefer TR at the moment, with less in your face bass. Overall, very happy and relieved I have made the right choice for the headphone.


Congrats on your purchase, are you using the KT88 or EL34 tubes?


----------



## Fatdoi

MasonSafari said:


> Hi All
> I have been always in solid-states amps, currently have chord Dave and Focal Eutopia , HD800s ans Sony MDR-Z1R ...also I have hifi speaker system with Luxman amp...recently I get into Vynil more as now i guess I prefer the warmth to pure accuracy...so now I'm thinking if I add Tube headphone amp to my DAVE and I should get a nice warmth results...I was considering WOO WA22 but then after reading this thread I'm also considering HA6A...so my questions are :
> - can both WA22 and HA6A drive my 3 headphones?
> - im interested to put the tube amp in my hifi as pre amp to give some warmth...I know WA22 has the pre amp balanced outlet but anyone has used the HA6A as pre amp ?
> ...


your headphones aren't too hard to drive so I think this amp can handle them with ease but I don't think HA6A or HA300 have pre amp out...


----------



## DaYooper

HA-6A does not do pre-amp.


----------



## ThanatosVI (Apr 7, 2021)

Fatdoi said:


> your headphones aren't too hard to drive so I think this amp can handle them with ease but I don't think HA6A or HA300 have pre amp out...


Ha 300 has pre outs

Edit: Turns out I was wrong, no pre outs


----------



## DaYooper

Are speaker outs the same as pre amp outs? Because the HA-300 has speaker out at 8W each.


----------



## ThanatosVI

DaYooper said:


> Are speaker outs the same as pre amp outs? Because the HA-300 has speaker out at 8W each.


No they are not, seems I was mistaken.
Ha300 has only speaker Outs and no pre outs


----------



## atya35mm

Hi all, quick query hoping someone can assist.

Does switching the input to Cayin HA6A from using balanced input (4v) to RCA input (2v) ended up lowering the balanced output power to the headphone?


----------



## atya35mm

*double post by mistake*


----------



## Fatdoi

atya35mm said:


> Hi all, quick query hoping someone can assist.
> 
> Does switching the input to Cayin HA6A from using balanced input (4v) to RCA input (2v) ended up lowering the balanced output power to the headphone?


the amp is not a true balanced design so it converts XLR signal to SE then converts SE back to XLR out so i don't think your change of input will affect the output


----------



## atya35mm

phew thanks, i need all the power i can get so good to know Qutest with RCA is alright. Thanks Fatdoi!!


----------



## skylinekursk (Apr 9, 2021)

Fatdoi said:


> the amp is not a true balanced design so it converts XLR signal to SE then converts SE back to XLR out so i don't think your change of input will affect the output


Hello!
So that means RCA and SE is true for the amp? Very interesting how that conversion effects on quality... I was thinking amp is true balance and changed all cables to XLR output and now it's better to go back to SE....what a mess)

One thing is not clear for me. It says balance has more output power in every mode and any tube but what that means? Depends on DAC voltage on RCA or XLR? If I'm correct - when use RCA input power on every output is the same... correct? 

Thanks


----------



## Fatdoi (Apr 9, 2021)

skylinekursk said:


> Hello!
> So that means RCA and SE is true for the amp? Very interesting how that conversion effects on quality... I was thinking amp is true balance and changed all cables to XLR output and now it's better to go back to SE....what a mess)
> 
> One thing is not clear for me. It says balance has more output power in every mode and any tube but what that means? Depends on DAC voltage on RCA or XLR? If I'm correct - when use RCA input power on every output is the same... correct?
> ...


Cayin official diagrams both HA6A and HA300 definitely have XLR input transformer.... imo RCA input will have less signal loss than XLR input...


----------



## atya35mm (Apr 9, 2021)

I'm no expert in this, but i'm "hoping" when it says balance has more output power, it's referring to the output side of things i.e. balanced output has more power vs. single ended (XLR out vs std headphone jack out)


----------



## DaYooper

atya35mm said:


> I'm no expert in this, but i'm "hoping" when it says balance has more output power, it's referring to the output side of things i.e. balanced output has more power vs. single ended (XLR out vs std headphone jack out)


What on earth are you trying to drive that would require more power than HA-6A can deliver?


----------



## skylinekursk

DaYooper said:


> What on earth are you trying to drive that would require more power than HA-6A can deliver?


Oh it's easy to answer....1266, lcd-4, Myst Ortophones (18 Ohm, 80 dB - ha6a is definitely not enough), he6, Snorry NM1...the funny thing is these are TOP end HP....


----------



## atya35mm

DaYooper said:


> What on earth are you trying to drive that would require more power than HA-6A can deliver?


well Susvara....


----------



## DaYooper (Apr 9, 2021)

And are they driven adequately?

I see in your earlier post you said they were.


----------



## atya35mm

DaYooper said:


> And are they driven adequately?


I'm quite new to this hobby, but I think they are in KT88 mode, but bass seems loose in EL34 mode which I'm not sure if that's just EL34 signature or due to the lower power output of the EL34 mode.


----------



## DaYooper

I see, welcome to the sport. At this level of investment I just had to quit chasing that last 5% of sonic improvement so getting another multi-thousand dollar headphone is off the table. I use my HA-6A with some pretty good phones and have had no problem driving them to ear damaging levels if so desired.  The phones used so far: Utopia, HD800/HD800S, Klipsch HP-3. I have several others I just haven't got around to plugging in yet but nothing like Susvara.


----------



## ThanatosVI

skylinekursk said:


> Oh it's easy to answer....1266, lcd-4, Myst Ortophones (18 Ohm, 80 dB - ha6a is definitely not enough), he6, Snorry NM1...the funny thing is these are TOP end HP....


Well 1266, lcd4 and he6 can all be driven to ear bleeding levels with the Ha-6a if you feed it thr industry Standard of 2V via RCA or 4V via XLR.
Don't know about the rest


----------



## skylinekursk

ThanatosVI said:


> Well 1266, lcd4 and he6 can all be driven to ear bleeding levels with the Ha-6a if you feed it thr industry Standard of 2V via RCA or 4V via XLR.
> Don't know about the rest


yes, of course...but....bleeding level of volume is not criteria of enough power to HP. Bass control, clear highs this is sign of good drive.. listen ha6a with any of these HP and they could sound like they are good powered then switch to another amp with more power and you will hear the difference. 
I trying to say HA6A can drive any HP on the market, but it can't show full potential of "power hungry" phones....


----------



## ThanatosVI

skylinekursk said:


> yes, of course...but....bleeding level of volume is not criteria of enough power to HP. Bass control, clear highs this is sign of good drive.. listen ha6a with any of these HP and they could sound like they are good powered then switch to another amp with more power and you will hear the difference.
> I trying to say HA6A can drive any HP on the market, but it can't show full potential of "power hungry" phones....


Well the problem here is,  how the amp delivers the power not how much it can deliver in total (e.g. a formula S has very low total power output but can drive an abyss 1266 to its potential)

This is a very complex topic and not easily answered with "more power is better", although there often is a correlation.

Sure the Ha-6a is not the be all end all here, but power output is not the issue


----------



## skylinekursk

ThanatosVI said:


> Well the problem here is,  how the amp delivers the power not how much it can deliver in total (e.g. a formula S has very low total power output but can drive an abyss 1266 to its potential)
> 
> This is a very complex topic and not easily answered with "more power is better", although there often is a correlation.
> 
> Sure the Ha-6a is not the be all end all here, but power output is not the issue


I appreciate so much if you can tell more about power delivering... this is what most of audiophiles don't know but it's really important information! may be you know some articles with details? 
Thanks!!!


----------



## Fatdoi

atya35mm said:


> I'm quite new to this hobby, but I think they are in KT88 mode, but bass seems loose in EL34 mode which I'm not sure if that's just EL34 signature or due to the lower power output of the EL34 mode.


EL34 signature is killer mid range..... KT88 is a great all round tube


----------



## Fatdoi

ThanatosVI said:


> Well 1266, lcd4 and he6 can all be driven to ear bleeding levels with the Ha-6a if you feed it thr industry Standard of 2V via RCA or 4V via XLR.
> Don't know about the rest


my audio friend always like to use this comparison..... both driving at the same speed, a 6000cc V8 leisurely burring @ 2000rpm or a 2000cc turbo 4 screaming @ 7000rpm


----------



## atya35mm

Fatdoi said:


> EL34 signature is killer mid range..... KT88 is a great all round tube


Thanks yes def sticking with KT88 for now.


----------



## skylinekursk

It's time to order 6L6GC...
just found new tube from TAD.... tube has higher DC plate voltage - 800... is it suitable for HA6-A instead of older version listed below?

https://www.tubeampdoctor.com/en/6l6wgc-str-blackplate-ge-style-tad-premium-matched
or
https://www.tubeampdoctor.com/en/6l6gcm-str-redbase-tad-premium-selected


----------



## Gr3g277

skylinekursk said:


> It's time to order 6L6GC...
> just found new tube from TAD.... tube has higher DC plate voltage - 800... is it suitable for HA6-A instead of older version listed below?
> 
> https://www.tubeampdoctor.com/en/6l6wgc-str-blackplate-ge-style-tad-premium-matched
> ...


You will be fine with either, the dc plate voltage is only a max rating on the datasheet.
The 6l6wgc blackplate is one of my favorite tube for this amp.
I have not tried the new red base version yet. If you get those I wish to know how they sound like


----------



## Andykong (Apr 17, 2021)

skylinekursk said:


> Hello!
> So that means RCA and SE is true for the amp? Very interesting how that conversion effects on quality... I was thinking amp is true balance and changed all cables to XLR output and now it's better to go back to SE....what a mess)
> 
> One thing is not clear for me. It says balance has more output power in every mode and any tube but what that means? Depends on DAC voltage on RCA or XLR? If I'm correct - when use RCA input power on every output is the same... correct?
> ...





atya35mm said:


> I'm no expert in this, but i'm "hoping" when it says balance has more output power, it's referring to the output side of things i.e. balanced output has more power vs. single ended (XLR out vs std headphone jack out)



The concept is correct, but is based on non-transformer coupled Solid state amplifier.

To describe the HA-6A circuit correctly, it is balanced input, single-ended amplification and balanced output.  The HA-6A is a transformer coupled amplifier.  With output transformer in the final output stage, it is fairly straight forward to "generate" a negative phase in the output signal, so both single-ended and balanced output are "original" output from the transformer, we don't take the single-end output and then convert it into balanced output like other  non-transformer-coupled solid state amplifier.

On the other hand,  HA-6A "converts" balanced input into single-ended before feeding the signal to 12Au7.

We opt for single-ended amplification because that's the best sounding design for tube based amplification in our opinion.  For fully balanced tube amplification with the same choice of tube, we need to use set of four EL34/KT88 and set of four 12AU7,  that will limited your tube rolling practise because matched quad set of high quality vacuum tube is not only expansive but also difficult to come by.  On the other hand, the amplifier will be more powerful, sounds more accurate, but with less harmonic and intimacy.  The question is, when you select a tube amplifier, do you want it to be more accurate? or do you want it to have richer harmonic?


----------



## skylinekursk

Andykong said:


> The concept is correct, but is based on non-transformer coupled Solid state amplifier.
> 
> To describe the HA-6A circuit correctly, it is balanced input, single-ended amplification and balanced output.  The HA-6A is a transformer coupled amplifier.  With output transformer in the final output stage, it is fairly straight forward to "generate" a negative phase in the output signal, so both single-ended and balanced output are "original" output from the transformer, we don't take the single-end output and then convert it into balanced output like other  non-transformer-coupled solid state amplifier.
> 
> ...


My choice is definitely for richer harmonic =) 
Thanks for detailed answer


----------



## ThanatosVI

Andykong said:


> We opt for single-ended amplification because that's the best sounding design for tube based amplification in our opinion


Many other high end Tube amplifier manufacturers share that opinion


----------



## Andykong

atya35mm said:


> I'm quite new to this hobby, but I think they are in KT88 mode, but bass seems loose in EL34 mode which I'm not sure if that's just EL34 signature or due to the lower power output of the EL34 mode.





Fatdoi said:


> EL34 signature is killer mid range..... KT88 is a great all round tube


I assume when you refer to KT88 mode and EL34 modes, you have actually swapped the output tubes and then change the red button on the back panel.  It would be a totally different story if you only flip the red button but didn't change the tubes.

KT88 output is slightly higher then EL34, but only slightly, it is not significantly enough to cause the different you heard, so what  you heard are mainly different sound signature of sound signature of the KT88 and EL34.


----------



## Andykong (Apr 17, 2021)

skylinekursk said:


> Oh it's easy to answer....1266, lcd-4, Myst Ortophones (18 Ohm, 80 dB - ha6a is definitely not enough), he6, Snorry NM1...the funny thing is these are TOP end HP....





skylinekursk said:


> yes, of course...but....bleeding level of volume is not criteria of enough power to HP. Bass control, clear highs this is sign of good drive.. listen ha6a with any of these HP and they could sound like they are good powered then switch to another amp with more power and you will hear the difference.
> I trying to say HA6A can drive any HP on the market, but it can't show full potential of "power hungry" phones....



Maybe the answer is not simple as that.

Have you heard these power hungry phones in FULL POTENTIAL?  Can you share with us your reference of full potential of 1266, lcd-4, Myst Ortophones, he6, Snorry NM1? So that we can find out how far is HA6A from full potential of these headphones? Or will there be such a headphone amplifier that can drive all these headphones to full potential at $2500 budget? or at $5000 budget?  And will it drive relative sensitive headphones such as Focal Utopia and Stella, Audio Technica ATH-L5000, and Ultrasone Jubilee Edition 25 satisfactory?

By the way, I thought you said HA-6A can drive the Myst Ortophones to very impressive level?



skylinekursk said:


> Hi, guys!
> Just quick update... tried those "heavy" headphones Myst Ortophones on my HA-6A and it performed very impressive. I think abyss1266, he6, lcd4 is not problem for amp...
> 2 NOS 12au7 Sylvania's arrived and be tested on weekend...
> 
> Just wondering...is it possible to connect 2 pair of HP (xlr+se) and just switch between during amp work?



My friend, I am being sarcastic, because I think you have taken the wrong turn here.  In my humble opinion, you won't find a headphone amplifier that can drive all the TOTL headphones to full potential.  Maybe you can find an amplifier to deliver  enough power to drive these headphone to what you called full potential electrically, but what about sound signature?  Can one amplifier offer perfect synergy to all TOTL headphones? In my experience, a headphone amplifier with satisfactory handling power and perfect sound signature synergy will outperform another headphone amplifier with "full potential" handling power but lack of synergy.  Base on this observation, if your aim is to find one amplifier that can "do it all", then you should spend more attention to sound signature customisation.  In fact, HA-6A is one of the best amplifier in this department.  The only headphone amplifier that I have heard in person that outperform HA-6A in sound signature customisation is Cavalli's Liquid Glass.

I don't consider HA-6A as an end-game tube headphone amplifier.  At this price and design, the HA-6A is hardly an cost-no-objective implementation, and we have obviously compromised absolute performance for versatility.  It's a fun and high quality headphone amplifier instead of an end-game.


----------



## DaYooper (Apr 17, 2021)

Andykong said:


> It's a fun and high quality headphone amplifier


And there it is!

By the way, I just received the C9 as well. It is another fun and high quality amp from Cayin and IMO a fine compliment to the HA-6A.


----------



## ThanatosVI

Andykong said:


> I don't consider HA-6A as an end-game tube headphone amplifier. At this price and design, the HA-6A is hardly an cost-no-objective implementation, and we have obviously compromised absolute performance for versatility. It's a fun and high quality headphone amplifier instead of an end-game.


Totally agree here.
It's very versatile indeed. For the American and Chinese price it offers killer Performance!
Not so much in most european countries where it costs 50% more for no reason.

In the 2.5k range I can totally recommend it though.


----------



## Barnstormer13 (Apr 18, 2021)

Andykong said:


> I don't consider HA-6A as an end-game tube headphone amplifier.  At this price and design, the HA-6A is hardly an cost-no-objective implementation, and we have obviously compromised absolute performance for versatility.  It's a fun and high quality headphone amplifier instead of an end-game.



$2,500 is plenty end game enough for me. Don’t own an HA-6A, but thinking about it in a year or so.

In my experience good tube amps are magic with high impedance dynamic driver headphones. At least with the amps I’ve listened to.

My working theory is the magic starts falling off as the impedance and efficiency of the headphones drop, A high end tube amp can extend the range but it still does best with high impedance and high efficiency. 
That’s not even touching on the synergy that can happen with well matched gear.


----------



## ThanatosVI

Barnstormer13 said:


> $2,500 is plenty end game enough for me. Don’t own an HA-6A, but thinking about it in a year or so.
> 
> In my experience good tube amps are magic with high impedance dynamic driver headphones. At least with the amps I’ve listened to.
> 
> ...


To me the phenomenon you describe sounds like you only have experience with OTL tube amps. 

These generally have an impefance mismatch witj low impedance headphones and therefore sound off


----------



## skylinekursk

Gr3g277 said:


> You will be fine with either, the dc plate voltage is only a max rating on the datasheet.
> The 6l6wgc blackplate is one of my favorite tube for this amp.
> I have not tried the new red base version yet. If you get those I wish to know how they sound like


just ordered TAD 6550 backplates instead.... 6L6WGC in plan for next month I hope..


----------



## Andykong

Barnstormer13 said:


> $2,500 is plenty end game enough for me. Don’t own an HA-6A, but thinking about it in a year or so.
> 
> In my experience good tube amps are magic with high impedance dynamic driver headphones. At least with the amps I’ve listened to.
> 
> ...



Wander which tube amplifiers provides the observation to establish your working theory. can you share more information to clarify that?  Are they OTL tube amplifier or transformer coupled tube amplifier?


----------



## Barnstormer13

ThanatosVI said:


> To me the phenomenon you describe sounds like you only have experience with OTL tube amps.
> 
> These generally have an impefance mismatch witj low impedance headphones and therefore sound off


Sounds like it, but not true. As you can see in my signature, I currently have a SET amp and a hybrid amp. I have owned OTL amps in the past but prefer SETs because of their lower sensitivity to headphone impedance.  

The hybrid amp doesn’t match the SET for engagement, but it doesn’t roll off bass at low impedance, distort the bass at high current or get bloomy with moderate impedance dynamics.


----------



## Barnstormer13

Andykong said:


> Wander which tube amplifiers provides the observation to establish your working theory. can you share more information to clarify that?  Are they OTL tube amplifier or transformer coupled tube amplifier?



OTL: 
Bottlehead Crack (gone now): works great with 300 Ohm and higher phones.

SET: 
Woo WA-6SE (in my signature): an absolutely amazing sounding amp on headphones over 80 ohms. Starts to get underdamped (bloomy and wet)with dynamics below that.

DNA Starlet (listened to at friends house): Fantastic amp with a 3 ohm output impedance. It had no problem driving my Focal Clears which the Woo doesn’t handle as well. It wasn’t quite as good with my AFCs which are low impedance power pigs.


----------



## Fatdoi

ThanatosVI said:


> Totally agree here.
> It's very versatile indeed. For the American and Chinese price it offers killer Performance!
> Not so much in most european countries where it costs 50% more for no reason.
> 
> In the 2.5k range I can totally recommend it though.


If Cayin produced the 'perfect' HA6A for $2500 then who'd buy their $4000 HA300?


----------



## ThanatosVI (Apr 19, 2021)

Fatdoi said:


> If Cayin produced the 'perfect' HA6A for $2500 then who'd buy their $4000 HA300?


Those who prefer the sound of 300B tubes.


----------



## rmsanger (Apr 25, 2021)

... decided I’m interested in HA-300 instead


----------



## talmadge

Does anybody have any experience with the Focal Stellia and this amp?


----------



## skylinekursk

New tubes just been shipped to my door.. TAD 6550, Tung Sol 6L6GC, Genalex Gold Lion KT77 and 12au7 Tung Sol. 
6550 is not my type as it has good base and highs but mids are somewhere behind. 6lg6gc is better, sounds like el34 with better dynamics and more lows. Will see after few hours...


----------



## ThanatosVI

skylinekursk said:


> New tubes just been shipped to my door.. TAD 6550, Tung Sol 6L6GC, Genalex Gold Lion KT77 and 12au7 Tung Sol.
> 6550 is not my type as it has good base and highs but mids are somewhere behind. 6lg6gc is better, sounds like el34 with better dynamics and more lows. Will see after few hours...


I liked the Genalex Gold Lion 77, curious about your impressions.
Never heard the Tung Sol 12au7, but also interested in what you have to say about them


----------



## kimdeug (May 1, 2021)

talmadge said:


> Does anybody have any experience with the Focal Stellia and this amp?


I have Focal Elex, Radiance, Clear Pro and Celestee.  All of them sound exceptionally nice and beautiful on my HA-6A.
I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).
I am Sennh HD6XX, 660, 58X sound signature fan.
Love their intimate mid surround for jazz female vocals.
Have a lot of other headphones, but Focal's are my favorite now.
Using Tesla ECC802s with GEC KT88
Regards,
Kim


----------



## skylinekursk

kimdeug said:


> I have Focal Elex, Radiance, Clear Pro and Celestee.  All of them sound exceptionally nice and beautiful on my HA-6A.
> I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
> The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).
> I am Sennh HD6XX, 660, 58X sound signature fan.
> ...


Can any of these Focals play heavy music?


----------



## Magol79

kimdeug said:


> I have Focal Elex, Radiance, Clear Pro and Celestee.  All of them sound exceptionally nice and beautiful on my HA-6A.
> I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
> The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).
> I am Sennh HD6XX, 660, 58X sound signature fan.
> ...


How well does the Auteur match with the HA-6A in your opinion?


----------



## Fatdoi

kimdeug said:


> I have Focal Elex, Radiance, Clear Pro and Celestee.  All of them sound exceptionally nice and beautiful on my HA-6A.
> I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
> The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).
> I am Sennh HD6XX, 660, 58X sound signature fan.
> ...


Kim, when will you or have you got your hands on Utopia?


----------



## Fatdoi

Magol79 said:


> How well does the Auteur match with the HA-6A in your opinion?


all DD ZMFs pair well with tubes


----------



## Magol79

Fatdoi said:


> all DD ZMFs pair well with tubes


Yes, I know. But I want to know if the high power levels of the HA-6A over XLR is a good match for the Auteur. So far quite a few people have complained about hiss/noise on balanced out when pairing this amp with high impedance DD. 

I know that this is less of a problem over SE, but all my custom cables are XLR already and I would like to use them without an adapter.


----------



## talmadge (May 1, 2021)

kimdeug said:


> I have Focal Elex, Radiance, Clear Pro and Celestee.  All of them sound exceptionally nice and beautiful on my HA-6A.
> I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
> The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).
> I am Sennh HD6XX, 660, 58X sound signature fan.
> ...



So you don't have a problem with hiss or too high noise floor on the Focals? Enough range with the volume control? I have the Radiance also but probably gonna let it go since I got the Stellia. Great headphone though especially for the money.


----------



## 19844

Is my hifiman he1000 v2 will work properly with HA6A no hiss no hum? 

He1000 v2 spec Impedance : 35 Ohms Sensitivity : 90dB

Thank you


----------



## ThanatosVI

19844 said:


> Is my hifiman he1000 v2 will work properly with HA6A no hiss no hum?
> 
> He1000 v2 spec Impedance : 35 Ohms Sensitivity : 90dB
> 
> Thank you


Yes the He1000v2 will work perfectly fine


----------



## kimdeug (May 1, 2021)

skylinekursk said:


> Can any of these Focals play heavy music?


I dont listen a heavy music. Mostly instrumental jazz, blues, vocals. Electric Guitar and Bass solo.
For that purpose the Focal are very satisfying. But for complicated compositions, when a lot of instruments or sound effects are going at the same time, the planars can do much better this job. That is why I can see a lot of Audeze LCDX in the recording studios as well as Bero Dynamic 1990pro and 1770. So, in short: IMHO for heavy music the planars will do better than Focal's.


----------



## kimdeug

Magol79 said:


> How well does the Auteur match with the HA-6A in your opinion?


It is interesting feeling with Auteur on HA-6A. I like Auteur for it relaxing sound with all details. Not fatiguing for long listening session 6-8 hours.
But with HA-6A it becomes more energetic, more punchy. Of cause with all tube smoothness.  In opposite with Sennheiser HD800S it becomes more smooth, less treble, with more mids. In other words, on HA-6A Auteur is good for 2-3 hours, and after I prefer more darker headphone. In opposite with Solid state amplifiers i can listen Auteur for long session non stop. Regards, Kim


----------



## kimdeug (May 1, 2021)

Fatdoi said:


> Kim, when will you or have you got your hands on Utopia?


I have got Utopia (factory refurbished) for good price. But I don't like the sound. Too intense, no bass. Sounds like Elex with more treble.
Not worth this money. My expectation was much higher. My impression was exactly like "bad guy good review"  on youtube Utopia review.

And after 2 weeks (my luck) one driver died. I have done return and bought (from the same shop) both Celestee and Radiance  even for less money. Regards, Kim


----------



## kimdeug

talmadge said:


> So you don't have a problem with hiss or too high noise floor on the Focals? Enough range with the volume control? I have the Radiance also but probably gonna let it go since I got the Stellia. Great headphone though especially for the money.


This is a second HA-6A after the replacing the first one with hiss. This one does not have hiss with Focals.  Using Low impedance and 1/4 jack.


----------



## Gr3g277

kimdeug said:


> I have got Utopia (factory refurbished) for good price. But I don't like the sound. Too intense, no bass. Sounds like Elex with more treble.
> Not worth this money. My expectation was much higher. My impression was exactly like "bad guy good review"  on youtube Utopia review.
> 
> And after 2 weeks (my luck) one driver died. I have done return and bought (from the same shop) both Celestee and Radiance  even for less money. Regards, Kim



Ah too bad you didn't like them... seems to me like a faulty unit !

I use the utopia on my ha 6a with 1/4 cable and they sound great. With plenty of bass.
I also have a hifiman arya. And to my personal experience. The utopia sound more full bodied than the aryas !
Bass is even stronger. More impactful and very precise. Maybe a bit less extension below.
Treble is more refined. Midrange is less pronounced. Imaging and separation is on par with the arya. 
Soundstage is taller and wider with the hifiman. Focals are more intimate. But stage is deeper.
Also the sound is more dynamic or punchier !
I have yet to try the new clear mg . Wich is to me the most sexy looking headphone !

Would love also to try the abyss 1266 and the high end kennerton's.

Nowadays I am rocking 12bh7 as input and 6l6gc for power. And this combination is very silent.

I think we all hear differently, and we all post our impressions here , wich are very personal !
Always listen for yourself when you can


----------



## skylinekursk

hi gentlemen,
what resource of 22de4 tube? I'm curious because it's just few tubes on eBay and what if tube has just 1 000 hours life?...


----------



## ThanatosVI

skylinekursk said:


> hi gentlemen,
> what resource of 22de4 tube? I'm curious because it's just few tubes on eBay and what if tube has just 1 000 hours life?...


I'd ask Cayin directly since the 22de4 are no longer prodiced and only available as NOS


----------



## skylinekursk

ThanatosVI said:


> I'd ask Cayin directly since the 22de4 are no longer prodiced and only available as NOS


Cayin probably had to buy all tubes around the world! 😄 They are looks like new, I mean like new made tubes…


----------



## Newsee

kimdeug said:


> I think low impedance dynamic headphones have some magic with HA-6A.  That is why it always paired with Meze Imperian on all shows.
> The mids are so reach. This is what I was looking for long time from other  hi end headphones (including planars).


Hi Kim,

The Meze Empyrean is a planar  .
How you describe your preferences I think you would love it. Give it a try if you have not done it before.


----------



## kimdeug

Newsee said:


> Hi Kim,
> 
> The Meze Empyrean is a planar  .
> How you describe your preferences I think you would love it. Give it a try if you have not done it before.


I have tried Meze Empyrian (copper version). Not my type. Too neutral. Comfortable, good material quality, but but not my sound preference. And IMHO overpriced. Nothing special in sound and did not catch me to buy it. I had it around a week in my house, so had a good chance to listen it with all my gears and compare width my other headphones. If you realised, I have a lot of headphones, but not top of the range. Because, always try to justify the price/ performance ratio. The same happens to LCD4, Utopia, ZMF Verite. And somehow I don't like Hifiman brand at all ( may be because of loose quality).


----------



## kimdeug

ThanatosVI said:


> I'd ask Cayin directly since the 22de4 are no longer prodiced and only available as NOS


Good, let us know, please.
Only one source was available from Brazil on EBay. Sylvania 22DE4. But can not be shipped to New Zealand.


----------



## kimdeug

skylinekursk said:


> hi gentlemen,
> what resource of 22de4 tube? I'm curious because it's just few tubes on eBay and what if tube has just 1 000 hours life?...


Just have bought the last 12 NOS  Sylvania 22DE4 on Ebay from Brazil.


----------



## kimdeug (May 2, 2021)

Gr3g277 said:


> Ah too bad you didn't like them... seems to me like a faulty unit !
> 
> I use the utopia on my ha 6a with 1/4 cable and they sound great. With plenty of bass.
> I also have a hifiman arya. And to my personal experience. The utopia sound more full bodied than the aryas !
> ...


May be you are right. It was a refurbished unit with already replaced new drivers from Focal. And it fails again in 2 weeks,
I always want the Utopia. may be it is a bad luck.
But from another hand, I am fully in love with new Focal closed back Radiance and Celestee.
Looking to try Focal Stellia instead of Utopia.

Regards,
Kim


----------



## skylinekursk (May 2, 2021)

kt77 is amazing tube with plenty of lows and lush mids...I started use 12au7 by tung-sol and it has warm, full body character! Nice combo...
6550 is too "dry" for me, but it's also very very good tube with most powerful bass from all tube I have at the moment!
Will listen kt77 and 6l6gc more to get absolute winner..
p.s. funny thing..I asked seller for any other tubes but not kt77...he said try it, it's very interesting tube...he got me and I decided to get pair instead change =)


----------



## Gr3g277

skylinekursk said:


> kt77 is amazing tube with plenty of lows and lush mids...I started use 12au7 by tung-sol and it has warm, full body character! Nice combo...
> 6550 is too "dry" for me, but it's also very very good tube with most powerful bass from all tube I have at the moment!
> Will listen kt77 and 6l6gc more to get absolute winner..
> p.s. funny thing..I asked seller for any other tubes but not kt77...he said try it, it's very interesting tube...he got me and I decided to get pair instead change =)


Are those the gold lions kt77 ?
If yes they are very nice tubes indeed !
The kt77 is stated by a french tube expert called francis ibre, as the pinnacle of the el34 tube evolution !

I may try those in the future , now I am focusing on other aspects of my audio chain, especially on cleaning the usb from my computer, and experimenting with streamer devices.

enjoy the tubes !


----------



## rulerofrecords

So, it finally happened. Cayin Ha-6a ordered. Should be with me either end of the week or Monday. Was an offer I tried but failed to refuse ...


----------



## skylinekursk (May 4, 2021)

Gr3g277 said:


> Are those the gold lions kt77 ?
> If yes they are very nice tubes indeed !
> The kt77 is stated by a french tube expert called francis ibre, as the pinnacle of the el34 tube evolution !
> 
> ...


Thank you brother!
Yes, kt77 gold lions! These are winner of competition for el34 replacement for sure! 6L6gc is very good but kt77 more rich in harmonix..
so should I try more options from the manual like kt100, kt90, el37, 6ca7,  5881 and kt66?


----------



## ThanatosVI

skylinekursk said:


> Thank you brother!
> Yes, kt77 gold lions! These are winner of competition for el34 replacement for sure! 6L6gc is very good but kt77 more rich in harmonix..
> so should I try more options from the manual like kt100, kt90, el37, 6ca7,  5881 and kt66?


Cayin told me that they don't recommend kt100 ein though its in the Manual.
Imo just roĺl more KT88


----------



## ThanatosVI

rulerofrecords said:


> So, it finally happened. Cayin Ha-6a ordered. Should be with me either end of the week or Monday. Was an offer I tried but failed to refuse ...


Lemme guess, a used deal from Auditorium for ~2050?


----------



## skylinekursk

ThanatosVI said:


> Cayin told me that they don't recommend kt100 ein though its in the Manual.
> Imo just roĺl more KT88


Does kt88 from different brands has so much different sound? 😳


----------



## ThanatosVI

skylinekursk said:


> Does kt88 from different brands has so much different sound? 😳


Yes definitely!


----------



## skylinekursk

ThanatosVI said:


> Yes definitely!


Oh, great! What’s your favorite?


----------



## kimdeug (May 5, 2021)

skylinekursk said:


> Oh, great! What’s your favorite?


I have  KT88:  GEC, Genalex Golden Lion (made in England), Svetlana, Psvan MK-II and original Genalex (made in Russia).
GEC and Genalex (England made) are sound very reach, but the price is very painful.
Actually the original Genalex (made in Russia) are very good for their price.
I think, I will buy 5-7 pairs more of Genalex (Russia) for spares and will stick with them.
Also have ordered JJ Electronic KT88. But be careful with Chinese Replica one.
The original JJ Electronic KT88 made on old Tesla equipment and have more round bottle shape.
When the KT88 JJ Chinese replica have shorter and squared bottle shape and looks like Shuguang or Psvane KT88 tubes.
Regards, Kim


----------



## rulerofrecords

ThanatosVI said:


> Lemme guess, a used deal from Auditorium for ~2050?


you're good. But not that good , I managed to make the 1st digit a "1"! However - the experience of trying to get any information, feedback etc. from them is just a nightmare or not worth investing the time. On the other hand - the pure "mechanical" online process is just fine. What I'm trying to say is - I have no idea (condition, tubes, hiss, etc etc) what will show up here in a couple of days ...


----------



## ThanatosVI

rulerofrecords said:


> you're good. But not that good , I managed to make the 1st digit a "1"! However - the experience of trying to get any information, feedback etc. from them is just a nightmare or not worth investing the time. On the other hand - the pure "mechanical" online process is just fine. What I'm trying to say is - I have no idea (condition, tubes, hiss, etc etc) what will show up here in a couple of days ...


If it is the one from Auditorium,  chances are high that you receive my unit which is pretty much indistinguishable from a new one.
However the stock 12au7 in the right slot is noisy and you can hear a slight hiss on the right channel. This can be easily solved by rolling tubes.
Just in case it is my old one.

My experience with them Was purely on the phone and worked very well and fast.


----------



## kimdeug

Hey HA-6A lovers.
Try to order few 22DE4 tubes for spare stock collection (just in case). But can not find them as pair or big lot for sell.
Any links will be appreciated.
Regards, Kim


----------



## Zachik

kimdeug said:


> Actually the *original *Genalex (made in Russia) are very good for their price.


What do you mean by ORIGINAL?
Do you refer to those: https://www.thetubestore.com/genalex-gold-lion-kt88 ?



kimdeug said:


> I have KT88: GEC, Genalex Golden Lion (made in England), Svetlana, Psvan MK-II and original Genalex (made in Russia).


what are your impressions of the Psvane MK-II KT-88 tubes?


----------



## ThanatosVI

Zachik said:


> What do you mean by ORIGINAL?
> Do you refer to those: https://www.thetubestore.com/genalex-gold-lion-kt88 ?
> 
> 
> what are your impressions of the Psvane MK-II KT-88 tubes?


He refers to the Originals produced before 1980 (background Story in product description)

The offered product in the link are the reissues tho not the NOS tubes


----------



## Gr3g277

kimdeug said:


> Hey HA-6A lovers.
> Try to order few 22DE4 tubes for spare stock collection (just in case). But can not find them as pair or big lot for sell.
> Any links will be appreciated.
> Regards, Kim



Hello I bought a quad of Sylvania 22de4 from eBay for cheap, they appear to be exactly the same as the RCA originals.
No change in sound detected
they seems to be hard to find indeed, I don't see them very often, and there is no new production tubes to replace them, or suitable NOS replacement that I know of
I believe Cayin must have the world's supply of those tubes in house.

Any more information would be appreciated.


----------



## Andykong (May 5, 2021)

kimdeug said:


> Hey HA-6A lovers.
> Try to order few 22DE4 tubes for spare stock collection (just in case). But can not find them as pair or big lot for sell.
> Any links will be appreciated.
> Regards, Kim



Theoretically 22DE4 as rectifier tube has very long expected life span, they can easily last 3-5 years of regular use.    You don't need to have matched pair with 22DE4.  They are mean to isolate the power supply from each other, so each team is working independently, and they will age at different pace, so you can swap out one tube only instead of changing two tubes at the same time.


----------



## Zachik

ThanatosVI said:


> He refers to the Originals produced before 1980 (background Story in product description)
> 
> The offered product in the link are the reissues tho not the NOS tubes


Interesting - everything that is NOT reissue *that I can find* is made in the UK. Not Russian.


----------



## Gr3g277

skylinekursk said:


> Thank you brother!
> Yes, kt77 gold lions! These are winner of competition for el34 replacement for sure! 6L6gc is very good but kt77 more rich in harmonix..
> so should I try more options from the manual like kt100, kt90, el37, 6ca7,  5881 and kt66?


I think the kt66 may be worth a try as well, those are evolution from the 6l6 family.
Tung sols 7581A are also highly regarded....
So many options !
I also have tried the blackpkate kt88 from tad, they have super bass, and very linear and energetic sound, great for metal music ! 
( you should listen to the latest gojira album, it is great ! )


----------



## kimdeug (May 6, 2021)

Zachik said:


> What do you mean by ORIGINAL?
> Do you refer to those: https://www.thetubestore.com/genalex-gold-lion-kt88 ?
> 
> 
> what are your impressions of the Psvane MK-II KT-88 tubes?


Sorry for confusion. I was thinking by "original" the KT88 Genalex tubes, which came with HA-6A amplifier.
They are Russian made Genalex KT88, which I like a lot, so decided to buy 5-6 pairs and stay with them.
In opposite Genalex Gold Lion made in England or GEC are cost on eBay 1000$ for pair. I have one pair as Luxman pack (pictures somewhere above in this forum).
They sound fantastic, very similar as GEC KT88. More Dynamic, extended bass and juicy reach mids. Highs are so detailed, like you just heve swapped for Focal utopia headphone. IMHO KT88 GEC and Genalex (England) are the best, but very pricey. That's why I decided to stay with "original" ="russian" Genalex and do more experiments with 12AU7 tubes, as the range of last is huge. Regards, Kim


----------



## rulerofrecords

ThanatosVI said:


> If it is the one from Auditorium,  chances are high that you receive my unit which is pretty much indistinguishable from a new one.
> However the stock 12au7 in the right slot is noisy and you can hear a slight hiss on the right channel. This can be easily solved by rolling tubes.
> Just in case it is my old one.
> 
> My experience with them Was purely on the phone and worked very well and fast.


Well, it's a small world after all. Good to hear as I got nothing out of them. I have two pairs of 12Au7 waiting here (Sylvania and EI aka the "Jugolavian" Telefunken) so I'm curious if I can verify your observations on the infamous hiss topic. Again, cool ...


----------



## atya35mm

hi all, curious about the impedance setting you guys are on with your headphones. 

Is there a hard and fast rule i.e. the amp impedance must match the impedance of your headphones? I'm currently running on Susvara and using High Impedance to take advantage of as much power out of the amp even though the headphone is rated 60 ohms which to match I will have to use low impedance on the HA-6a. 

From my impressions, the key difference switching from low to high impedance is an improvement on the lower frequency and the slam / attack i.e. on certain tracks such as drum hits etc you can feel the bass instead of just hearing it. Mid / high frequency changes is not that apparent to me, but might be cleaner on the low impedance, but could also because I feel it's cleaner with lower bass. :/ So currently leaving on high impedance.


----------



## Gr3g277

atya35mm said:


> hi all, curious about the impedance setting you guys are on with your headphones.
> 
> Is there a hard and fast rule i.e. the amp impedance must match the impedance of your headphones? I'm currently running on Susvara and using High Impedance to take advantage of as much power out of the amp even though the headphone is rated 60 ohms which to match I will have to use low impedance on the HA-6a.
> 
> From my impressions, the key difference switching from low to high impedance is an improvement on the lower frequency and the slam / attack i.e. on certain tracks such as drum hits etc you can feel the bass instead of just hearing it. Mid / high frequency changes is not that apparent to me, but might be cleaner on the low impedance, but could also because I feel it's cleaner with lower bass. :/ So currently leaving on high impedance.


hello,

the rule of thumb about impedance matching for TUBE amps, is you should try to match the amp and transducer impedance to have optimal power transfer .

tubes being voltage amplification devices, they tend to be more powerful with higher impedances loads (  more Volts into more ohms for the same power )
Solid state devices are the other way around, they are Current amplification devices so they tend to be more efficient with lower impedance loads ( more amps into less Ohms, therefore less volts for the same power )

this is especially true for dynamic headphones, as they usually dont have a flat impedance curve, so the output impedance of the amp has it's importance
for planars, they are usually a straight line in impedance, so they shouldn't be affected as much sound wise by the output impedance of the amp.

If i remember correctly the output impedance are :
Low : 32-64ohm
mid : 64-300ohm
high: 150-600ohm

I would try the medium setting with your susvara. maybe the high Z is less controlled so the bass is bloomier ?
I wouldn't worry too much about it for you planar, it shouldn't have a big impact.
do you use the susvara balanced or single ended ?
with my aryas I use Balanced and Low impedance mode. If I go to High Z mode, it gets a bit louder, so my first impression is to think it is better, but if go back to low Z and give it 1 click more on the pot, loudness is the same again.

YMMV

On the other hand, I will take the example of my 80ohms utopia cans.
A lot of reviewers say they are thin in the bass... but they only ever listened to them on solid state amps with low output impedance.
when you look for the impedance graph : 






you can see a big jump to 300 ohms in the bass region.
So with a tube amp that can put out a lot of voltage, it means you have more power coming to the drivers at those frequencies.
Therefore the utopias sound a lot fuller.
I use them on the medium setting, and the difference with a SS amp is quite something ! now they are engaging !
High Z sounds great as well but I get too much hiss so I stick to mid.
Low Z sounds more like SS

here is your susvara for comparison




Seeing this graph, I would go mid Z, KT88, balanced out for max power.


----------



## atya35mm

Gr3g277 said:


> hello,
> 
> the rule of thumb about impedance matching for TUBE amps, is you should try to match the amp and transducer impedance to have optimal power transfer .
> 
> ...


Wow thanks for this, fantastic information! When I switched between low to medium impedance is when I noticed the most change now that you mentioned it, the switch from medium impedance to high impedance is quite minor, and I'm not sure whether it's an improvement or not, but stuck to high as from the power output table published by Cayin high impedance gives more power. But of course there is a relationship to the impedance of the headphone to determine final power output to headphone, which I don't quite know how to calculate. And yes I'm using balanced out. 

But will stick to medium now per your suggestion! Thanks @Gr3g277!!!!


----------



## rulerofrecords

ThanatosVI said:


> If it is the one from Auditorium,  chances are high that you receive my unit which is pretty much indistinguishable from a new one.
> However the stock 12au7 in the right slot is noisy and you can hear a slight hiss on the right channel. This can be easily solved by rolling tubes.
> Just in case it is my old one.
> 
> My experience with them Was purely on the phone and worked very well and fast.


Yes, it is most definitely your unit. The hiss in the right channel was exactly as described! And indeed tube rolling solved that issue and made the amp pretty much silent - at least with the two high impedance headphones I'm driving single ended. And thanx for taking good care of the amp. looks and feels new. Now back to getting used to that sledgehammer ...


----------



## ThanatosVI

rulerofrecords said:


> Yes, it is most definitely your unit. The hiss in the right channel was exactly as described! And indeed tube rolling solved that issue and made the amp pretty much silent - at least with the two high impedance headphones I'm driving single ended. And thanx for taking good care of the amp. looks and feels new. Now back to getting used to that sledgehammer ...


Enjoy, it is an amazing amp and I only gave it away because I had the opportunity to get my Octave V16 for cheap.


----------



## Andykong

atya35mm said:


> hi all, curious about the impedance setting you guys are on with your headphones.
> 
> Is there a hard and fast rule i.e. the amp impedance must match the impedance of your headphones? I'm currently running on Susvara and using High Impedance to take advantage of as much power out of the amp even though the headphone is rated 60 ohms which to match I will have to use low impedance on the HA-6a.
> 
> From my impressions, the key difference switching from low to high impedance is an improvement on the lower frequency and the slam / attack i.e. on certain tracks such as drum hits etc you can feel the bass instead of just hearing it. Mid / high frequency changes is not that apparent to me, but might be cleaner on the low impedance, but could also because I feel it's cleaner with lower bass. :/ So currently leaving on high impedance.



@Gr3g277 has provided a very good description of our impedance matching output feature, I just want to add one point to your case.  The Susvara is rated right in between the L and M impedance setting, so both setting is applicable to this headphone.  You can select either L or M impedance according to your preference.


----------



## Andykong

rulerofrecords said:


> Yes, it is most definitely your unit. The hiss in the right channel was exactly as described! And indeed tube rolling solved that issue and made the amp pretty much silent - at least with the two high impedance headphones I'm driving single ended. And thanx for taking good care of the amp. looks and feels new. Now back to getting used to that sledgehammer ...





ThanatosVI said:


> Enjoy, it is an amazing amp and I only gave it away because I had the opportunity to get my Octave V16 for cheap.



Wow, this is such a small world.   

@rulerofrecords I hope you'll enjoy your HA-6A, the headphone amp is very versatile, you can now expand your headphone collection with the peace of mind that your headphone amplifier will handle whatever you picked satisfactory, it might not be the best synergy pair possible, but it won't fall short.


----------



## rulerofrecords

Andykong said:


> Wow, this is such a small world.
> 
> @rulerofrecords I hope you'll enjoy your HA-6A, the headphone amp is very versatile, you can now expand your headphone collection with the peace of mind that your headphone amplifier will handle whatever you picked satisfactory, it might not be the best synergy pair possible, but it won't fall short.


Thanx Andykong, and I did notice you helping whenever and wherever you can while studying this thread. While I have your attention - you think this amp will drive an Hifiman HE6 properly - and secondly - do you have any experience with the EL37 as a EL34 replacement? cheers Uli


----------



## Andykong

rulerofrecords said:


> Thanx Andykong, and I did notice you helping whenever and wherever you can while studying this thread. While I have your attention - you think this amp will drive an Hifiman HE6 properly - and secondly - do you have any experience with the EL37 as a EL34 replacement? cheers Uli


Haven't try EL37 as EL34 replacement, but I have tried HE6 with HA-6A (KT88) in several time, it is powerful enough to handle the HE6 properly.  The sound signature is subject to personal preference, I like it very much.  It tame the harsh high frequency but didn't smooth it out completely, the bass is tight but the midrange is a slightly recessed.


----------



## 19844

Can I put Cayin HA-6A near my computer desktop and monitor? Can it be cause of hiss/hum or effect sound quality?


----------



## Gr3g277

19844 said:


> Can I put Cayin HA-6A near my computer desktop and monitor? Can it be cause of hiss/hum or effect sound quality?


yes, no problem, I have mine right next to my 32' monitor on the desk, no problems, and doesn't affect noise or sound .
Just be sure to leave a bit of room for air, as it can get fairly hot


----------



## Gr3g277

hey guys, 

Just to let you know, I have a burson soloist 3X Performance coming to me the next days... together with a gustard X26 Pro Dac, so I will be able to do some comparisons with the HA-6A 

I will have some stuff to write down in the next weeks, so stay tuned !
Also @Relaxasaurus I have seen your last video, and I would Have loved to come to your small meet up If I was in the NY region


----------



## Terriero (May 18, 2021)

Gr3g277 said:


> hey guys,
> 
> Just to let you know, I have a burson soloist 3X Performance coming to me the next days... together with a gustard X26 Pro Dac, so I will be able to do some comparisons with the HA-6A
> 
> ...


Would you share a link to the video (if it's not private or something like that)?. @FYFL commented to me about the meeting here, because I'm interested in renew my DAC an AMP and also looking for sinergy with different headphones. I took a look at this Cayin and maybe will be in my candidate listing... I will take a look at this thread 

*Edit*: I think I found the video you were referring (his last 2 minutes video with all the amps of the meet). The funny thing is that I found the @Relaxasaurus youtube channel yesterday, Youtube suggested to me one video of different amps comparison, I liked it a lot and inmediately suscribed to his channel


----------



## Andykong

19844 said:


> Can I put Cayin HA-6A near my computer desktop and monitor? Can it be cause of hiss/hum or effect sound quality?



Desktop computer and monitor normally didn't have any problem unless you use your computer as USB Audio source to your DAC, in that case, the USB cable from PC to DAC might introduce extra noise or hum into your audio system.   That's because the USB of your desktop computer shared the ground connection with keyboard, mouse, printer, ....etc etc.. You can refer to our previous discussion *HERE* regarding USB ground noise and vacuum tube amplifier.

Another source of noise is modem or WiFi connection,  IF you desktop is connected to a router at a distance through RJ45 cable, that should be fine.  If you have WiFi modem in the same room, that might be a problem too.


----------



## rulerofrecords

Okay, not so good news here. The amp went dead on me and went back to the dealer today who will then give it to his local tube service-guy (not Cayin-Service) - so this will take some time ...
However - maybe somebody can help here. What would be ideal/best fuses (type, designation) for the amp for potential future issue? I did change fuses but to no effect this time. Amp does start up, every tube is lighting up and the heating does work - but no signal is been output. A switch to my former amp with my desktop setup has confirmed - the Cayin is the problem. I heard from other people that this sounds 110% like "fuse blown" but it seems not to be the case here. There were some other issues (no, noise is not one of them) so I'm actually happy that the amp is being checked now. Unfortunately just one day after I had found the "perfect" tube-setup for me ;-(


----------



## ThanatosVI

rulerofrecords said:


> Okay, not so good news here. The amp went dead on me and went back to the dealer today who will then give it to his local tube service-guy (not Cayin-Service) - so this will take some time ...
> However - maybe somebody can help here. What would be ideal/best fuses (type, designation) for the amp for potential future issue? I did change fuses but to no effect this time. Amp does start up, every tube is lighting up and the heating does work - but no signal is been output. A switch to my former amp with my desktop setup has confirmed - the Cayin is the problem. I heard from other people that this sounds 110% like "fuse blown" but it seems not to be the case here. There were some other issues (no, noise is not one of them) so I'm actually happy that the amp is being checked now. Unfortunately just one day after I had found the "perfect" tube-setup for me ;-(


What was your tube setup in the end?


----------



## Andykong

rulerofrecords said:


> Okay, not so good news here. The amp went dead on me and went back to the dealer today who will then give it to his local tube service-guy (not Cayin-Service) - so this will take some time ...
> However - maybe somebody can help here. What would be ideal/best fuses (type, designation) for the amp for potential future issue? I did change fuses but to no effect this time. Amp does start up, every tube is lighting up and the heating does work - but no signal is been output. A switch to my former amp with my desktop setup has confirmed - the Cayin is the problem. I heard from other people that this sounds 110% like "fuse blown" but it seems not to be the case here. There were some other issues (no, noise is not one of them) so I'm actually happy that the amp is being checked now. Unfortunately just one day after I had found the "perfect" tube-setup for me ;-(



Did you change back to the factory default tubes?


----------



## Gr3g277

rulerofrecords said:


> Okay, not so good news here. The amp went dead on me and went back to the dealer today who will then give it to his local tube service-guy (not Cayin-Service) - so this will take some time ...
> However - maybe somebody can help here. What would be ideal/best fuses (type, designation) for the amp for potential future issue? I did change fuses but to no effect this time. Amp does start up, every tube is lighting up and the heating does work - but no signal is been output. A switch to my former amp with my desktop setup has confirmed - the Cayin is the problem. I heard from other people that this sounds 110% like "fuse blown" but it seems not to be the case here. There were some other issues (no, noise is not one of them) so I'm actually happy that the amp is being checked now. Unfortunately just one day after I had found the "perfect" tube-setup for me ;-(


Ouch too bad to hear this !

that sounds to me a lot like The HT fuse has blown up.

have you changed the fuse on the power supply board inside the amp ? ( not the one under the power cord )
for 220V it should be something like 250ma slo-blo, if I recall correctly ? maybe @Andykong can confirm 
I think you should have a spare one in the box with the documents 

let's hope it is only that !

did you try some tube rolling before the sound was gone ? which kind of tubes have you tried ?


----------



## kimdeug (May 19, 2021)

rulerofrecords said:


> Okay, not so good news here. The amp went dead on me and went back to the dealer today who will then give it to his local tube service-guy (not Cayin-Service) - so this will take some time ...
> However - maybe somebody can help here. What would be ideal/best fuses (type, designation) for the amp for potential future issue? I did change fuses but to no effect this time. Amp does start up, every tube is lighting up and the heating does work - but no signal is been output. A switch to my former amp with my desktop setup has confirmed - the Cayin is the problem. I heard from other people that this sounds 110% like "fuse blown" but it seems not to be the case here. There were some other issues (no, noise is not one of them) so I'm actually happy that the amp is being checked now. Unfortunately just one day after I had found the "perfect" tube-setup for me ;-(


From my understanding. If the tubes are glowing the fuse is ok. The problem is in signal path before the driver tubes or at amplifier tubes stage. May be simple contact disconnect in XLR to RCA switch button. Did you try XLR and RCA input? And also did you play with 6.3mm, 4.4 mm and XLR output button and connectors? Even without signal, did you hear the some extra noise On headphone when turn the volume up? If yes, so the amplifying stage is fine, means the signal is not coming  to the preamplifier/ driving tubes stage. Assuming you was in right headphone output and input (my guess)? Did you try to connect and disconnect RCA input at working amp with headphone in? You should hear the loud pop noise when disconnect or connect. For me it looks like wrong or faulty  connection issue. Regards, Kim


----------



## rulerofrecords

ThanatosVI said:


> What was your tube setup in the end?


EL37, RT6189, stock rectifier (GE rectifier hard to get in Europe)


----------



## rulerofrecords

Andykong said:


> Did you change back to the factory default tubes?


I did try a couple of settings before sending it in. I did not try the stock 12Au7 as one of those had already gone kinda bad on the previous owner Thanatos (he told me beforehand)


----------



## rulerofrecords

kimdeug said:


> From my understanding. If the tubes are glowing the fuse is ok. The problem is in signal path before the driver tubes or at amplifier tubes stage. May be simple contact disconnect in XLR to RCA switch button. Did you try XLR and RCA input? And also did you play with 6.3mm, 4.4 mm and XLR output button and connectors? Even without signal, did you hear the some extra noise On headphone when turn the volume up? If yes, so the amplifying stage is fine, means the signal is not coming  to the preamplifier/ driving tubes stage. Assuming you was in right headphone output and input (my guess)? Did you try to connect and disconnect RCA input at working amp with headphone in? You should hear the loud pop noise when disconnect or connect. For me it looks like wrong or faulty  connection issue. Regards, Kim


I did try most of that, RCA - XLR switch etc etc - what I did hear was a very slight hum. Yeah I'm not gonna speculate here. Only thing that does already bother me that the dealer I bought from is not sending the amp to Cayin in Germany for service - but to some "tube guy". I do not like that ...


----------



## rulerofrecords

Gr3g277 said:


> Ouch too bad to hear this !
> 
> that sounds to me a lot like The HT fuse has blown up.
> 
> ...


No did only change the fuses located at the power socket. Not sure which one of the two type of fuses provided was the right fuse to use here. Tried both to no effect. Hard to tell/see what the state of the individual fuse is, if it is really blown. I would never dare to get my hands on something like the supply board, or the entrails of a tube amp in the first place.  So now I'm not sure which fuse to place where - or which fuse to place at the power socket location???


----------



## ThanatosVI

rulerofrecords said:


> EL37, RT6189, stock rectifier (GE rectifier hard to get in Europe)


Are those direct replacements to the Standard tubes?
From a technical spec perspective?
Hopefully those aren't the source if the damage.


rulerofrecords said:


> I did try a couple of settings before sending it in. I did not try the stock 12Au7 as one of those had already gone kinda bad on the previous owner Thanatos (he told me beforehand)


Well it came like that from the dealer, but its not defect just a little noisy. So using that one would have been perfectly fine.


rulerofrecords said:


> I did try most of that, RCA - XLR switch etc etc - what I did hear was a very slight hum. Yeah I'm not gonna speculate here. Only thing that does already bother me that the dealer I bought from is not sending the amp to Cayin in Germany for service - but to some "tube guy". I do not like that ...


Well the "tube guy" makes sense.
Warranty is non transferable on Cayin products.

Therefore the dealer is responsible to provide you a working unit or refund your money, but he can't get it fixed from Cayin under warranty.
That means everything he is doing now, is on his own cost.
Also it might be better that way, if he would send it to Cayin it would take months until you receive it back.


----------



## Gizmo1k

does anyone have a copy of the manual in pdf? i'd prefer to have the manual to read electronically.


----------



## 19844

First day with cayin HA-6A I very like it. My came with JJ 12au7 no hiss with Hek2 triode and ultralinear Mode very useful


----------



## ThanatosVI

19844 said:


> First day with cayin HA-6A I very like it. My came with JJ 12au7 no hiss with Hek2 triode and ultralinear Mode very useful


Enjoy, it's a beautiful amplifier. 

I wonder how it compares to the McIntosh MHA200.


----------



## TeNeT

Hello, hope all are well!

I am new here. I am in search of a new HP amp, and after looking at many others; I have ended up on the HA-6A as top contender for my purchase!

I am interested in hearing how other owners feel about the amp. Especially if you have heard the Auris HA-2SF, which is my runner up. I wrote a preview (in a sense) based on what I read here (all 52 pages), on the Auris HA-2SF thread, and on manufacturers websites. 

https://www.head-fi.org/threads/auris-ha2-sf-vs-cayin-ha-6a.958117/

btw I really admire the owners here who stuck through the growing pains of this amp. You cleared the way for people like me! lol. 🙏


----------



## TeNeT

Gizmo1k said:


> does anyone have a copy of the manual in pdf? i'd prefer to have the manual to read electronically.


I looked for one online but they do not seem to have one for this model on site. They do have one for the HA-300.

I was wanting to look something up. Does anyone know; is it ok if you switch EL34/KT88 mode without switching tubes? Not that I really want to do that, but I am almost certain I will at some point, forget to switch it after changing tubes lol. Will it damage the amp if this happens?


----------



## Gr3g277

TeNeT said:


> I looked for one online but they do not seem to have one for this model on site. They do have one for the HA-300.
> 
> I was wanting to look something up. Does anyone know; is it ok if you switch EL34/KT88 mode without switching tubes? Not that I really want to do that, but I am almost certain I will at some point, forget to switch it after changing tubes lol. Will it damage the amp if this happens?


The amp will not explode if you forget don't worry 

the switch is for optimizing the operating points for the tube types, I don't know exactly what it does, but I speculate it is adjusting bias and maybe plate voltage.

that said, if you leave the switch on the kt88 position and put some el34 on, you may shorten the life of the tube by asking it too much.

so, yes better be careful, if you care about the life of your tubes, but it is not the end of the world if you forget to flip the switch for an hour.

ah yes, better flip the switch when the amp is turned off as well !


----------



## atya35mm

Quick one to the Empyrean owners out there, do you prefer to use XLR or the 1/4 inch output of the Cayin? I think it will be higher output from the XLR however the Empy isn't too hard to drive, so perhaps the 1/4 inch is better? Currently contemplating getting an Empyrean as my second headphone so keen to get your inputs.  

Thanks a million.


----------



## Andykong

atya35mm said:


> Quick one to the Empyrean owners out there, do you prefer to use XLR or the 1/4 inch output of the Cayin? I think it will be higher output from the XLR however the Empy isn't too hard to drive, so perhaps the 1/4 inch is better? Currently contemplating getting an Empyrean as my second headphone so keen to get your inputs.
> 
> Thanks a million.


It probably is related to music genre as well.  If you listen to a lot of vocal, with only one or two instruments in the background, single-ended connection will offer a more focused presentation, with the singer right in the middle of attention. If  you listen to symphony, live jazz band, or more complicated music with multiple instruments, the strength of channel separation will come into play and the balanced connection will work better. 

In addition, music that demands transient and control will be better off with balanced connection because of extra current, but if want to have an laid back and easy listening afternoon, use single-ended.

So balanced vs single-ended is  more then higher output power.  I think its worth getting both 6.35mm and XLR4 (or 4.4mm) cable when you acquire Empyrean.


----------



## atya35mm

Thanks Andy! I actually just received the Empyrean today, which came with single ended connection. Currently connecting directly to Dave and after one hour of listening and absolutely loving it. It might not have the perfect timbre, and bass is bit boomy etc but for casual listening while working it's so enjoyable. 

The channel separation like you said isn't as good when compared to Susvara connected to HA6A via XLR, but that's a different beast altogether, and I'll use that set up for more critical listening. 

Will try later tonight when I fired up the HA6A on the SE output, and be on the lookout for the XLR cable.


----------



## ThanatosVI

atya35mm said:


> Thanks Andy! I actually just received the Empyrean today, which came with single ended connection. Currently connecting directly to Dave and after one hour of listening and absolutely loving it. It might not have the perfect timbre, and bass is bit boomy etc but for casual listening while working it's so enjoyable.
> 
> The channel separation like you said isn't as good when compared to Susvara connected to HA6A via XLR, but that's a different beast altogether, and I'll use that set up for more critical listening.
> 
> Will try later tonight when I fired up the HA6A on the SE output, and be on the lookout for the XLR cable.


The "boomy bass" settles in with burn in and gets tighter.
It's still a slightly elevated bass but improves in quality with burn in


----------



## 19844

I have some noise from my PC by USB port it's silent when I use notebook as a source so I'm looking for streamer that work with HA-6A without noise. Can anyone recommend please?


----------



## atya35mm

ThanatosVI said:


> The "boomy bass" settles in with burn in and gets tighter.
> It's still a slightly elevated bass but improves in quality with burn in


Burn in might not be an issue as I got the Empyrean used, probably 2 years old. 

I said boomy, but maybe it's just the quantity of bass is a lot more compared to the Susvara setup, where it's tight and lean. I'm enjoying the different presentation to be honest, boomy or not at the end of the day it's just different and I like the variety since I listen anything from classical music, to acoustic jazz to EDMs. I'm beginning to see why some people here have >3 pairs of headphones, hopefully I'll stop at 2. 

Listening on the Cayin, my impression so far, when compared to the Susvara, I feel like listening to music on the Susvara is like experiencing a high end deconstructed desert, and it keeps on activating the analytical side of my brain especially when placement of vocals / instruments is so distinct and real and so easily separated. The Meze is just good old plain vanilla chocolate ice cream and reminds me of when I was enjoying music on a consumer headphone before getting into this hobby.


----------



## atya35mm

Andykong said:


> It probably is related to music genre as well.  If you listen to a lot of vocal, with only one or two instruments in the background, single-ended connection will offer a more focused presentation, with the singer right in the middle of attention. If  you listen to symphony, live jazz band, or more complicated music with multiple instruments, the strength of channel separation will come into play and the balanced connection will work better.
> 
> In addition, music that demands transient and control will be better off with balanced connection because of extra current, but if want to have an laid back and easy listening afternoon, use single-ended.
> 
> So balanced vs single-ended is  more then higher output power.  I think its worth getting both 6.35mm and XLR4 (or 4.4mm) cable when you acquire Empyrean.


@Andykong As I was using the single ended connection for the Empyrean, and switching around various modes i.e. UL / TR, and impedance settings, when I'm on UL mode, and flicking the impedance switch to low, there's a moderate high pitched tone coming into the headphone, not loud but moderate tone. 

Flicking the impedance to medium the tone stopped completely. Further experimenting, low impedance and TR mode is fine, as with other combinations. Just combination of UL and low impedance seem to have caused this issue. Is this something others experienced as well? 

FYI the amp is on EL34 tubes with the switch at the back on EL34 settings as well. Not overly concerned but thought I check as it's interesting.


----------



## ThanatosVI

atya35mm said:


> @Andykong As I was using the single ended connection for the Empyrean, and switching around various modes i.e. UL / TR, and impedance settings, when I'm on UL mode, and flicking the impedance switch to low, there's a moderate high pitched tone coming into the headphone, not loud but moderate tone.
> 
> Flicking the impedance to medium the tone stopped completely. Further experimenting, low impedance and TR mode is fine, as with other combinations. Just combination of UL and low impedance seem to have caused this issue. Is this something others experienced as well?
> 
> FYI the amp is on EL34 tubes with the switch at the back on EL34 settings as well. Not overly concerned but thought I check as it's interesting.


I never experienced this, back then when I had my Ha-6a


----------



## ThanatosVI

atya35mm said:


> Burn in might not be an issue as I got the Empyrean used, probably 2 years old.
> 
> I said boomy, but maybe it's just the quantity of bass is a lot more compared to the Susvara setup, where it's tight and lean. I'm enjoying the different presentation to be honest, boomy or not at the end of the day it's just different and I like the variety since I listen anything from classical music, to acoustic jazz to EDMs. I'm beginning to see why some people here have >3 pairs of headphones, hopefully I'll stop at 2.
> 
> Listening on the Cayin, my impression so far, when compared to the Susvara, I feel like listening to music on the Susvara is like experiencing a high end deconstructed desert, and it keeps on activating the analytical side of my brain especially when placement of vocals / instruments is so distinct and real and so easily separated. The Meze is just good old plain vanilla chocolate ice cream and reminds me of when I was enjoying music on a consumer headphone before getting into this hobby.


Yeah then it's probably just the amount of bass.

New Empyreans Show a noteable improvement in the first 50h, more than most other Headphones I experienced. 
That's why I considered it worth mentioning.
In your case it probably doesn't apply anymore


----------



## Newsee

atya35mm said:


> Burn in might not be an issue as I got the Empyrean used, probably 2 years old.
> 
> I said boomy, but maybe it's just the quantity of bass is a lot more compared to the Susvara setup, where it's tight and lean. I'm enjoying the different presentation to be honest, boomy or not at the end of the day it's just different and I like the variety since I listen anything from classical music, to acoustic jazz to EDMs. I'm beginning to see why some people here have >3 pairs of headphones, hopefully I'll stop at 2.
> 
> Listening on the Cayin, my impression so far, when compared to the Susvara, I feel like listening to music on the Susvara is like experiencing a high end deconstructed desert, and it keeps on activating the analytical side of my brain especially when placement of vocals / instruments is so distinct and real and so easily separated. The Meze is just good old plain vanilla chocolate ice cream and reminds me of when I was enjoying music on a consumer headphone before getting into this hobby.


When I listened first to Susvara I felt it was so airy that I was missing the body  from the music .
Could you please explain a bit more in detail what is a "high end deconstructed desert"? I like the expression, but difficult to imagine.
Btw. welcome to the Empy club!


----------



## atya35mm

A quick google to get this picture of a deconstructed chocolate hazelnut cake, as opposed to just good ol’ chocolate hazelnut cake. Haha.


----------



## Fatdoi

Andykong said:


> It probably is related to music genre as well.  If you listen to a lot of vocal, with only one or two instruments in the background, single-ended connection will offer a more focused presentation, with the singer right in the middle of attention. If  you listen to symphony, live jazz band, or more complicated music with multiple instruments, the strength of channel separation will come into play and the balanced connection will work better.
> 
> In addition, music that demands transient and control will be better off with balanced connection because of extra current, but if want to have an laid back and easy listening afternoon, use single-ended.
> 
> So balanced vs single-ended is  more then higher output power.  I think its worth getting both 6.35mm and XLR4 (or 4.4mm) cable when you acquire Empyrean.


Hi Andy,

So will the input of RCA vs XLR affect the output power of SE & XLR?


----------



## Andykong

Fatdoi said:


> Hi Andy,
> 
> So will the input of RCA vs XLR affect the output power of SE & XLR?


 RCA or XLR input does not affect the rated output power of HA-6A


----------



## atya35mm

I just recently purchased a second hand power cable (PS audio AC-5 cable), it's not expensive so thought I do an experiment, and the result is quite a noticeable improvement from the stock power cable. So for those still using the stock cable, might be worth getting an aftermarket one if you haven't yet.


----------



## Loftprojection

I’m looking for opinion on the stepped volume control of the HA-6A with Empyrean combination?  I’m quite picky on volume adjustment so I usually shy away from stepped but some implementation are ok.  Any of you guys can share your thoughts on this combo?  Many thanks.


----------



## 19844

Can anyone please compare gold Lion KT77 with gold Lion KT88?


----------



## ThanatosVI

19844 said:


> Can anyone please compare gold Lion KT77 with gold Lion KT88?


The Gold Lion  KT88 have better extension on both ends.
Better subbass and air up top. 

The Gold Lion KT77 have the sweeter midrange in return.


----------



## 19844

ThanatosVI said:


> The Gold Lion  KT88 have better extension on both ends.
> Better subbass and air up top.
> 
> The Gold Lion KT77 have the sweeter midrange in return.


Thank you


----------



## Adogsbestfriend32

atya35mm said:


> @Andykong As I was using the single ended connection for the Empyrean, and switching around various modes i.e. UL / TR, and impedance settings, when I'm on UL mode, and flicking the impedance switch to low, there's a moderate high pitched tone coming into the headphone, not loud but moderate tone.
> 
> Flicking the impedance to medium the tone stopped completely. Further experimenting, low impedance and TR mode is fine, as with other combinations. Just combination of UL and low impedance seem to have caused this issue. Is this something others experienced as well?
> 
> FYI the amp is on EL34 tubes with the switch at the back on EL34 settings as well. Not overly concerned but thought I check as it's interesting.


I had a similar issue to this on my HA 6A. Had a similar high pitched tone on my verite closed headphones. It was slightly better on single ended and using a preamp before the HA 6A. I figured it was an impedance matching issue. I ended up getting an impedance adapter made by a friend and no longer have this issue.


----------



## atya35mm

Adogsbestfriend32 said:


> I had a similar issue to this on my HA 6A. Had a similar high pitched tone on my verite closed headphones. It was slightly better on single ended and using a preamp before the HA 6A. I figured it was an impedance matching issue. I ended up getting an impedance adapter made by a friend and no longer have this issue.


Hi, one thing that quickly resolves it as well is just changing to other EL34 tubes. I was using Shuguang 6ca7z, and it seems to be the only tubes that had this issue using low and UL setting. Switching back to stock EL34 and there's no problem.


----------



## therock10

anybody have experience with it. does it pair well with focal utopia?


----------



## Adogsbestfriend32

atya35mm said:


> Hi, one thing that quickly resolves it as well is just changing to other EL34 tubes. I was using Shuguang 6ca7z, and it seems to be the only tubes that had this issue using low and UL setting. Switching back to stock EL34 and there's no problem.


Hmm I noticed it on stock and other el34 tubes.


----------



## Yoram Diamand

19844 said:


> I have some noise from my PC by USB port it's silent when I use notebook as a source so I'm looking for streamer that work with HA-6A without noise. Can anyone recommend please?


https://sotm-usa.com/products/sms-200-neo-network-player I will buy this one special edition with silver wire


----------



## Yoram Diamand

Yoram Diamand said:


> https://sotm-usa.com/products/sms-200-neo-network-player I will buy this one special edition with silver wire


For an usb dac like the ayre qb 9, only the transport


----------



## Andykong

Adogsbestfriend32 said:


> I had a similar issue to this on my HA 6A. Had a similar high pitched tone on my verite closed headphones. It was slightly better on single ended and using a preamp before the HA 6A. I figured it was an impedance matching issue. I ended up getting an impedance adapter made by a friend and no longer have this issue.





Adogsbestfriend32 said:


> Hmm I noticed it on stock and other el34 tubes.



But the problem only occur with 300ohm ZMF headphones at low impedance setting, and you won't encounter similar problem with low impedance headphones at the same impedance setting, maybe it is an impedance mismatch problem.


----------



## Andykong

19844 said:


> I have some noise from my PC by USB port it's silent when I use notebook as a source so I'm looking for streamer that work with HA-6A without noise. Can anyone recommend please?



Have you tried adding an isolator between the PC and DAC? Something like iFi iGalvanic3.0 USB might solve your problem.

Alternatively, look for streamer or digital transport with coaxial or AES/EBU output. This will get rid of USB Audio in your music chain completely, and in many cases, offer a very silent background in your system.
​


----------



## kyorakun

Hi guys

I'm looking at the Ha-6A to drive my susvaras. I'm currently using a denafrips hyperion power amp but am unsure if the HA-6A can drive my cans. Anyone have any experiences with HA-6A + susvara? Would really appreciate some feedback. Thanks!


----------



## Adogsbestfriend32

kyorakun said:


> Hi guys
> 
> I'm looking at the Ha-6A to drive my susvaras. I'm currently using a denafrips hyperion power amp but am unsure if the HA-6A can drive my cans. Anyone have any experiences with HA-6A + susvara? Would really appreciate some feedback. Thanks!


Yes can confirm. I use it with my susvara
And 1266 and it drives them wonderfully.


----------



## kyorakun

Adogsbestfriend32 said:


> Yes can confirm. I use it with my susvara
> And 1266 and it drives them wonderfully.


Hi

How is the bass impact with the ha-6a and what tubes do you use them with? Thanks for the reply.


----------



## Tsunzo

Anyone knows a good site to buy replacement 22DE4 tubes? I was also wondering if they need to be matched for the rectifier. I am hearing hum and hiss on mine and I want to try to replace them to see if it fixes the problem.


----------



## Yoram Diamand

Tsunzo said:


> Anyone knows a good site to buy replacement 22DE4 tubes? I was also wondering if they need to be matched for the rectifier. I am hearing hum and hiss on mine and I want to try to replace them to see if it fixes the problem.


http://vacuumtubesuperstore.com/22de4.html


----------



## Yoram Diamand

Yoram Diamand said:


> http://vacuumtubesuperstore.com/22de4.html


I do not know this adress but they have a lot


----------



## Tsunzo

Yoram Diamand said:


> http://vacuumtubesuperstore.com/22de4.html


Thanks, Do you know if they need to be matched?


----------



## Adogsbestfriend32

kyorakun said:


> Hi
> 
> How is the bass impact with the ha-6a and what tubes do you use them with? Thanks for the reply.


Bass impact is definitely a little more on solid state power amp however not by much. The ha 6a drives the really well and the trade offs are well worth it. The kt88 generally give more bass impact while the el34 sound more natural over all. I use winged c svetlana el34 and the telefunken new kt88. Then I switch between Sylvania 22de4 and ge both nos. The pre amp tubes (12au7) I have a pair of super rare pinched waist ones.


----------



## Andykong

Tsunzo said:


> Thanks, Do you know if they need to be matched?



No, they don't.  One of the main purpose of the rectifying circuit is to isolate the power supply circuitry into independent sections and minimise interference from each other, so they rectifier tubes are supposed to be independent from each other, hence they don't need to be matched.


----------



## 19844

Tsunzo said:


> Anyone knows a good site to buy replacement 22DE4 tubes? I was also wondering if they need to be matched for the rectifier. I am hearing hum and hiss on mine and I want to try to replace them to see if it fixes the problem.



In my case noise/hiss happened to me when I use PC as a source when I use streamer noise/hiss disappear but not sure about your case.


----------



## Tsunzo

19844 said:


> In my case noise/hiss happened to me when I use PC as a source when I use streamer noise/hiss disappear but not sure about your case.


I haven't tried with different sources other than my pc> bifrost 2 > cayin HA-6A. But with my other headphones the noise wasn't that bad at all until I tried it with a zmf verite.


----------



## Andykong

Tsunzo said:


> I haven't tried with different sources other than my pc> bifrost 2 > cayin HA-6A. But with my other headphones the noise wasn't that bad at all until I tried it with a zmf verite.



What is the impedance setting?  Mid or Low with other headphones but High with Verite?


----------



## Tsunzo

I mostly used my Diana v2 when I still had it on med settings with no background hiss and hum currently I am using my verite on high settings I notice there’s less background noise on med settings but not by much


----------



## Andykong

Tsunzo said:


> I mostly used my Diana v2 when I still had it on med settings with no background hiss and hum currently I am using my verite on high settings I notice there’s less background noise on med settings but not by much




You are connecting Verite to HA6A is XLR4/4.4mm? Do you happen to have a 6.35mm cable to try Vertis in single-ended?


----------



## Tsunzo

I have tried with all xlr, 4.4mm and 6.3mm all has background noise with the verite.


----------



## Andykong

Tsunzo said:


> I have tried with all xlr, 4.4mm and 6.3mm all has background noise with the verite.



Form what I guess, your sound system has somehow picked up small amount of interference. 

The Diana v2 is rated at 91dB sensitivity, and if you driving it with KT88, Ultralinear, Mid Impedance, BAL, the output of HA-6A in this condition is 27.39V.
The Verite is rated at 99dB sensitivity, and if you driving it with KT88, Ultralinear, *High* Impedance, BAL, the output of HA-6A in this condition is 51.96V.

In other word, you are using a headphone that is 8dB more sensitive, with 1.9x more powerful amplification.  That explained why can't hear any noise with Diana v2, but you can hear it with Verite.  Even with single-ended 6.35mm, the output (46.48V) is significantly more powerful than Mid impedance significantly.

To solve the problem, you need to eliminate or minimise the interference which is the source of the noise.  It can be wireless devices in the same room, or dirty switching power supply or heavy duty appliance in the same power supply circuit (same circuit breaker), unshielded interconnect, ...

For the record, I have used HD800 with HA-6A in many shows and public demo, it doesn't have noticeable noise, and  the HD800 is very similar to Verite in both impedance and sensitivity.


----------



## Tsunzo

Andykong said:


> Form what I guess, your sound system has somehow picked up small amount of interference.
> 
> The Diana v2 is rated at 91dB sensitivity, and if you driving it with KT88, Ultralinear, Mid Impedance, BAL, the output of HA-6A in this condition is 27.39V.
> The Verite is rated at 99dB sensitivity, and if you driving it with KT88, Ultralinear, *High* Impedance, BAL, the output of HA-6A in this condition is 51.96V.
> ...


Thanks for the useful information, I would have to figure out where the source of the noise by eliminating them one by one. It will probably take some time lol


----------



## tinariwen

Hey guys,

I've just picked up a used ha-6a, and the sound is incredible. I'm driving a pair of ZMF VCs, and previously was using a Schiit Lyr 3. I didn't really think an amp could have that much impact on sound, but wow. It's so much more visceral.

I've got a couple questions, though. Luckily there's almost no noise on the medium impedance setting, but there is on high. Not enough to detract from the music - I can only really hear it between tracks. It sounds more like the typical background hum of tubes, to be honest.

I've read through chunks of this thread, but does anyone have any recommendations for tube rolling that they've found improved the background noise? I saw that the amp is now sold with JJ tubes - are they a big improvement?

Also, one or some of the tubes is incredibly microphonic. To the point where, if I lightly tap my finger nail on the front of the chassis, or even drag my headphone cable along it, you can clearly hear it. There's also some pings and clicks for the first 20mins of use, which sounds a lot like an old radiator warming up (for want of a better description).

I think it's one of the KT88 tubes, but it's difficult to be sure. Has anyone else had a similar amount of microphonics, and if so, what did you change to fix it?

I'm gonna keep reading through the thread in the meantime, but if anyone can shed any light before I get through it I'd really appreciate it.

Cheers!


----------



## Tsunzo

I have changed out all of the tubes to testif the static noise will disappear but it's still the same, noise still present with my zmf VO. Using all quality interconnects, usb and even with a power purifier.


----------



## Fatdoi

Tsunzo said:


> I have changed out all of the tubes to testif the static noise will disappear but it's still the same, noise still present with my zmf VO. Using all quality interconnects, usb and even with a power purifier.


what is your source equipment?


----------



## Tsunzo

Fatdoi said:


> what is your source equipment?


Desktop pc>bi-frost2>Ha-6a


----------



## Fatdoi

Tsunzo said:


> Desktop pc>bi-frost2>Ha-6a


have you tried plug the amp from a cd player?


----------



## Tsunzo

Fatdoi said:


> have you tried plug the amp from a cd player?


Yes I have tried to use my m11 dap via 4.4mm to xlr into the ha6a the noise is still there. It’s a static noise that’s inconsistent and comes and goes sometimes louder sometimes quiet.


----------



## Fatdoi

Tsunzo said:


> Yes I have tried to use my m11 dap via 4.4mm to xlr into the ha6a the noise is still there. It’s a static noise that’s inconsistent and comes and goes sometimes louder sometimes quiet.


well my last suggestion is to try SE input instead of XLR.... if it still got noise then i'm out of ideas.....
damn i've been monitoring this amp since its announcement and many users had issue with noise which keeping me on the fence on this one as i've been searching for years for a OT tube amp for ZMF cans.....


----------



## Tsunzo

Fatdoi said:


> well my last suggestion is to try SE input instead of XLR.... if it still got noise then i'm out of ideas.....
> damn i've been monitoring this amp since its announcement and many users had issue with noise which keeping me on the fence on this one as i've been searching for years for a OT tube amp for ZMF cans.....


Yea.. I’ve even tried it with nothing plugged into the input and noise is still there. This seem to only happen with my dynamic driver headphones strangely. I previously had a Diana v2 and there wasn’t any static noises using that.


----------



## Gr3g277

Tsunzo said:


> Yea.. I’ve even tried it with nothing plugged into the input and noise is still there. This seem to only happen with my dynamic driver headphones strangely. I previously had a Diana v2 and there wasn’t any static noises using that.


what kind of input tubes did you try ?

Sounds like you're having bad luck with noisy tubes...
also try to go single ended out instead of balanced, and low or medium impedance setting.
this will reduce the noise greatly;

balanced will be perfect with no noise with low sensitivity headphones ( like your dianav2) (91db sensitivity )
for example with focals (104db sensitivity ) it is better to use single ended

for the verite at 99db, I would stick to single ended, high or medium impedance, don't worry too much about the setting, juste use the one that does not bother you, there is plenty power on tap, even with the lowest setting....

if there is is still noise, maybe swap the input tube for nos sylvania 6189 or 5814
New production JJ or eh gold are not bad for noise.
I would avoid shuguang or psvane 12au7, I had bad luck with those...

your bifrost 2 shouldn't be a problem, I have it as well, and the usb connection is galvanicly isolated, so it cannot induce ground loop.


----------



## Tsunzo

Gr3g277 said:


> what kind of input tubes did you try ?
> 
> Sounds like you're having bad luck with noisy tubes...
> also try to go single ended out instead of balanced, and low or medium impedance setting.
> ...


I am currently using nos sylvania 6189 tubes and other than that ive only had the stock ones. I have not tried using this with single ended only balanced I think thats the next thing I am going to try! Thanks!


----------



## munce31

Hi all,

Has it been determined that there is no alternative to the 22de4 rectification tubes, which can be used with the Ha-6a?

Im just concerned with how relatively difficult they are to source, when compared to other rectification tubes.


----------



## ungauged

munce31 said:


> Hi all,
> 
> Has it been determined that there is no alternative to the 22de4 rectification tubes, which can be used with the Ha-6a?
> 
> Im just concerned with how relatively difficult they are to source, when compared to other rectification tubes.


Long time lurker here, curious about this as well. Seems I am unable to find any info or tubes in the event it needs replacement.


----------



## Andykong

munce31 said:


> Hi all,
> 
> Has it been determined that there is no alternative to the 22de4 rectification tubes, which can be used with the Ha-6a?
> 
> Im just concerned with how relatively difficult they are to source, when compared to other rectification tubes.



I was under the impression that 22DE4 is not difficult to acquire, but there aren't any alternate option available so it is difficult to conduct tube rolling.

As mentioned previously, Cayin HA-6A uses two pieces of 22DE4 for power rectification.  It is important to know that they are used in two separated, independent power circuit and their main purpose was to provide as much isolation as possible to each other.   So please don't treat them as a pair.  You can replace only one 22DE4 at a time, and there is no need to look for matched pair.  

Rectification tubes convert AC top DC and are not involved in amplification or signal control.  In our experience rectification tubes are very long lasting.   10,000+ hours is a common reference point, and we have seen speaker amplifiers with rectification tube that had been used for 10 years and still operative.  You can understand more about rectification tube from HERE, HERE and HERE.


----------



## ThanatosVI

Andykong said:


> I was under the impression that 22DE4 is not difficult to acquire, but there aren't any alternate option available so it is difficult to conduct tube rolling.
> 
> As mentioned previously, Cayin HA-6A uses two pieces of 22DE4 for power rectification.  It is important to know that they are used in two separated, independent power circuit and their main purpose was to provide as much isolation as possible to each other.   So please don't treat them as a pair.  You can replace only one 22DE4 at a time, and there is no need to look for matched pair.
> 
> Rectification tubes convert AC top DC and are not involved in amplification or signal control.  In our experience rectification tubes are very long lasting.   10,000+ hours is a common reference point, and we have seen speaker amplifiers with rectification tube that had been used for 10 years and still operative.  You can understand more about rectification tube from HERE, HERE and HERE.


Actually thr 22DE4 seems to be quite hard to aquire in my country. None of my trusted stores have it and in case of replacement need I'd have to ask Cayin Support directly.


----------



## Andykong

ThanatosVI said:


> Actually thr 22DE4 seems to be quite hard to aquire in my country. None of my trusted stores have it and in case of replacement need I'd have to ask Cayin Support directly.



I didn't aware about that, I was only looking at the English speaking locations in the past.  I just conduct a search in eBay and located two 22DE4 listing in Continental Europe (HERE and HERE), but you are correct, most 22DE4 listing are US based.


----------



## No Disc (Sep 13, 2021)

Are there supply issues for the Cayin HA-6A?  I am trying to purchase one locally in China and the dealer told me the company is having difficulty getting parts for this unit? The dealer could not tell me when I could get one.

@Andykong


----------



## Andykong

No Disc said:


> Are there supply issues for the Cayin HA-6A?  I am trying to purchase one locally in China and the dealer told me the company is having difficulty getting parts for this unit? The dealer could not tell me when I could get one.
> 
> @Andykong



You have posted the same message on HA1Amk2 and HA6A thread.  I am surprised that you are buying two completely different tube amplifier at the same time.

I am not familiar with the dealer network in China, so please contact our Sales Manger john@cayin.cn, he'll put you in touch with the nearest dealer who carry these amplifiers.


----------



## kimdeug

ThanatosVI said:


> Actually thr 22DE4 seems to be quite hard to aquire in my country. None of my trusted stores have it and in case of replacement need I'd have to ask Cayin Support directly.


Currently on sale 22DE4:

https://www.ebay.com/itm/142500018580?hash=item212da9b994:g:1Q4AAOSwXvNZsRX3


----------



## tinariwen

Has anyone listened to both the Feliks Euforia and Cayin ha-6a?

I'm wondering how they compare, and there's nowhere nearby for me to hear a Euforia.


----------



## kimdeug

ThanatosVI said:


> Actually thr 22DE4 seems to be quite hard to aquire in my country. None of my trusted stores have it and in case of replacement need I'd have to ask Cayin Support directly.


It is true.
Nowadays, it is very hard to find 22DE4 in NOS NIB condition, but it is still possible. I was searching for this tubes last 6 months all around the world (Canada, Japan, Brazil, Poland, Russia, Australia etc) and I am from New Zealand, where the tube stock is absolutely limited. As result of 6 month search is a picture of my tube collection below.
Everything is possible my friend, do not give up. 

Regards,
Kim


----------



## 19844

I very like verite with cayin HA-6A using 6.3mm unbalanced no any hiss until volume at 3Oclock


----------



## tinariwen

19844 said:


> I very like verite with cayin HA-6A using 6.3mm unbalanced no any hiss until volume at 3Oclock


Is it new, or did you buy it second hand? Also, what tubes are you using?

I bought a used one not long back and managed to reduce the hiss to an expected level for tubes by rolling, but it's still present. Interestingly it doesn't change at all based on volume position.


----------



## 19844

tinariwen said:


> Is it new, or did you buy it second hand? Also, what tubes are you using?
> 
> I bought a used one not long back and managed to reduce the hiss to an expected level for tubes by rolling, but it's still present. Interestingly it doesn't change at all based on volume position.


Its a new one it come with 12au7 JJ tube. first I got hiss when I use my PC as a source then I try with streamer all hiss disappear with my hifiman he1000se but Verite I hear hiss only volume at 3Oclock or more.


----------



## kimdeug (Sep 19, 2021)

19844 said:


> Its a new one it come with 12au7 JJ tube. first I got hiss when I use my PC as a source then I try with streamer all hiss disappear with my hifiman he1000se but Verite I hear hiss only volume at 3Oclock or more.


It is normal (acceptable for me) hiss. After replacement of my unit, it arrived with JJ 12AU7 tubes. And it was exactly like you said with my ZMF Auteur hiss was after 3 oclock, but in my situation on only in XLR output and high impedance position. 1/4 was quiet in all impedance position. I have done some tube rolling 12AU7, switched to RCA input (XLR -too much gain), as a source switched from PC to laptop Apple MB Pro15 (less USB ground interference), used Ifi USB signal cleaner, DAC Cambridge Audio 851D and now it is dead silent.
BTW: I am using now Tesla ECC802S and KT88 Gold Lion UK made


----------



## tinariwen

kimdeug said:


> It is normal (acceptable for me) hiss. After replacement of my unit, it arrived with JJ 12AU7 tubes. And it was exactly like you said with my ZMF Auteur hiss was after 3 oclock, but in my situation on only in XLR output and high impedance position. 1/4 was quiet in all impedance position. I have done some tube rolling 12AU7, switched to RCA input (XLR -too much gain), as a source switched from PC to laptop Apple MB Pro15 (less USB ground interference), used Ifi USB signal cleaner, DAC Cambridge Audio 851D and now it is dead silent.
> BTW: I am using now Tesla ECC802S and KT88 Gold Lion UK made


When you say 'acceptable hiss' and '1/4 was quiet in all impedance position', do you mean you can still hear hiss, but it's quiet enough to be acceptable? I'm trying to understand if your amp is actually dead silent, or that it's quiet enough for you to accept the typical tube hiss


----------



## kimdeug

tinariwen said:


> When you say 'acceptable hiss' and '1/4 was quiet in all impedance position', do you mean you can still hear hiss, but it's quiet enough to be acceptable? I'm trying to understand if your amp is actually dead silent, or that it's quiet enough for you to accept the typical tube hiss


We are talking about replaced unit which came with JJ12AU7 tube. The first unit was with very loud hiss and humm, so I have returned it and have got a replacement (6months after )). The replaced unit came with no any hiss/humm on 1/4 out at all impedance position. In XLR output hiss only starts on high impedance and volume 3 o'clock. I have used ZMF Auteur and HD800s balanced XLR and 4.4 balanced cables. After tube rolling, switched to laptop, USB signal filtering and better DAC, even this hiss (after 3 o'clock on high impedance and XLR output ) is gone. Now it is very quiet, even I turn my volume on max without any music. Regards, Kim 
PS, doing all this different setups I have found that Cayin HA-6A is very sensitive to USB quality signal, wi fi and some other interferences when you place it close to computer case, or near wi fi station, or even when mouse or keyboards cable cross the DAC USB cable.


----------



## kimdeug (Sep 20, 2021)

tinariwen said:


> When you say 'acceptable hiss' and '1/4 was quiet in all impedance position', do you mean you can still hear hiss, but it's quiet enough to be acceptable? I'm trying to understand if your amp is actually dead silent, or that it's quiet enough for you to accept the typical tube hiss


Small life hack. To understand in my case, where the hiss was coming from I made a simple experiment. Took a paper box. Big enough to cover all HA 6A and tall enough to give a space to remove the heat from tubes. After I have covered this box from inside and outside by aluminium food foil. Simply say: made a double shielded box cover. And after listen music covering with box and without. That is how I found that external factors are giving me a hiss after 3 o'clock. On balanced output ,high impedance setting. Not sure what was exactly, but this double shielded box test helps me a lot. So, sharing my trick here. Regards, Kim


----------



## tinariwen

kimdeug said:


> Small life hack. To understand in my case, where the hiss was coming from I made a simple experiment. Took a paper box. Big enough to cover all HA 6A and tall enough to give a space to remove the heat from tubes. After I have covered this box from inside and outside by aluminium food foil. Simply say: made a double shielded box cover. And after listen music covering with box and without. That is how I found that external factors are giving me a hiss after 3 o'clock. On balanced output ,high impedance setting. Not sure what was exactly, but this double shielded box test helps me a lot. So, sharing my trick here. Regards, Kim


I think mine is one of the first batch, as there is some hum / hiss when in high impedance, but nothing that I can hear over music.

The worst part is there is random, intermittent 'static' that appears in the right channel. It doesn't seem to be tube dependant as I've changed tubes and swapped them left to right, and it's always on the right side. It sounds like muffled static.

Do you have any ideas what could cause it? I've moved the amp to a different room and it still has the same problem. I've tried different sources and even tried different RCA cables, too.


----------



## tinariwen

Hey all,

I posted yesterday about an odd static noise coming from the right channel of my Cayin ha-6a amp.  Oddly enough, I managed to reduce the problem quite a bit by trying some different NOS tubes, but then things went downhill pretty quickly.  Now I've got no sound coming through my headphones apart from a low hum.  D'oh!

I wanted to try a couple of 'accessories' I thought might help reduce some of the background hiss when no music is playing.  First, I changed the power cable to an Audioquest NRG Y3, which made no noticeable difference, regardless of whether music was playing or not.  I then added two Audiocrast XLR Noise Stopper Caps to the XLR inputs on the rear of the amp, and again, no noticeable difference.

I then decided to switch back to the original power cable and remove the XLR Noise Stopper Caps (for a comparison).  When I turned the amp on, no noise was coming from my headphones except for a low hum.  I've removed and reinserted the tubes, changed the tubes entirely for different ones, changed the RCA source cable, and tried a different power cable.  I've also tried a different source, tried different headphones, and tried a different headphone cable.  The amp will power on, the tubes will heat up, but there is nothing but a low hum coming from the headphones.

I then noticed that the VU meters weren't registering any sound, despite music being played.  Could the XLR Noise Stoppers or the power cable somehow damaged the input section of the amp?  If so, what is likely to be the fault, and is it something that a local repair shop could fix?  Unfortunately I have no warranty, so I'm looking to repair the amp locally.

Any advice or suggestions would be really appreciated.


----------



## Andykong

tinariwen said:


> Hey all,
> 
> I posted yesterday about an odd static noise coming from the right channel of my Cayin ha-6a amp.  Oddly enough, I managed to reduce the problem quite a bit by trying some different NOS tubes, but then things went downhill pretty quickly.  Now I've got no sound coming through my headphones apart from a low hum.  D'oh!
> 
> ...



Please check PM, I have send you some questions, hopefully that will help us to shortlist  your problem.

By the way, coming Friday is the National Day of the People's Republic of China and the country will celebrate over a one week period. The 7-day holiday begins from October 1st and runs until the 7th.  I'll check the forum regularly but I won't have any support from our Engineer during this period.


----------



## robyzfi

I'm selling mine. It is currently at Cayin Germany.

https://cayin.com/produkt/cayin-ha-6a_röhren-kopfhörerverstärker/


----------



## kimdeug

robyzfi said:


> I'm selling mine. It is currently at Cayin Germany.
> 
> https://cayin.com/produkt/cayin-ha-6a_röhren-kopfhörerverstärker/


What is the reason? Something new is coming?


----------



## robyzfi

Same reason as yours. I have one from the first batch. Perfect with the Empyrean, too much noise floor with the Verite Open (I didn't try to use the high impedance setting).

Cayin Germany offered me to apply the same modifications done in newer units. I'm evaluating if I can get something else.


----------



## tinariwen

So I managed to fix the problem - somehow the fuse had blown inside (t160 I think).

The really interesting thing is that, after replacing that fuse, the noise floor has dropped dramatically (same tubes). It's practically inaudible, except for perhaps a ground loop hum as it's near my work desk and shares the plugs with a lot of other devices.

So, for anyone having a problem with the noise floor, try replacing the fuse. It's a 2min job, and the spares come in the box. It might not fix anything for you, but it's a very cheap and easy fix if it does.


----------



## kimdeug

tinariwen said:


> So I managed to fix the problem - somehow the fuse had blown inside (t160 I think).
> 
> The really interesting thing is that, after replacing that fuse, the noise floor has dropped dramatically (same tubes). It's practically inaudible, except for perhaps a ground loop hum as it's near my work desk and shares the plugs with a lot of other devices.
> 
> So, for anyone having a problem with the noise floor, try replacing the fuse. It's a 2min job, and the spares come in the box. It might not fix anything for you, but it's a very cheap and easy fix if it does.


Thanks for sharing.  Good to know. Will do experiments with some very high quality audio fuses.


----------



## tinariwen

kimdeug said:


> Thanks for sharing.  Good to know. Will do experiments with some very high quality audio fuses.


Let me know how you get on. I won't be changing anything for a while as I don't want to rock the boat, but it'll be good to know what fuses you find work best


----------



## ThanatosVI

Andy shared this picture in the Ha300 thread. 

Thought I'd post it here since there is also a Black Ha-6A on the horizon. 

Not sure if it's just the color or a Mk2 Kind of deal.

If it's Mk2 I'd really hope for Support up to KT170


----------



## Andykong

tinariwen said:


> So I managed to fix the problem - somehow the fuse had blown inside (t160 I think).
> 
> The really interesting thing is that, after replacing that fuse, the noise floor has dropped dramatically (same tubes). It's practically inaudible, except for perhaps a ground loop hum as it's near my work desk and shares the plugs with a lot of other devices.
> 
> So, for anyone having a problem with the noise floor, try replacing the fuse. It's a 2min job, and the spares come in the box. It might not fix anything for you, but it's a very cheap and easy fix if it does.



Thank you for  your update.  Glad you fixed the problem, so its the 300B High voltage fuse after all.  Interesting part is, if the fuse had blown, you should have a defeated channel , instead of noise or lower volume output in a particular channel.   This sure has gone beyond my previous observations and I'll definitely recommend users to check the internal fuse whenever they run into similar problem.


----------



## Andykong

ThanatosVI said:


> Andy shared this picture in the Ha300 thread.
> 
> Thought I'd post it here since there is also a Black Ha-6A on the horizon.
> 
> ...



Thank you for sharing the photo.

Unfortunately, we don't have a HA-6A MK2 in our development plan, and we don't have any plan to use KT150 or KT170 in our tube headphone amplifier in foreseeable future.


----------



## hongthaie

Tube amp bring warm sound, I like detail and clear


----------



## ThanatosVI

hongthaie said:


> Tube amp bring warm sound, I like detail and clear


That depends on the amp and tubes used.


----------



## krude (Oct 15, 2021)

I've got my HA6a for a few months now and decided to share my thoughts.

TL;DR I love it 

a bit longer bit ... I use it with Utopia (for listening) and HD800 (for playing guitar), I mostly listen to hard and dynamic music, metal, rock, electronica, but also soundtracks, acoustic and bits of classical now and then, and for dynamic music it knocks it out of the park with Utopia. I use Holo May L2 as source, but tried it with Hugo 2 and it was still really good.

All 3 impedance settings are amazing, triode mode and UL are amazing, the slam, the punch, the smoothness, the bass ... drum impact, staging ...

It was a bit noisy at first but now after it (and tubes) burned in (use it with stock tubes in KT88 mode) it is pretty silent (for a tube amp).

Anyway, Utopia and HA6a is one of those pairings that blows my socks off every time I fire it up.


----------



## Parnracing

I got my HA-6A three days ago. come with JJ 12au7

I use it with Beyer DT1990 . 
i found HIZZ noise from 1/4 on minimal volume. more found in UL mode
I test on Unplug everything. No any inputs. Only Power cable.

what should i do


----------



## kimdeug

Parnracing said:


> I got my HA-6A three days ago. come with JJ 12au7
> 
> I use it with Beyer DT1990 .
> i found HIZZ noise from 1/4 on minimal volume. more found in UL mode
> ...


1. Try to do paper box test, I have described last page. To eliminate the ambient interference.
2. Try to roll 12AU7 tubes.
3. Give around 100 hours burning time.
4. Check the supply power and cable. 

Regards,
Kim


----------



## ThanatosVI

kimdeug said:


> 1. Try to do paper box test, I have described last page. To eliminate the ambient interference.
> 2. Try to roll 12AU7 tubes.
> 3. Give around 100 hours burning time.
> 4. Check the supply power and cable.
> ...


The Ha-6a does look gorgeous. 
Those are socket savers on your 12au7 right?


----------



## kimdeug

ThanatosVI said:


> The Ha-6a does look gorgeous.
> Those are socket savers on your 12au7 right?


Yes. They are socket savers. Because a lot of 12Au7 tubes have more thicker pins.
Socket savers:  https://www.aliexpress.com/item/1005003234451973.html?spm=a2g0o.cart.0.0.2eaa3c00bQWQTk&mp=1
Aluminium rings: https://www.aliexpress.com/item/4000012197427.html?spm=a2g0o.cart.0.0.2eaa3c00bQWQTk&mp=1

I have contacted to Poland Miltra manufacture to buy only 2 aluminium rings for my Cayin HA-6A.
Lets see:  https://www.miltra.pl/index.php/produkt/headphone-tube-amplifier-miltra-otl-pcl86/


----------



## Parnracing

today i just got Arya.

hiss noies has disappeared.

I think my dt1990 have 109db is  very sensitive with tube amps


----------



## kimdeug

Parnracing said:


> today i just got Arya.
> 
> hiss noies has disappeared.
> 
> I think my dt1990 have 109db is  very sensitive with tube amps


I am using my DT1990 pro with Cayin HA-6A now. Middle impedance, 1/4 jack, volume 9 o'clock. No hiss at all. No music, volume at 3 o'clock -- I can hear the tubes humm, but very little and it can be neglected. At real usage situation I never go above 9 o'clock.


----------



## kimdeug (Oct 20, 2021)

tinariwen said:


> Let me know how you get on. I won't be changing anything for a while as I don't want to rock the boat, but it'll be good to know what fuses you find work best



I am very skeptical about this upgrade.
Just have few Aliexpress vouchers to burn before 11.11
Lets see, what is this hype about.
Have ordered these fuses:
https://www.aliexpress.com/item/1005002559074708.html?spm=a2g0o.detail.1000014.13.4aca7afdM0volt&gps-id=pcDetailBottomMoreOtherSeller&scm=1007.13338.183347.0&scm_id=1007.13338.183347.0&scm-url=1007.13338.183347.0&pvid=ebabe69b-d581-4139-bf26-b5e85f6f1d51&_t=gps-idcDetailBottomMoreOtherSeller,scm-url:1007.13338.183347.0,pvid:ebabe69b-d581-4139-bf26-b5e85f6f1d51,tpp_buckets:668#2846#8109#1935&&pdp_ext_f={"sceneId":"23416","sku_id":"12000021138642122"}

Regards,
Kim


----------



## Parnracing

Hifiman Arya
If I use the middle gain, will there be a problem with the headphones or the amp?


----------



## kimdeug

Parnracing said:


> Hifiman Arya
> If I use the middle gain, will there be a problem with the headphones or the amp?


Not for amp, but for headphone it is not good. It is designed for optimal impedance 41Ohms. Better to use it on low impedance setup. If you put too big impedance you will burn/ damage the wire coil on magnet drivers.


----------



## Lapinata

Hi, I am totally a newbie to this hobby, never had any tube amp before. After spending hours on this forum I decided to purchase HA-6A. It has been 20 days of usage, burning period probably completed 

So far I am in love with it. I do hear the hissing like many of you, but it is less noticeable when playing the music. Start hearing it when turning volume more than 10 o'clock, when reaching 2 o'clock it becomes unbearable (I will never reach that anyway, just do for the sake of testing)
*Test with Beyerdynamic DT990 Pro - Medium - 6.3 output*

Overall, I am pretty content with what I get from this unit. I decided to stick with EL34 because of its sweetness. Now, I'm aiming for the sound that gives me more diabetes. XD Willing to upgrade both *JJ 12AU7* and *EH EL34*. Gold pin 12AU7 is very attractive to me.
Any recommendations ?? I would love to see the comparison between each brand as well since I am new here. 
Oh...and the budget would be around $150 for each pair


----------



## kimdeug (Nov 3, 2021)

Lapinata said:


> Hi, I am totally a newbie to this hobby, never had any tube amp before. After spending hours on this forum I decided to purchase HA-6A. It has been 20 days of usage, burning period probably completed
> 
> So far I am in love with it. I do hear the hissing like many of you, but it is less noticeable when playing the music. Start hearing it when turning volume more than 10 o'clock, when reaching 2 o'clock it becomes unbearable (I will never reach that anyway, just do for the sake of testing)
> *Test with Beyerdynamic DT990 Pro - Medium - 6.3 output*
> ...


Congrats. If you like sweet sound try the Sylvania 12AU7 NOS, They are very cheap around 10$ each green print. British made tubes Mullard, Brimar and CV.4003... not sure as do not remember the number are also sweet and soft. Do not be fullished by gold pins, like reissued JJ or ElectroHarmonics or Genalex or chinees Psvan gold pins tubes. They are looking nice, but is it all about the sound? I am listening with Tesla ECC802S now, and they are so close to 10 times expensive Telefunken E82CC. Regards, Kim

PS, for EL34 rolling try Reissued Russian Genalex KT77 tubes.


----------



## Whitigir

El34 ? Try Mullard XF2
12AU7 ? Try RCA clear plate NOS ?


----------



## keysmebaby

I have Meze Elite & ifi ZEN DAC v2. If I buy HA-6A, can I use it well?


----------



## KerrangZ

keysmebaby said:


> I have Meze Elite & ifi ZEN DAC v2. If I buy HA-6A, can I use it well?


Keen to know this too. Have the Elite as well..


----------



## kimdeug

keysmebaby said:


> I have Meze Elite & ifi ZEN DAC v2. If I buy HA-6A, can I use it well?


It will synergise beautifully. That is why in all exebitions and shows the HA-6A was mostly paired with Meze Imperian. Zen Dac is a Dac, so will work as suppose to work.


----------



## ThanatosVI

keysmebaby said:


> I have Meze Elite & ifi ZEN DAC v2. If I buy HA-6A, can I use it well?





KerrangZ said:


> Keen to know this too. Have the Elite as well..


Ha-6a synergizes beautifully with the Meze Headphones. 
No idea about the ZEN DAC v2 tho.


----------



## kimdeug

Lapinata said:


> Hi, I am totally a newbie to this hobby, never had any tube amp before. After spending hours on this forum I decided to purchase HA-6A. It has been 20 days of usage, burning period probably completed
> 
> So far I am in love with it. I do hear the hissing like many of you, but it is less noticeable when playing the music. Start hearing it when turning volume more than 10 o'clock, when reaching 2 o'clock it becomes unbearable (I will never reach that anyway, just do for the sake of testing)
> *Test with Beyerdynamic DT990 Pro - Medium - 6.3 output*
> ...


Some 12AU7 tube info


----------



## Lapinata

kimdeug said:


> Some 12AU7 tube info


Wow, very appreciate for more info. 
I was doing my research for all this time as well. I decided to get a pair of *Amperex 12AU7* (used) as a newbie step (i guess haha) 
I just got them few hours ago.

Short Review:
Compare to the stock tube JJ 12AU7/ECC82, Amperex pair is more ‘FUN’. They bring extension to all ranges. The impact on *Low* is punchier (still very clean, just nice) *Mids* somewhat upfront even in TR mode, but also sweeter. *Highs* are smoother, brass instrument  is giving me eargasm.


----------



## kimdeug (Nov 13, 2021)

Lapinata said:


> Wow, very appreciate for more info.
> I was doing my research for all this time as well. I decided to get a pair of *Amperex 12AU7* (used) as a newbie step (i guess haha)
> I just got them few hours ago.
> 
> ...


Thanks for sharing and nice photos. Good tube choice. Amperex sounds very reach and juicy and you have got a nice model with long black plate and big O jetter. Yours one even more better as it is made not in Holland, it is made in US. Very solid choice for NEWBIER )
If you are really like EL34 tube sound, I recommend to try reissued Russian Genalex KT77 tubes, they are quite cheap 70 USD each, but the most mids sweet sounding tubes.
I am listening a lot of female and instrumental jazz and blues music. So my preference is KT88 tubes. More impact and extension like 3D effect. Looking to roll with Telefunken EL156 with adapters in the future, but currently quite happy with russian Genalex, GEC and Gold Lion UK made tubes as Luxman package (photo was in this forum before)
 I am planning a big tube rolling day with 12AU7 tubes, will post my impression here. Regards, Kim


----------



## Whitigir

I have 12AU7 NOS RCA Clear or normal plate, and it is even more detailed and transparent than my 12AU7 Sylvania


----------



## Lapinata

kimdeug said:


> Thanks for sharing and nice photos. Good tube choice. Amperex sounds very reach and juicy and you have got a nice model with long black plate and big O jetter. Yours one even more better as it is made not in Holland, it is made in US. Very solid choice for NEWBIER )
> If you are really like EL34 tube sound, I recommend to try reissued Russian Genalex KT77 tubes, they are quite cheap 70 USD each, but the most mids sweet sounding tubes.
> I am listening a lot of female and instrumental jazz and blues music. So my preference is KT88 tubes. More impact and extension like 3D effect. Looking to roll with Telefunken EL156 with adapters in the future, but currently quite happy with russian Genalex, GEC and Gold Lion UK made tubes as Luxman package (photo was in this forum before)
> I am planning a big tube rolling day with 12AU7 tubes, will post my impression here. Regards, Kim


Even more Wowwww for me.
Btw, these are made in Holland, the printing wear off a lot.

I really want to roll both 12au7 and el34 at the same time, but i don’t want to hurt my pocket continuously   Genalex KT77 is already in my cart only waiting for me to trigger.


----------



## kimdeug (Nov 13, 2021)

Lapinata said:


> Even more Wowwww for me.
> Btw, these are made in Holland, the printing wear off a lot.
> 
> I really want to roll both 12au7 and el34 at the same time, but i don’t want to hurt my pocket continuously   Genalex KT77 is already in my cart only waiting for me to trigger.


Tube made in Holland Amperex factory does not have R in circle after Amperex. My Amperex 12AU7 is made in West Germany. May be yours made in Holland Phillips miniwat factory, I can see a white print on top of the tubes.


----------



## Lapinata

Whitigir said:


> I have 12AU7 NOS RCA Clear or normal plate, and it is even more detailed and transparent than my 12AU7 Sylvania


I shall add this to my next rolling list, thanks for the recommendation



kimdeug said:


> Tube made in Holland Amperex factory does not have R in circle after Amperex. My Amperex 12AU7 is made in West Germany. May be yours made in Holland Phillips miniwat factory, I can see a white print on top of the tubes.


It is really made in Holland, not sure if you can notice from the photo. Printing on both tubes are really faded. 
And Yes, both tubes got white print on top of them.


----------



## kimdeug

Recently it is very quiet here.
So, few pictures of my updated setup to keep the interest to this forum.


----------



## ThanatosVI

Good news, the official price of the Cayin Ha-6a got finally reduced in germany.
From ridiculous 3500€ to 3000€
Finally more in line with the other amps that are available for 2500$, like the McIntosh MHA200 (also 3000€ in germany)

Interestingly it's now cheaper than the Feliks Euforia AE which received a price increase.


----------



## rulerofrecords

ThanatosVI said:


> Good news, the official price of the Cayin Ha-6a got finally reduced in germany.
> From ridiculous 3500€ to 3000€
> Finally more in line with the other amps that are available for 2500$, like the McIntosh MHA200 (also 3000€ in germany)
> 
> Interestingly it's now cheaper than the Feliks Euforia AE which received a price increase.


I think the guys in the UK had/have it worse regarding HA-6a and HA300 - any info if they get a little lucky, too?


----------



## ThanatosVI

rulerofrecords said:


> I think the guys in the UK had/have it worse regarding HA-6a and HA300 - any info if they get a little lucky, too?


Unfortunately I don't know


----------



## dvmrp (Nov 29, 2021)

Hi, I have been using this for a few days. Initially there was hum on all outputs and gain settings, it was fixed by removing the hdmi connection to my Pioneer LX800. I still can hear very subtle current sound on the middle level gain of XLR output. Other than this, others are quiet enough.

I do have a question want to hear experience from you guys. I am using HD800 via XLR output. The source is LX800->XLR->HA-6A. It is loud enough even with volume knob at between 8 - 10 o'clock and low gain. Is it normal?


----------



## rulerofrecords

dvmrp said:


> Hi, I have been using this for a few days. Initially there was hum on all outputs and gain settings, it was fixed by removing the hdmi connection to my Pioneer LX800. I still can hear very subtle current sound on the middle level gain of XLR output. Other than this, others are quiet enough.
> 
> I do have a question want to hear experience from you guys. I am using HD800 via XLR output. The source is LX800->XLR->HA-6A. It is loud enough even with volume knob at between 8 - 10 o'clock and low gain. Is it normal?


It would mostly depend on what you personally consider "loud enough". Other than that - yes, with the HD-800 I often listen around the 9-11 o'clock mark as well with my setup ...


----------



## Andykong

dvmrp said:


> Hi, I have been using this for a few days. Initially there was hum on all outputs and gain settings, it was fixed by removing the hdmi connection to my Pioneer LX800. I still can hear very subtle current sound on the middle level gain of XLR output. Other than this, others are quiet enough.
> 
> I do have a question want to hear experience from you guys. I am using HD800 via XLR output. The source is LX800->XLR->HA-6A. It is loud enough even with volume knob at between 8 - 10 o'clock and low gain. Is it normal?



Glad to know you have solved the hum noise problem to a larger extend.  The HDMI cable is connected between your LX800 and TV? or between LX800 with an AV amplifier?  Wonder where is the source of the hum noise, did you connect any USB peripheral to your TV or AV amplifier?

For the record, like most tube amplifier, the HA-6A didn't has a gain control feature. The HA-6A has three stages of amplification: 12AU7, KT88/EL34, and output transformer. None of these amplification stages can adjust "gain ratio" like a solid state amplifier, so unless we include a solid state amplification stage in the circuit (and the HA-6A become a hybrid amplifier instead of a tube amplifier), we can't offer gain control as a lot of users have anticipated.

The H/M/L switch select the corresponding impedance matching outputs from the output transformer, they were designed to improve the handling against different impedance loading. We have listed the impedance in the specification.  L: 8~64Ω; M: 65~250Ω; and H: 251~600Ω.  Be reminded that these conducted in analogue domain, they are not exact science like 0 and 1, so if your headphone are rated at 50Ω, you can try both L and M and determine which one sounds better to your ears.  But if you were using 24Ω or 32Ω, that L is probably your most likely choice.


----------



## dvmrp

Andykong said:


> Glad to know you have solved the hum noise problem to a larger extend.  The HDMI cable is connected between your LX800 and TV? or between LX800 with an AV amplifier?  Wonder where is the source of the hum noise, did you connect any USB peripheral to your TV or AV amplifier?
> 
> For the record, like most tube amplifier, the HA-6A didn't has a gain control feature. The HA-6A has three stages of amplification: 12AU7, KT88/EL34, and output transformer. None of these amplification stages can adjust "gain ratio" like a solid state amplifier, so unless we include a solid state amplification stage in the circuit (and the HA-6A become a hybrid amplifier instead of a tube amplifier), we can't offer gain control as a lot of users have anticipated.
> 
> The H/M/L switch select the corresponding impedance matching outputs from the output transformer, they were designed to improve the handling against different impedance loading. We have listed the impedance in the specification.  L: 8~64Ω; M: 65~250Ω; and H: 251~600Ω.  Be reminded that these conducted in analogue domain, they are not exact science like 0 and 1, so if your headphone are rated at 50Ω, you can try both L and M and determine which one sounds better to your ears.  But if you were using 24Ω or 32Ω, that L is probably your most likely choice.


Hi, it is the HDMI cable to a Samsung TV. BTW, I eventually can turn on H, and volume knob at 12-1pm by connecting the old AKG K-1000. This amp is really capable.


----------



## Lapinata

kimdeug said:


> *White Noise Test*
> 
> Hello  Cayin HA-6A lovers.
> 
> ...


I stumbled upon Krell Cable on Black Friday Sales. I was like I saw this cable somewhere.....and finally, I found that it is from here. 

How is your opinion of getting this cable? Is there any upgrade regarding audio quality? I only power HA-6A through the wall without a power conditioner.


----------



## kimdeug (Dec 1, 2021)

Lapinata said:


> I stumbled upon Krell Cable on Black Friday Sales. I was like I saw this cable somewhere.....and finally, I found that it is from here.
> 
> How is your opinion of getting this cable? Is there any upgrade regarding audio quality? I only power HA-6A through the wall without a power conditioner.


love it so much. Bought 10 more on 11.11 sale. Not sure about improve the sound, but aesthetically and shielded design are definitely pleasing my eyes and biasing my ears too.
 Link: https://www.aliexpress.com/item/4000164163717.html?spm=a2g0s.9042311.0.0.45944c4dFolAU9

This one is better as slightly lighter.
The Cryo series is more heavier and stiffer. I have bought 20A sockets and converted them into the monoblock amps supply cables.


----------



## Marutks

rulerofrecords said:


> I think the guys in the UK had/have it worse regarding HA-6a and HA300 - any info if they get a little lucky, too?



HA-6a costs around 3000 gbp here


----------



## rulerofrecords

Marutks said:


> HA-6a costs around 3000 gbp here


that is a solid 3500 Euros. Hefty!


----------



## Lapinata

I was free, so I had the idea of “tubes in the dark” popped up to my mind. Just took one to add to the forum gallery.
……Might do KT88 later


----------



## dvmrp

Hi, is it possible to connect the 4.4mm balanced outputs of a portable headphone DAC to the RCA input via a 4.4mm_2_RCA cable? Will it damage the amp or the DAC? Thanks for the reply.


----------



## ArkNerevar

Hello everyone, after a considerable amount of research and contemplation/consideration of alternatives, I made the plunge from solid state to tube and now have a Cayin HA-6A! yay, I do however have a serious problem with my using it for which I'm now seeking some help. 

When connected in my normal chain as Deezer HIFI/PC > silver plated USB > BRZHIFI DDC (digital to digital converter/clocker) > silver plated AES > XD05-Bal (BRZHIFI external linear power supply) functioning as DAC through aux port > silver plated 3.5-2RCA > HA-6A > ZMF stock OFC balanced cable > ZMF Verite open, I constantly have an electrical noise coming through the phones, sounds most like an old dial up modem, first thing I tried was to disconnect the AES cable and connect my phone to the DAC via USB, no electrical noise, with that I just hear the background hum that everyone here talks about, the one that is worst when on high impedance/UL mode, the to be expected HA-6A hum. 

This indicates that the problem was coming from the PC, the amp itself was not faulty (background hum aside), a relief to be sure but I was still left with a serious use problem, before anyone says "just use your phone or streamer as the source then" I use my PC for everything this includes not just my music streaming but also video and much more importantly games, I'm a hardcore gamer (& proud of it) a big part of getting the HA-6A was for my games, so a streamer is not an option, I need my PC in the chain. With that said I have tried a few things to see what I could do about the noise, I changed the USB cable (from the PC) and tried them in different sockets, I changed the AES cable and tried a coaxial cable (from the DDC) I replaced the DAC with a schitt modi 3 connected with pure silver RCA cables to the amp and I changed the amps power cord, initially it shared the same strip the PC is plugged into, I tried on a second strip from the adjacent socket and now it's on a third strip from an outlet on the other side of the room (can't go any further than that) none of these things eliminated the electrical noise coming from the phones. 

So at this point I need some advice on how to proceed with this problem, as is I can't really use the amp, so I can't really give any impressions just yet, it's disappointing but I know it has to have a solution, I can't be the only person connecting it to a PC chain, I read a great deal (this whole thread) and compared to its competitors (based on reviews) before getting this amp, it gives the tube performance and rollability I've really craved, so I'm keeping chin up that this can all be resolved. 

Pic of the Amp on a temp stand, having a proper wooden side table made but the lacquering isn't finished and it takes weeks to dry


----------



## Marutks

ArkNerevar said:


> I use my PC for everything



Have you tried some USB purifier?
I heard this is good  https://www.futureshop.co.uk/ifi-audio-nano-igalvanic3-0-audiophile-grade-galvanic-isolation


----------



## kimdeug (Dec 24, 2021)

ArkNerevar said:


> Hello everyone, after a considerable amount of research and contemplation/consideration of alternatives, I made the plunge from solid state to tube and now have a Cayin HA-6A! yay, I do however have a serious problem with my using it for which I'm now seeking some help.
> 
> When connected in my normal chain as Deezer HIFI/PC > silver plated USB > BRZHIFI DDC (digital to digital converter/clocker) > silver plated AES > XD05-Bal (BRZHIFI external linear power supply) functioning as DAC through aux port > silver plated 3.5-2RCA > HA-6A > ZMF stock OFC balanced cable > ZMF Verite open, I constantly have an electrical noise coming through the phones, sounds most like an old dial up modem, first thing I tried was to disconnect the AES cable and connect my phone to the DAC via USB, no electrical noise, with that I just hear the background hum that everyone here talks about, the one that is worst when on high impedance/UL mode, the to be expected HA-6A hum.
> 
> ...


Hi.
May be WI Fi or Bluetooth interference from computer. In my case I have to move 4 meters away from computer and Wi Fi router because of it. Try to connect directly to other sources excluding computer DAC. Like to TV via RCA  or CD player if possible. Or try to connect laptop to the DAC, but switch off WI FI, and play music saved on laptop (without WiFi and Power Supply -use laptop battery). This will give you an idea where the noise comes from. Is it USB ground noise or radio frequency Interference as Wi Fi or Anything else (in my case the LED strip regulator block behind the desk was causing this problem).

Merry Christmas to everyone!!!

Regards,
Kim


----------



## dvmrp

ArkNerevar said:


> Hello everyone, after a considerable amount of research and contemplation/consideration of alternatives, I made the plunge from solid state to tube and now have a Cayin HA-6A! yay, I do however have a serious problem with my using it for which I'm now seeking some help.
> 
> When connected in my normal chain as Deezer HIFI/PC > silver plated USB > BRZHIFI DDC (digital to digital converter/clocker) > silver plated AES > XD05-Bal (BRZHIFI external linear power supply) functioning as DAC through aux port > silver plated 3.5-2RCA > HA-6A > ZMF stock OFC balanced cable > ZMF Verite open, I constantly have an electrical noise coming through the phones, sounds most like an old dial up modem, first thing I tried was to disconnect the AES cable and connect my phone to the DAC via USB, no electrical noise, with that I just hear the background hum that everyone here talks about, the one that is worst when on high impedance/UL mode, the to be expected HA-6A hum.
> 
> ...


Just a very quick thought, have you tried different USB ports?


----------



## Andykong (Dec 24, 2021)

ArkNerevar said:


> Hello everyone, after a considerable amount of research and contemplation/consideration of alternatives, I made the plunge from solid state to tube and now have a Cayin HA-6A! yay, I do however have a serious problem with my using it for which I'm now seeking some help.
> 
> When connected in my normal chain as Deezer HIFI/PC > silver plated USB > BRZHIFI DDC (digital to digital converter/clocker) > silver plated AES > XD05-Bal (BRZHIFI external linear power supply) functioning as DAC through aux port > silver plated 3.5-2RCA > HA-6A > ZMF stock OFC balanced cable > ZMF Verite open, I constantly have an electrical noise coming through the phones, sounds most like an old dial up modem, first thing I tried was to disconnect the AES cable and connect my phone to the DAC via USB, no electrical noise, with that I just hear the background hum that everyone here talks about, the one that is worst when on high impedance/UL mode, the to be expected HA-6A hum.
> 
> ...



I try to illustrate your setup graphically as this is easier to debug a system logically with a block diagram and bullet points. Hope I get this right.





If red line will get rid of the electrical noise, that means the noise is coming from the signal path BEFORE the DAC, changing DAC, amp power cord or power or even the power connection is unlikely to change the electrical noise situation, logically.
Have you tried to connect the PC to DAC via a USB A to C OTG cable? Try to replicate the red connection?
Don't know anything about the DDC, is it powered by a switching power supply?  Is there a battery option with the DDC?  Switching power supply and adjustable dimmer are frequently the source of electrical noise in a tube amplifier system
When you want to debug a system, try to add one piece at a time to the system, start with PC to HA-6A directly with 3.5mm to RCA cable, then add DAC, then add DDC.  Don't bother with the sound quality at this stage, just focus on noise and hum.


----------



## rulerofrecords

Marutks said:


> Have you tried some USB purifier?
> I heard this is good  https://www.futureshop.co.uk/ifi-audio-nano-igalvanic3-0-audiophile-grade-galvanic-isolation


IF I'm not mistaken there is a DDC in the chain - so that should in all likelihood take care of that problem. Must be something else???? Happy Xmas btw everybody!!!!


----------



## ArkNerevar

Marutks said:


> Have you tried some USB purifier?
> I heard this is good


Interesting, I'm reading up on that, some good reviews but it's generally people saying it improved the background to some degree, no one exactly saying if it helped with a case like this but it's something to keep in mind thanks 



kimdeug said:


> May be WI Fi or Bluetooth interference from computer


my computer is connected by a hard line to a router 2 floors down #nooneshouldgameoverwifi



dvmrp said:


> Just a very quick thought, have you tried different USB ports?


yes including on the extra ports on the front of the case, still the noise



rulerofrecords said:


> IF I'm not mistaken there is a DDC in the chain - so that should in all likelihood take care of that problem.


there is yes...but it's an extremely cheap DDC, I wouldn't exactly say it's doing this "galvanic isolation" thing the unit he linked is 



Andykong said:


> Have you tried to connect the PC to DAC via a USB A to C OTG cable? Try to replicate the red connection?


yes on the XD05 and the schiit modi, no change



Andykong said:


> Don't know anything about the DDC, is it powered by a switching power supply? Is there a battery option with the DDC? Switching power supply and adjustable dimmer are frequently the source of electrical noise in a tube amplifier system


no it has a linear power supply from a transformer inside the chassis and I've tried with it disconnected from the chain entirely and with the XD05 running on battery & its external power supply disconnected, no change 



Andykong said:


> When you want to debug a system, try to add one piece at a time to the system, start with PC to HA-6A directly with 3.5mm to RCA cable, then add DAC, then add DDC. Don't bother with the sound quality at this stage, just focus on noise and hum.


The amp just plugged into the headphone jack on the motherboard? I didn't consider such a thing under the basis it might not be safe but if you say it is I can try but my cable for that isn't long enough, I've ordered another one but I won't get it for a few days



Andykong said:


> If red line will get rid of the electrical noise, that means the noise is coming from the signal path BEFORE the DAC, changing DAC, amp power cord or power or even the power connection is unlikely to change the electrical noise situation, logically


It seems so, it looks like the problem occurs when the PC is the source (which I need it to be) working on that theory I tried something, when I'm idling in windows the noise is a fluctuating electrical noise like a printer, when I open a game, the noise becomes a consistent noise like an old modem. I ran Cinebench which is a CPU benchmark, with it running so the CPU is at max the noise is unchanged, still the printer, then I manually set the GPUs fan to 100%, still the printer noise, then I ran the heaven benchmark for GPUs, noise becomes the old modem. 
So, it seems Its directly linked to my graphics card and how much load its under/how hard it's working.
Can I also say, wow you actually made a block diagram of my current audio chain? (and its right) thats kinda incredible, ive never had a company support that did that before, bravo man, much appreciated.


----------



## kimdeug (Dec 25, 2021)

ArkNerevar said:


> Interesting, I'm reading up on that, some good reviews but it's generally people saying it improved the background to some degree, no one exactly saying if it helped with a case like this but it's something to keep in mind thanks
> 
> 
> my computer is connected by a hard line to a router 2 floors down #nooneshouldgameoverwifi
> ...


The source of this  problem can be split in few categories, and the solution will depends from which category it is.

1.... Dirty signal ( Ground loop, USB ground loop, bad cables, dirty power supply)
2... Electromagnetic interference ( Wi Fi, frizzier, any electrical equipment with variable resistors and moving parts (LED light dimmer, coil whine from GPU, custom watercooling pump D5 or DDC))
3.... Noise tubes.
4.... Faulty part inside Cayin HA-6A
5.... One user noticed solving the problem after replacing internal fuse.

for each situation the diagnostic will be differ.

1... Power filter, use laptop with battery as a source without wifi (just for test) or connect to other sources as TV, CD, DVD etc, check the cables. Do you have more noise when scrolling any web page? or moving mouse?
2.... Avoid all interference.  I made a paper box test (described early)
3.... Roll the tubes 12AU7 a very cheap
4..... Can not help with this (my unit was replaced but waiting time was 6 months)
5.... Fuse are very cheap


----------



## kimdeug

ArkNerevar said:


> Interesting, I'm reading up on that, some good reviews but it's generally people saying it improved the background to some degree, no one exactly saying if it helped with a case like this but it's something to keep in mind thanks
> 
> 
> my computer is connected by a hard line to a router 2 floors down #nooneshouldgameoverwifi
> ...


You have mentioned that the noise related to your GPU. Question is: Is it dirty signal via USB cable from PC? Or Electromagnetic interference affecting the tubes?


----------



## ThanatosVI

My brother gifted me some Shuguang Black Treasure KT88 tubes for christmas. 

Really nice sounding tubes, could even be my favorites So far.

I'm pretty tired, so no qualified descriptions for now, but I certainly like them a lot!


----------



## dvmrp

ArkNerevar said:


> Interesting, I'm reading up on that, some good reviews but it's generally people saying it improved the background to some degree, no one exactly saying if it helped with a case like this but it's something to keep in mind thanks
> 
> 
> my computer is connected by a hard line to a router 2 floors down #nooneshouldgameoverwifi
> ...


Is every component connected to the same power bar?


----------



## ArkNerevar

dvmrp said:


> Is every component connected to the same power bar?


It was, ive tried with the amp on a second power bar and now on a third power bar from the other side of the room, also tried disconnecting the non vital things (DDC/external power supply) from the mains, no change


----------



## ungauged (Jan 11, 2022)

Got a really good deal on a HA-6A which I could not resist. While it does have some slight hiss/hum from the VO, it's dead quiet on the HEKse.

Been giving my trusty HA-2SE and the HA-6A a good detailed A/B.


----------



## Andykong

ArkNerevar said:


> Spoiler
> 
> 
> 
> ...



Let's try something dramatic.  If your motherboard has a built-in CPU that can provide basic function (I know, it's not good enough for gaming), remove your graphic card and stick with the default display driver, open up Youtube and check if the noise is reduced.  If we can prove that the noise is originated from the graphic card, then there is nothing much we can do with the current setup.  You have to look into specialised USB cleaner or isolator to minimise the noise generated by the graphic card.


----------



## ungauged

Can I check with you guys as it's not really clearly stated in the manuals. How would I know which toggle direction selects the appropriate option for the tube selection?

The part with the bump is the selected tube? Or the flat portion? So in this picture, I assume the selected tube is EL34?

Appreciate any advise. Cheers


----------



## ThanatosVI

ungauged said:


> Can I check with you guys as it's not really clearly stated in the manuals. How would I know which toggle direction selects the appropriate option for the tube selection?
> 
> The part with the bump is the selected tube? Or the flat portion? So in this picture, I assume the selected tube is EL34?
> 
> Appreciate any advise. Cheers


You're correct, switch Position is on EL34


----------



## ArkNerevar

Andykong said:


> Let's try something dramatic. If your motherboard has a built-in CPU that can provide basic function (I know, it's not good enough for gaming), remove your graphic card and stick with the default display driver, open up Youtube and check if the noise is reduced. If we can prove that the noise is originated from the graphic card, then there is nothing much we can do with the current setup. You have to look into specialised USB cleaner or isolator to minimise the noise generated by the graphic card.


I have a update on my noise problem, after some testing I could observe how the noise went up or down based on the GPUs load so the GPU was what was contaminating the usb signal, I accelerated my plans and got my new DAC that I had been planning on the Schiit Yggdrasil OG, the noise is now severly reduced to the point I can now listen to music while idling in windows and I now plan on getting the JCAT USB XE card to provide a fully clean signal, this should (hopefully) eliminate this electrical noise problem ive been having with what I can already tell is a awesome amp.

I also plan on making my first attempt to tube roll by replacing the voltage tubes with NOS sylvania 12AU7 black plates and replacing the KT88s with the supplied EL34s when I get the USB card, the idea being to burn them all in together.


----------



## ungauged (Jan 14, 2022)

To anyone having any issues with hum/hiss. If you have narrowed the problem down to your PC, I highly recommend the *iFi Audio iDefender+*.

I took a gamble to get rid of the interference from my PC and purchased it. Extremely doubtful at first but wow was I surprised that it has completely eliminated all the hum/hiss interference from my PC. As I stated earlier, the hum/hiss was only prevalent on the more sensitive ZMF VO. It's now totally gone and quiet passages on music are just beautiful.

I can safely say the Defender+ isn't snake oil.


----------



## ungauged (Jan 14, 2022)

ArkNerevar said:


> I have a update on my noise problem, after some testing I could observe how the noise went up or down based on the GPUs load so the GPU was what was contaminating the usb signal, I accelerated my plans and got my new DAC that I had been planning on the Schiit Yggdrasil OG, the noise is now severly reduced to the point I can now listen to music while idling in windows and I now plan on getting the JCAT USB XE card to provide a fully clean signal, this should (hopefully) eliminate this electrical noise problem ive been having with what I can already tell is a awesome amp.
> 
> I also plan on making my first attempt to tube roll by replacing the voltage tubes with NOS sylvania 12AU7 black plates and replacing the KT88s with the supplied EL34s when I get the USB card, the idea being to burn them all in together.


Strongly suggest you try the iFi Audio iDefender+ first. If it works, you'd be saving alot of $$$.


----------



## tinariwen

Thought I’d share a couple of impressions that have really changed my opinion of this amp for the better, and practically completely fixed the hum / hiss issue.



Like many of you, I use the HA-6A with high impedance cans, in my case the ZMF VCs and Aeolus. And, like many of you, this combination leads to an audible noise floor that can range from kinda quiet to very distracting. For me it was affected most by different 12AU7 tubes, but there was no rhyme or reason - I have some that are dead quiet, some that are ridiculously loud, and more than one pair of certain types that fall into both camps.



I’d got to the point where I was trying other amps to see if I could get the same sound but without the problems. One of my favourites was the Feliks Euforia AE, but not for the sound signature. It was way too neutral, but it did have an enormous soundstage - it filled every corner of the headphones, if that makes sense. It was also super quiet, but the sound didn’t have that particular tube magic, so it was sent back.



Then I happened across a comment over in the ZMF VC thread, where another user recommended the HA-6A for them, but only with an adapter. Curious, I messaged to find out what adapter they meant, and was put in touch with Skedra. Turns out Skedra also owns the HA-6A along with the ZMF VCs, and he also found the noise floor bothersome. Fortunately he also makes high-end cables over at Viking Audio, and decided to make himself an impedance adapter to fix the hiss problem.



After a bit of back and forth I ordered one, and it arrived super quick. It’s a short balanced adapter with a choice of litz cables, with the magic sauce being resistors built into the XLR connectors.



The difference it's made to my amp is night and day. The background is black, I’ve got way more play with volume, and I can now tube roll again without hiss being a deciding factor. I can hear all the different characteristics of my tubes, and can listen to scores with a wide dynamic range again. It’s almost like getting a brand new amp, and it’s put a stop to me hunting for a new one.



The second impression is of some KT-88 tubes, specifically the PSvane Mk-II versions. These are a touch more neutral than the ones that come as stock, but they have much better extension at both ends. Better still, the soundstage increases in width, but particularly in height. Using these almost rivals the soundstage I was getting from the Feliks Euforia, and now I get the black background thanks to the adapter, too.  As for the 12AU7s (for those interested), I've found that I prefer either RCA Clear Tops for a really wide and detailed sound without fatigue, or the Mullard CV4003 for a similar sound but with more focus on the mids and slightly less top end extension.  Both options still sound thick and lush in the mids, but with loads of detail thanks to the Psvane Kt88s.



If you’re interested in ordering one of the impedance adapters just drop Skedra a message. The guy is super helpful, very knowledgeable, and his work is spot on.


----------



## kimdeug

tinariwen said:


> Thought I’d share a couple of impressions that have really changed my opinion of this amp for the better, and practically completely fixed the hum / hiss issue.
> 
> 
> 
> ...


Will be very good if you upload the photo with adapter please.


----------



## tinariwen

kimdeug said:


> Will be very good if you upload the photo with adapter please.


I’m at work at the moment but will be able to over the next couple days.

It’s very unassuming though. It’s 20cm in length, black paracord cable and a male and female xlr connector at either end. Whilst it looks well made, it’s not obvious what it is.


----------



## kimdeug (Jan 15, 2022)

tinariwen said:


> I’m at work at the moment but will be able to over the next couple days.
> 
> It’s very unassuming though. It’s 20cm in length, black paracord cable and a male and female xlr connector at either end. Whilst it looks well made, it’s not obvious what it is.


Is that the similar item what we had discussed at the end of the page 17 and 18 on this forum?
 Relaxarus has got XLR one,  but did not like the sound alteration.
 I have used Ifi 3.5mm one, but my new replaced unit does not have this hiss problem anymore, so do not need it.


----------



## tinariwen

I’m not sure if the method used is the same. It’d be best to message Skedra as he’s likely to explain it better than I am.

As far as I can tell, there’s no degradation of sound. In fact, due to the blacker background I can hear more now, and there’s similar levels of detail to solid state. Also, I’m not noticing any change in sound signature. If there is one, it’s not something I can pick up on from the simple tests I’ve done, so that works for me.


----------



## kimdeug

tinariwen said:


> I’m not sure if the method used is the same. It’d be best to message Skedra as he’s likely to explain it better than I am.
> 
> As far as I can tell, there’s no degradation of sound. In fact, due to the blacker background I can hear more now, and there’s similar levels of detail to solid state. Also, I’m not noticing any change in sound signature. If there is one, it’s not something I can pick up on from the simple tests I’ve done, so that works for me.


Thanks. Link to Skedra, please, and how much if not a secret?


----------



## ThanatosVI (Jan 15, 2022)

kimdeug said:


> Thanks. Link to Skedra, please, and how much if not a secret?


It's nearly too easy. It's the Name of a head-fi User.
@skedra   , @kimdeug  wants to know about your impedance Adapter if I understood that correctly.

Kim you can also just click on his Name in my Post and "Start s private message"


----------



## kimdeug

ThanatosVI said:


> It's nearly too easy. It's the Name of a head-fi User.
> @skedra   , @kimdeug  wants to know about your impedance Adapter if I understood that correctly.
> 
> Kim you can also just click on his Name in my Post and "Start s private message"


Thanks ThanatosVI. 
Just have a little free time, and was thinking to make one by myself as have a lot of resistors and cables around.
Not critically needed, just in case of some noisy tubes during the rolling


----------



## rulerofrecords

Does anybody know if the KT170 works in the HA-6a without causing a major meltdown. Forgive me if that has been discussed before ...


----------



## ThanatosVI

rulerofrecords said:


> Does anybody know if the KT170 works in the HA-6a without causing a major meltdown. Forgive me if that has been discussed before ...


No KT120, KT150 and KT170 need too much current. 
Only KT88 are supported (and EL34 depending on switch position)


----------



## 19844

kimdeug said:


> Congrats. If you like sweet sound try the Sylvania 12AU7 NOS, They are very cheap around 10$ each green print. British made tubes Mullard, Brimar and CV.4003... not sure as do not remember the number are also sweet and soft. Do not be fullished by gold pins, like reissued JJ or ElectroHarmonics or Genalex or chinees Psvan gold pins tubes. They are looking nice, but is it all about the sound? I am listening with Tesla ECC802S now, and they are so close to 10 times expensive Telefunken E82CC. Regards, Kim
> 
> PS, for EL34 rolling try Reissued Russian Genalex KT77 tubes.



I would like to buy Tesla ECC802S but Im not sure which one should I buy(white or yellow logo) are they the same sound? 

Where did you buy it from? Thank you.


----------



## rulerofrecords

ThanatosVI said:


> No KT120, KT150 and KT170 need too much current.
> Only KT88 are supported (and EL34 depending on switch position)


Yup, understood. For some reason I thought the KT170 needed less ...


----------



## ThanatosVI

rulerofrecords said:


> Yup, understood. For some reason I thought the KT170 needed less ...


KT77 needs less (elwctrically identical to EL34 6AC7)

Maybe that was the type you had in mind?


----------



## rulerofrecords

ThanatosVI said:


> KT77 needs less (elwctrically identical to EL34 6AC7)
> 
> Maybe that was the type you had in mind?


No, I really did refer to the KT170 big bois


----------



## kimdeug

19844 said:


> I would like to buy Tesla ECC802S but Im not sure which one should I buy(white or yellow logo) are they the same sound?
> 
> Where did you buy it from? Thank you.


They are the same. Yellow are old production batch. I have a white one, but if I had a chance I will take a yellow lable.


----------



## Andykong

rulerofrecords said:


> Does anybody know if the KT170 works in the HA-6a without causing a major meltdown. Forgive me if that has been discussed before ...



Sorry for the late response, I can confirm that HA-6A cannot cope with KT120 and  KT170.


----------



## Andykong

All members in Cayin will start our Chinese New Year holiday today. During the holiday, all orders, inquires and after sales service will be processed immediately when we resume office on 10th February. 2022.

Thanks for all the support and we wish everyone to stay safe, healthy, and to have a wonderful Year of Tiger.





PS. Unlike previous years, I'll will take a break during the Chinese New Year vacation. I'll only check on forum occasionally. Please pardon me if I didn't resposne to your exchanges or PM promptly.


----------



## WillieB (Feb 10, 2022)

I have the HA-6A on order and it should be shipping in the next couple of days(after shut down for CNY is over). Can anyone offer any tips for initial setup? Also, I will be powering it with a 220V step-up transformer. I ordered a 220V model because the 110V is currently out of production and I failed to find one in the US. Anyone using theirs in a similar situation? Thanks for any insight!


----------



## joseG86

New member of the HA-6A family here. I was lucky to get a used unit of this beast amp from my new friend @Nikols with stock tubes (I plan on trying different ones)

After all I have read I expect 0 hum with my D8000 Pro, I will connect using RCA and SE, if this is really a step up from my Kinki THR-1 and the Feliks Elise I used to own I will be so very happy.......

José


----------



## tinariwen

joseG86 said:


> New member of the HA-6A family here. I was lucky to get a used unit of this beast amp from my new friend @Nikols with stock tubes (I plan on trying different ones)
> 
> After all I have read I expect 0 hum with my D8000 Pro, I will connect using RCA and SE, if this is really a step up from my Kinki THR-1 and the Feliks Elise I used to own I will be so very happy.......
> 
> José


I'd be interested to hear how you think it compares to the Feliks Elise.  I had the Euforia SE for a short while to compare to the HA-6A and found it to be to very neutral, almost SS like, although it had a huge soundstage.


----------



## joseG86

tinariwen said:


> I'd be interested to hear how you think it compares to the Feliks Elise.  I had the Euforia SE for a short while to compare to the HA-6A and found it to be to very neutral, almost SS like, although it had a huge soundstage.


The Feliks Elise with stock tubes was similar to Kinki THR-1 but then with RCA 6080 and CV181 MKII it was next level in detail, clarity, resolution and accuracy of the soundstage but to be honest I enjoyed the Kinki THR-1 more

Will give a short review as soon as I get the Cayin, probably next Tuesday/Wednesday


----------



## rulerofrecords

joseG86 said:


> The Feliks Elise with stock tubes was similar to Kinki THR-1 but then with RCA 6080 and CV181 MKII it was next level in detail, clarity, resolution and accuracy of the soundstage but to be honest I enjoyed the Kinki THR-1 more
> 
> Will give a short review as soon as I get the Cayin, probably next Tuesday/Wednesday


Hi there,
1. Congratulations! You'll like it - even if 0 hum is rare 
2. Did your THR-1 run free of issues??


----------



## joseG86

rulerofrecords said:


> Hi there,
> 1. Congratulations! You'll like it - even if 0 hum is rare
> 2. Did your THR-1 run free of issues??


Hello,

1. I cannot wait!
2. I bought it used here, one of the first units produced by Kinki, the relay came broken (left channel), I replaced it with a new one and fixed, 0 problem since then. The circuitry is very simple and accesible


----------



## rulerofrecords

joseG86 said:


> Hello,
> 
> 1. I cannot wait!
> 2. I bought it used here, one of the first units produced by Kinki, the relay came broken (left channel), I replaced it with a new one and fixed, 0 problem since then. The circuitry is very simple and accesible


Roger that! Wednesday is only roughly 120 hours away ...


----------



## WillieB

Well, my order for a 220V unit fell through. The seller put me on hold until after the holiday(so two weeks wasted). They refunded my money yesterday and indicated that I will need to wait until May or June to get one. I think the guy is just confused and forgot that I was willing to accept a 220V. I know that no one has 110V models right now, but anyone know of a used one for sale anywhere of either voltage? I am pursuing vendors on Ali Express at this point. I found several that claim to have the 220V unit so I ordered one, for a higher price of course, and now the vendor is telling me it will be "factory shipped" and delivered on the 21st of this month. I'll bet 50k that this will NEVER happen, but I'm trying to be optimistic. I'm hoping to get some news today. Either way, I have definitely decided that this is the amp that I want. It's ridiculous that I have spent a month trying to buy one. You can't sell a product that you don't have. It's a shame that they can't seem to manage their inventory any better. Well, sorry for the rant, but I'm hoping to find one soon. Any suggestions welcome and thanks!


----------



## joseG86 (Feb 12, 2022)

WillieB said:


> Well, my order for a 220V unit fell through. The seller put me on hold until after the holiday(so two weeks wasted). They refunded my money yesterday and indicated that I will need to wait until May or June to get one. I think the guy is just confused and forgot that I was willing to accept a 220V. I know that no one has 110V models right now, but anyone know of a used one for sale anywhere of either voltage? I am pursuing vendors on Ali Express at this point. I found several that claim to have the 220V unit so I ordered one, for a higher price of course, and now the vendor is telling me it will be "factory shipped" and delivered on the 21st of this month. I'll bet 50k that this will NEVER happen, but I'm trying to be optimistic. I'm hoping to get some news today. Either way, I have definitely decided that this is the amp that I want. It's ridiculous that I have spent a month trying to buy one. You can't sell a product that you don't have. It's a shame that they can't seem to manage their inventory any better. Well, sorry for the rant, but I'm hoping to find one soon. Any suggestions welcome and thanks!


Hi there Willie,

There's a unit available @ eBay from German seller https://www.ebay.com/itm/325044842752?hash=item4bae2eb100:g:rw0AAOSwNUBhVwMM try and send an offer ;D

One more: https://www.hifi-amplifiers.com/en/...class-a-headphone-power-amplifier-p-5534.html


----------



## Nikols

joseG86 said:


> The Feliks Elise with stock tubes was similar to Kinki THR-1 but then with RCA 6080 and CV181 MKII it was next level in detail, clarity, resolution and accuracy of the soundstage but to be honest I enjoyed the Kinki THR-1 more
> 
> Will give a short review as soon as I get the Cayin, probably next Tuesday/Wednesday


Looking forward to your review!

I have to say i really enjoy this amp, the hum for me is a real conundrum. Ive used it with hd800s and susvaras with very different results. There was an audible noise floor with the hd800s, for me its like these headphones act like a stethoscope, i could hear the hum but also tubes heating up between songs. With music playing this wasnt an issue and i still enjoyed the ha-6a with these headphones.

The susvaras were another storey entirely. The soundfloor is absolutely black, completely silent,  even on high gain. I really am enjoying this combination 95% of the time. The amp is pushed hard by the susvaras and sometimes it hits its limit.


----------



## joseG86

Nikols said:


> Looking forward to your review!
> 
> I have to say i really enjoy this amp, the hum for me is a real conundrum. Ive used it with hd800s and susvaras with very different results. There was an audible noise floor with the hd800s, for me its like these headphones act like a stethoscope, i could hear the hum but also tubes heating up between songs. With music playing this wasnt an issue and i still enjoyed the ha-6a with these headphones.
> 
> The susvaras were another storey entirely. The soundfloor is absolutely black, completely silent,  even on high gain. I really am enjoying this combination 95% of the time. The amp is pushed hard by the susvaras and sometimes it hits its limit.


The Susvaras will never cease to amaze me, it looks like a conspiracy theory when someone gets those cans to its full potential haha

I will probably enjoy it 100%, I enjoyed the Elise and this is probably way better with 2 sound signatures in 1 and of course, tube rolling game!

Thanks mate!


----------



## Newsee

WillieB said:


> Well, my order for a 220V unit fell through. The seller put me on hold until after the holiday(so two weeks wasted). They refunded my money yesterday and indicated that I will need to wait until May or June to get one. I think the guy is just confused and forgot that I was willing to accept a 220V. I know that no one has 110V models right now, but anyone know of a used one for sale anywhere of either voltage? I am pursuing vendors on Ali Express at this point. I found several that claim to have the 220V unit so I ordered one, for a higher price of course, and now the vendor is telling me it will be "factory shipped" and delivered on the 21st of this month. I'll bet 50k that this will NEVER happen, but I'm trying to be optimistic. I'm hoping to get some news today. Either way, I have definitely decided that this is the amp that I want. It's ridiculous that I have spent a month trying to buy one. You can't sell a product that you don't have. It's a shame that they can't seem to manage their inventory any better. Well, sorry for the rant, but I'm hoping to find one soon. Any suggestions welcome and thanks!


I was eying this amp for quite long time, but the reported hum problems kept me on hold. I have ended up with McIntosh MHA200, and really happy with it. Depending on your HP you might give it a try.


----------



## ThanatosVI

WillieB said:


> Well, my order for a 220V unit fell through. The seller put me on hold until after the holiday(so two weeks wasted). They refunded my money yesterday and indicated that I will need to wait until May or June to get one. I think the guy is just confused and forgot that I was willing to accept a 220V. I know that no one has 110V models right now, but anyone know of a used one for sale anywhere of either voltage? I am pursuing vendors on Ali Express at this point. I found several that claim to have the 220V unit so I ordered one, for a higher price of course, and now the vendor is telling me it will be "factory shipped" and delivered on the 21st of this month. I'll bet 50k that this will NEVER happen, but I'm trying to be optimistic. I'm hoping to get some news today. Either way, I have definitely decided that this is the amp that I want. It's ridiculous that I have spent a month trying to buy one. You can't sell a product that you don't have. It's a shame that they can't seem to manage their inventory any better. Well, sorry for the rant, but I'm hoping to find one soon. Any suggestions welcome and thanks!


This reminds me of how I ended up with the Cayin Ha-6a. 
At First I wanted a Primaluna Evo 300 but just like for you now, that one wasn't available for months. 
That's why I chose the Cayin instead...


----------



## Nikols

joseG86 said:


> The Susvaras will never cease to amaze me, it looks like a conspiracy theory when someone gets those cans to its full potential haha
> 
> I will probably enjoy it 100%, I enjoyed the Elise and this is probably way better with 2 sound signatures in 1 and of course, tube rolling game!
> 
> Thanks mate!


I love the UL mode on this amp. It really accentuates vocals and strings. The ability to flick between this and triode on the fly is pretty cool.


----------



## krude (Feb 14, 2022)

Apologies if this question appeared here before, does anyone know the power figures for the HA6a?
This site seems to suggest around 4.5W using KT88 (per channel?) ... into an unspecified Ohms. The site also gives two power figures L and H : https://www.audioemotion.co.uk/cayin-ha-6a-tube-headphone-amplifier---type-uk-23306-p.asp

I tried running 1266 TC and Susvara, and it can barely get it to decent volume while totally maxing out the VU meters (they are stiff at 100%).

I was wondering, if there is a H and L gain switch and maybe I'm at low gain? Because it does behave like it is giving out around 1-2w into 60 Ohm? There is no gain switch I'm aware of on the amp tho


----------



## Andykong (Mar 31, 2022)

krude said:


> Apologies if this question appeared here before, does anyone know the power figures for the HA6a?
> This site seems to suggest around 4.5W using KT88 (per channel?) ... into an unspecified Ohms. The site also gives two power figures L and H : https://www.audioemotion.co.uk/cayin-ha-6a-tube-headphone-amplifier---type-uk-23306-p.asp
> 
> I tried running 1266 TC and Susvara, and it can barely get it to decent volume while totally maxing out the VU meters (they are stiff at 100%).
> ...



Those are different settings of Impedance Matched Output of HA-6A.  Theoretically vacuum tube amplifier does not have a gain control, you cannot mainpulate the gain ratio to achieve higher output power with tube amplifier.  The impedance mateching output are different "outlet" from the output transformer, they are specially developed to accomodate different impedance loading of headphones.  There are three settings:  L for Low impedance 8Ω~64Ω; M for Mid impedance 65Ω~250Ω;  H for High impedance 251Ω~600Ω.

The ouptut  of HA-6A is kind of complicated, it is affect by three settings: impedance, Triode/ultralinear and KT88/EL34, the complete specification is as follow:







With AB1266 and Susavar,  you can try both low impedance and Mid impedance setting.  KT88 with ultralinear mode will offer the highest output.   By the way, don't compare the rated output of transformer coupled tube amplfier with solid state amplfier directly.  A decent output transformer will provide ample current reserve and that makes a lot of different when you are dealing with difficult loads.


----------



## krude (Feb 14, 2022)

Andykong said:


> Those are different settings of Impedance Matched Output of HA-6A.  Theoretically vacuum tube amplifier does not have a gain control, you can mainpulate the gain ratio to achieve higher output power with tube amplifier.  The impedance mateching output are different "outlet" from the output transformer, they are specially developed to accomodate different impedance loading of headphones.  There are three settings:  L for Low impedance 8Ω~64Ω; M for Mid impedance 65Ω~250Ω;  H for High impedance 251Ω~600Ω.
> 
> The ouptut  of HA-6A is kind of complicated, it is affect by three settings: impedance, Triode/ultralinear and KT88/EL34, the complete specification is as follow:
> 
> ...


Great explanation, thank you. I use Holo May L2 balanced (that's 5.3V output or there abouts) into HA6a. When using Susvara for example, I get VU meters maxed out at around 11 o'clock and at that point I can already hear dynamics compression, when I get to 12 o'clock I get more distortion, so at that point the amp is under more than 100% load already. Is that what I should expect?


----------



## Andykong

krude said:


> Great explanation, thank you. I use Holo May L2 balanced (that's 5.3V output or there abouts) into HA6a. When using Susvara for example, I get VU meters maxed out at around 11 o'clock and at that point I can already heard dynamics compression, when I get to 12 o'clock I get more distortion, so at that point the amp is under more than 100% load already. Is that what I should expect?



Are you using Triode of Ultralinear setting? with KT88 or EL34?  at Low impedance setting?  With XLR4 or 6.35mm phone connection?

When I don't know your HA-6A setting, I couldn't provide any meaningful comment.


----------



## krude

Andykong said:


> Are you using Triode of Ultralinear setting? with KT88 or EL34?  at Low impedance setting?  With XLR4 or 6.35mm phone connection?
> 
> When I don't know your HA-6A setting, I couldn't provide any meaningful comment.


Sure, sorry, this is KT88, Ultralinear, balanced in, 4 pin balanced out, medium impedance.


----------



## krude

Andykong said:


> Are you using Triode of Ultralinear setting? with KT88 or EL34?  at Low impedance setting?  With XLR4 or 6.35mm phone connection?
> 
> When I don't know your HA-6A setting, I couldn't provide any meaningful comment.


Actually, based on your previous answer, I just tried lowering the output from the DAC (Holo May is quite hot on balanced) to see if a lower input level would affect the distortion to power output, and I think it does. If I drop the output from the DAC to around 2/3rds it seems I can get more volume without running into compression and distortion territory so early. Would that make sense?


----------



## ArkNerevar

@Andykong We can see the announcement for HA-300 MKII (now black) can you provide us with any info for such a thing for the HA-6A? maybe a MKII with more volume steps, less gain and fixed on the hissing problem, any sort of indication would probably put the minds of a number of people at ease.


----------



## Andykong

krude said:


> Actually, based on your previous answer, I just tried lowering the output from the DAC (Holo May is quite hot on balanced) to see if a lower input level would affect the distortion to power output, and I think it does. If I drop the output from the DAC to around 2/3rds it seems I can get more volume without running into compression and distortion territory so early. Would that make sense?



Yes, if the output of your DAC is adjustable, please stick with 4V output for balanced connection.  The 5.3V input to HA-6A is fine most of the time, but when you drive it high and pushing the amplifier to its limit, the higher input level will become the source of distortion.


----------



## Andykong (Feb 14, 2022)

ArkNerevar said:


> @Andykong We can see the announcement for HA-300 MKII (now black) can you provide us with any info for such a thing for the HA-6A? maybe a MKII with more volume steps, less gain and fixed on the hissing problem, any sort of indication would probably put the minds of a number of people at ease.



We don't have any plan to revise HA6A.  It's not listed even on R&D schedule, so I can comfortably said you won't see a MK2 of HA-6A in next 12 or even 18 months.


----------



## WillieB

Newsee said:


> I was eying this amp for quite long time, but the reported hum problems kept me on hold. I have ended up with McIntosh MHA200, and really happy with it. Depending on your HP you might give it a try.


The MHA200 is a great option. I really wish


ArkNerevar said:


> @Andykong We can see the announcement for HA-300 MKII (now black) can you provide us with any info for such a thing for the HA-6A? maybe a MKII with more volume steps, less gain and fixed on the hissing problem, any sort of indication would probably put the minds of a number of people at ease.


I have considered the MHA200, but I have an amp already that uses miniature tubes. Also, it's power output is limited for my application. I have not totally eliminated it, though, because other said amp can always be a pre-amp to my more powerful SS amps to drive my less efficient planars. I was really hoping for something with larger tubes/output values so that I can use some of those headphones purely on tubes.

Wait, Hissing? I thought the noise problems were already sorted on the HA-6A? Also, due to the difficulty finding an HA-6A, I am considering just opting for the HA-300. How much of an upgrade is that amp(if at all)? I really thought it to be less flexible/tunable due to it being 300b/SET.


----------



## krude

Andykong said:


> Yes, if the output of your DAC is adjustable, please stick with 4V output for balanced connection.  The 5.3V input to HA-6A is fine most of the time, but when you drive it high and pushing the amplifier to its limit, the higher input level will become the source of distortion.


Awesome, following the thought process I switched to rca and indeed it works a lot better especially for heavy loads. Thank you  now I can rock my TC and Susvara from it 🤘


----------



## Andykong

krude said:


> Awesome, following the thought process I switched to rca and indeed it works a lot better especially for heavy loads. Thank you  now I can rock my TC and Susvara from it 🤘



What is the output level of your DAC with RCA? 4V in RCA might be a bit too hot too.


----------



## krude

Andykong said:


> What is the output level of your DAC with RCA? 4V in RCA might be a bit too hot too.


Just checked and it's actually 5.8V balanced and 2.9V RCA, so that should be good 👍


----------



## ArkNerevar

Andykong said:


> We don't have any plan to revise HA6A.  It's not listed even on R&D schedule, so I can comfortably said you won't see a MK2 of HA-6A in next 12 or even 18 months.


Great thanks for the detailed response, it should help people faced with a "is the new thing around the corner" thought trap (a pretty serious affliction I might add)



WillieB said:


> The MHA200 is a great option. I really wish
> 
> I have considered the MHA200, but I have an amp already that uses miniature tubes. Also, it's power output is limited for my application. I have not totally eliminated it, though, because other said amp can always be a pre-amp to my more powerful SS amps to drive my less efficient planars. I was really hoping for something with larger tubes/output values so that I can use some of those headphones purely on tubes.


I looked at the MHA200 before getting the HA-6A, now I wasn't able to listen to the MHA200 but a friend whose ears I mostly trust did listen to one for me in america (and the HA-6A ofc) he basically said that the MHA200 was good yeah but on a pure sound fidelity level it wasn't even in the same league as the HA-6A, he pretty much confirmed other first-hand comments from people, that a big part of the MHA200 is its size, specifically its footprint, it's very small (he said in person its even smaller than the photos, that it looked cute) so it's very desk friendly, the HA-6A is not exactly desk friendly, for some people this is a big deal so keep that in mind.

Thats just on the sound fidelity, it has other factors, like the small power tubes you mentioned so its power output is extremely low, no way you'll run actually demanding headphones on it and an extremely strange and possibly unique volume control, my friend found it incredibly annoying to use, to me it sounded like it's been designed that way to be used with a line out volume box /shrug, but hey you might really like the McIntosh sound and want to place your tube amp on a desk so then it's much more appealing. 



WillieB said:


> Wait, Hissing? I thought the noise problems were already sorted on the HA-6A? Also, due to the difficulty finding an HA-6A, I am considering just opting for the HA-300. How much of an upgrade is that amp(if at all)? I really thought it to be less flexible/tunable due to it being 300b/SET.


I feel I have to clarify on that, what people described from the first production units sounded pretty dire, what I hear now not even close to what they said, is it silent? no, still some background hiss on my verité's (which are well known to pick it up) it does change on what output settings you have and what voltage tubes you have in, on some tubes it is virtually silent, but I have a separate problem to do with this, my hiss is unbalanced, one channel is worse than the other that's consistent over different tubes, but I do believe that my amp is damaged, besides this I also have a channel imbalance that can be seen on the VU meters, so I don't think this is normal, just my unit has a problem, I'm going to contact my dealer to see what we can do about it, might have to return it if we can't come to a solution.

In regards to the HA-300, also looked at that one before getting the HA-6A, people I spoke to said yeah the sound fidelity is higher but you are mostly stuck with the type of sound it gives out, no adjustable output mode (triode/ultralinear, very cool feature) and no power tube rolling, now the 300B is an extremely famous tube for a good reason, it sounds awesome, everyone agrees it sounds awesome, my dad's 2 channel system is SET with REAL western electric 300B, so I know that it's awesome but I also know what it sounds like and I don't want to have that sound for my personal headphone chain or at least I don't want to have ONLY that sound for my personal headphone chain, the HA-6A is extremely rollable, when I showed my dad the little chart with useable power tubes he was actually impressed that I could try all of these tubes (or valves as he says) and when I explained the adjustable output mode he did say that's a pretty nifty feature to have, so you see the HA-6A does have its points that you can't just say the HA-300 is the superior unit, it's going to come down to what you're looking for, hope this helps.


----------



## joseG86

I just received the HA-6A and it's heating up already.

This is by far one of the best money spent in my life, will give sound impressions later compared to the latest amps I had and I pretty much remember their sound.... SA-1, Jotunheim 2, Feliks Elise and the one I still have and love like a son, the Kinki THR-1

Thanks again @Nikols


----------



## joseG86 (Feb 18, 2022)

I want to begin my "review" by saying that this is the best amp I have ever had, both visually and technically speaking. It is beautiful.

I decided to get the HA-6A because I saw the review of @Relaxasaurus (Midfi Guy on YT) and he's one of a very selective few that I trust on YT

_My unit is already 1 year old, so the valves already have x hours of use_

The very first time I plugged it in, there was a very noticeable hiss, the cursed hiss I've read a lot here about the HA-6A so instead of crying like a baby I removed all the tubes, plug them back again, but not KT88. I used the EL34, moved the switch behind the amp to EL34 position and voila: 0 hum, 0 hiss, 0 noise, very very black background, you can
hear there's something but it is very black. After checking out about the fact that the hiss was gone, I plugged KT88 back again and no noise at all either. ("Fixed" by restarting I guess)

*Sound impressions with KT88, default valves, I preferred TR to UL with these:*
_(D8000 Pro, no EQ, volume at 9:00 position most of the time. RCA+SE, low impedance position)_

Big sound, big body, never boring, every single instrument has its own personality, its own place and its own position within the soundstage... Layering and depth is impressive when the music allows it. Very holographic.

Every single instrument has texture, you can feel it, it is virtually solid in front of you, you can't see it but it is there, has its own importance and relevance...

Bass is amazing, going very low and with this valves sometimes a bit boomy but very sweet, the midrange is there, vocals are really good, a bit forward to me but never too intimate and the treble is on pair, very detailed and never strident

Resolution compared to let's say the Kinki is like going from 1080 to 4K, the naturality and organic sound of instruments makes you smile like a child, like how is this possible? this is just headphones!!

The quality of what you're hearing is so detailed that you can even know how big the concert hall is because the reproduction of the air between the instruments, the echoes, resonance etc.... It is like you are really there, very very hard to really get this feeling on headphones. Never felt any brightness.


*Sound impressions with EL34, default valves, I preferred UL to TR with these:*
_(D8000 Pro, no EQ, volume at 9:00 position most of the time. RCA+SE, low impedance position)_

Sound is not as big or full as with the KT88 valves but this time we're going for surgical accuracy and precision of the sound, while still being a romantic and funny mix of tubey sound and SS, never sterile or boring

Again, every single instrument has its own texture but with even more resolution than KT88, I could say EL34 for classical music might be the best if you want to experience the ultimate detailed experience

The soundstage gave me the impression of being a little bit smaller than KT88 but with more coherence and maybe, realistic. I know my music and I spent many hours everyday listening to it so I'm not afraid to say that

Bass is amazingly detailed and linear, never boomy and never too much, even if I give 8dB+ to 20-60hz it will still sound very precisse and never loose

Midrange is to die for, I had never listened to voices with this resolution, detail and realism, specially women, you can even draw their faces, it's like they are in front of you singing for you haha

Strings are simply amazing, it is so very very very detailed and accurate than a simple guitar can transform your listening experience

Piano, for the first time sounds like piano, from the very first keystroke you know that is a real piano, I've heard many live and I know how they're supposed to sound, you can get that experience with this amp and EL34

Treble is never strident either with this valves, very detailed and sweet. Never felt any brightness.

*Cons:*
- (Not Cayin's fault) I will probably have to change the EH 12au7, one of them is probably dying and I get an interference in the right channel (after many hours of use), which is where the valve is and I tested it by hitting it with a pencil and
you can hear is not a solid hit, like something vibrates inside more than it should. Luckily they are very cheap so I might try different brand, I wonder if buying valves with low power needed will reduce any hiss even more

- 100 watts of use, compared to the 10-20 watts of the Kinki, still I don't really mind, I get pleasure for 100 watts and the room gets heated, not really a 'con' haha
The amp made me have to buy a new table to place it on, we're talking 20-25 kg of weight it is no joke, but it looks so very beautiful....

*Final notes:*

I never expected to have this kind of amp, I've always wanted to get the best sound by spending the less possible, I was close to it with THR-1 or Elise but somehow decided to try this and while it's not end game for me because I know I will end my journey with SS, this is worth it for real, this is not a joke of an amp.

You can really play with it using all the tubes you want, adapters, TR, UL, different impedances,
any headphone you throw at it will work, SE, 4.4 or XLR..... And whatever you do, the quality of the sound is going to be superb

Again, this is my first Cayin, I don't care where they come from or where they are, I'm just honored to have a piece of gear designed by beings that made me enjoy my music even more and provided joy in the darkest of times

José
_(Thank you to @ThanatosVI for his inestimable help)_


----------



## ThanatosVI

joseG86 said:


> I want to begin my "review" by saying that this is the best amp I have ever had, both visually and technically speaking. It is beautiful.
> 
> I decided to get the HA-6A because I saw the review of @Relaxasaurus (Midfi Guy on YT) and he's one of a very selective few that I trust on YT
> 
> ...


Glad I could help you enjoy this nice amp 
Together with the D8000 Pro and the Pontus II you have quite the Setup.


----------



## WillieB

ArkNerevar said:


> Great thanks for the detailed response, it should help people faced with a "is the new thing around the corner" thought trap (a pretty serious affliction I might add)
> 
> 
> I looked at the MHA200 before getting the HA-6A, now I wasn't able to listen to the MHA200 but a friend whose ears I mostly trust did listen to one for me in america (and the HA-6A ofc) he basically said that the MHA200 was good yeah but on a pure sound fidelity level it wasn't even in the same league as the HA-6A, he pretty much confirmed other first-hand comments from people, that a big part of the MHA200 is its size, specifically its footprint, it's very small (he said in person its even smaller than the photos, that it looked cute) so it's very desk friendly, the HA-6A is not exactly desk friendly, for some people this is a big deal so keep that in mind.
> ...


Thanks for the great replies. It really sounds like the HA-6A is everything I hoped it to be, but after a month of trying to get one, I gave up. I've had my order cancelled twice because there was no stock and these are out of production. I ordered a third time from an Ali Express vendor who showed them in stock(220v model that I was going to run with a SU transformer), but later found out he had nothing. He was selling factory direct. After a few days of beating around the bush, I decided to cancel that order. Of course, he argued with me for about a day before accepting the cancellation. I will NEVER make that mistake again. It turns out he could have forced the amp on me if he wanted and could manage to get it to ship within 10 days(before Ali cancels for non-shipment). In the end, I just can't justify doing any more business with a company that can't manage it's own inventory any better than this. What happens if I need a part or the amp needs repair? They don't even have repair facilities in the US that I can find. How long would I be stuck with a 45lb paper weight? This entire experience has just reminded me of almost every reason why I should be avoiding Chinese products any time that it's in any way possible. From the shoddy customer service to the crooked vendors that make deals that they can't deliver on, I'm done with the whole lot of them.

Now, ranting aside, I opted for the Ampsandsound Mogwai SE Rev 2 instead. Not as fancy, but it will take the nice tubes that I already bought for the Cayin, and it gets a lot of good reviews and recommendations for use with Verite, which is my favorite headphone. Who knows, maybe the HA-6A will be available in the US again one day and maybe I will decide that I can't live without it after all. If so, great. For the time being, I'm just glad to have something on the way that should fit nicely into my plans for my system. Thanks again!


----------



## nichino

joseG86 said:


> I want to begin my "review" by saying that this is the best amp I have ever had, both visually and technically speaking. It is beautiful.
> 
> I decided to get the HA-6A because I saw the review of @Relaxasaurus (Midfi Guy on YT) and he's one of a very selective few that I trust on YT
> 
> ...


Great review, José!

I'm actually close to making a decision on the HA-6A but wasn't sure about its synergies with the Pontus II - is this what you pair with the HA-6A?

Cheers,
Nick


----------



## joseG86

nichino said:


> Great review, José!
> 
> I'm actually close to making a decision on the HA-6A but wasn't sure about its synergies with the Pontus II - is this what you pair with the HA-6A?
> 
> ...


Hi there,

Thank you mate, yes I pair it with the Pontus II using Mogami's RCA, it is really good and detail retrieval much better than with Feliks Elise and upgraded valves


----------



## tinariwen

joseG86 said:


> I want to begin my "review" by saying that this is the best amp I have ever had, both visually and technically speaking. It is beautiful.
> 
> I decided to get the HA-6A because I saw the review of @Relaxasaurus (Midfi Guy on YT) and he's one of a very selective few that I trust on YT
> 
> ...


Hey José, how would you say it compares with the Jot2? I know they’re in completely different ball parks price-wise, and obviously different tech. I’ve been looking for a good bang-for-buck SS amp, and as I use the Bifrost 2 it can sit neatly in a stack without taking up more desk space.

I’ve been trying to decide between the Jot2, or selling the Bifrost2 and getting a Chord Hugo TT (1st version). I’m just not sure how much I’ll use an SS amp as I love the HA-6A sound, but I’d like something that is comparable


----------



## joseG86

tinariwen said:


> Hey José, how would you say it compares with the Jot2? I know they’re in completely different ball parks price-wise, and obviously different tech. I’ve been looking for a good bang-for-buck SS amp, and as I use the Bifrost 2 it can sit neatly in a stack without taking up more desk space.
> 
> I’ve been trying to decide between the Jot2, or selling the Bifrost2 and getting a Chord Hugo TT (1st version). I’m just not sure how much I’ll use an SS amp as I love the HA-6A sound, but I’d like something that is comparable


Hi there!

I had both Jot 2 and Bifrost 2, while I could have lived with Bifrost 2 as DAC the Jot 2 is kind of bright on the treble, depending on the headphone you use, it can be amazing or make it too bright.

It has 2 sound signatures one for SE and one for XLR, XLR is more energetic with more punch, also preamp for both XLR and RCA and tons of power, on a different league compared to HA-6A that's for sure but it is very cheap for all the features

I never tried Hugo TT but I've read it doesn't have the best amp


----------



## joseG86 (Feb 24, 2022)

Edit: Hiss/hum is gone, it is very very low with D8000 Pro using socket savers, it is still here but this time very low hiss, with EL34 almost inaudible. EH 12au7 valves have very thin pins

Edit: I connected my very first tube amp, a Loxjie P20 and the D8000 Pro has very slight hiss and hum, like 60% hiss and 40% hum, it is hard to hear but it is there and I am a freak of silence.... F hell. And in all power outlets in my house, both grounded and not grounded. Even with only the UPS connected without power line......


José


----------



## nichino

joseG86 said:


> Hi there,
> 
> Thank you mate, yes I pair it with the Pontus II using Mogami's RCA, it is really good and detail retrieval much better than with Feliks Elise and upgraded valves


Appreciate the reassurance, @joseG86 👍- I've gone ahead and ordered a set after auditioning.

Coincidentally I also own the Jot2 and I agree with your comparison of the 2 😀


----------



## Deleeh

joseG86 said:


> Edit: Right socket of ECC82/12au7 is loose, the valve inside moves very easy to any direction, if I remove the right 3.5mm plug from my headphones the hum disappears so it is the right socket 100%, If switch the valves it does the same so it is a socket problem. I won't try to tightening it or do any tricks yet  and wait for the socket saver with thick pins to arrive.... If you have a different solution for this loose socket let me know
> 
> Edit 2: I rotated a little bit the valve inside the socket and the hum is now gone, I hope the socket saver has thick pins so I can get mental peace, at this point there's no longer hum but it is the right socket, I'll ask @Andykong if he could ask any Cayin engineer on how to proceed, tighten or replace the socket by experienced technician in Spain
> 
> ...


Hello,
Great report, thanks.

How do you feel about the Feliks compared to the Cayin?
Does it beat the Feliks or both on the same eye level?


----------



## joseG86 (Feb 20, 2022)

Deleeh said:


> Hello,
> Great report, thanks.
> 
> How do you feel about the Feliks compared to the Cayin?
> Does it beat the Feliks or both on the same eye level?


They're very different, you could have both and you'd maybe reach end game haha

HA-6A: Speed, micro and macrodynamics, resolution, detail retrieval, layering and depth, very honest soundstage, big when it's big and small when it's small....

F. Elise MKII w stock tubes was warm, slow and very relaxing sounding (which is really good), with Psvane CV181 MKII and RCA6080 becomes faster and resolution improves but the Cayin plays in a different league IMHO

José


----------



## joseG86

2nd day with 0 issues, no hiss no hum,nothing, just perfect organic, natural, detailed and amazing sound with stock EL34 valves (my favorites so far)

Will give more impressions when I get new 12au7 and Psvane MK2 KT88


----------



## joseG86

joseG86 said:


> 2nd day with 0 issues, no hiss no hum,nothing, just perfect organic, natural, detailed and amazing sound with stock EL34 valves (my favorites so far)
> 
> Will give more impressions when I get new 12au7 and Psvane MK2 KT88


I got my Psvane KT88 MK2 and the soundstage is bigger and more detailed compared to GL KT88, unfortunately as happened before with all the tube amps I had, the D8000 Pro will develop hiss/hum and never be a black background

I've put for sale my unit with all the tubes I already bought, I don't really want to change my headphones as I really love the D8000 Pro but this amp is god like for real.

Thanks!!


----------



## lumdicks

joseG86 said:


> I got my Psvane KT88 MK2 and the soundstage is bigger and more detailed compared to GL KT88, unfortunately as happened before with all the tube amps I had, the D8000 Pro will develop hiss/hum and never be a black background
> 
> I've put for sale my unit with all the tubes I already bought, I don't really want to change my headphones as I really love the D8000 Pro but this amp is god like for real.
> 
> Thanks!!


The hum may be caused by Ground Loop and you may try iFi Ground Defender on your HA-6A. I am having low frequency hum in my Fostex HP-V8 with D8000, and just got the iFi Ground Defender today and it is magic! The amp is now dead silent with all my headphones including D8000 and the ultra sensitive Focal Stellia.


----------



## joseG86

lumdicks said:


> The hum may be caused by Ground Loop and you may try iFi Ground Defender on your HA-6A. I am having low frequency hum in my Fostex HP-V8 with D8000, and just got the iFi Ground Defender today and it is magic! The amp is now dead silent with all my headphones including D8000 and the ultra sensitive Focal Stellia.


I tried everything, I am back to Kinki THR-1 and the blackest background haha


----------



## tinariwen

joseG86 said:


> I tried everything, I am back to Kinki THR-1 and the blackest background haha


How does the kinki compare with the ha-6a? I’ve read some reviews and it seems to have some tube amp traits with all the usual solid state benefits. Is that your experience?


----------



## joseG86

tinariwen said:


> How does the kinki compare with the ha-6a? I’ve read some reviews and it seems to have some tube amp traits with all the usual solid state benefits. Is that your experience?


Hi there,

Compared to Kinki, the HA-6A destroys the Kinki in every sound aspect, specially with Psvane MK2 KT88 valves, with the Kinki it's like your seat is far away from the orchestra while with the HA-6A feels like front row seats haha, you really get the sense to be there, specially if the recording is really good (triode mode)


----------



## itslikeboo

joseG86 said:


> Hi there,
> 
> Compared to Kinki, the HA-6A destroys the Kinki in every sound aspect, specially with Psvane MK2 KT88 valves, with the Kinki it's like your seat is far away from the orchestra while with the HA-6A feels like front row seats haha, you really get the sense to be there, specially if the recording is really good (triode mode)


I guess that’s not a huge surprise. Though the difference in power output between the Kinki and HA-6A must be pretty substantial.


----------



## Loftprojection (Mar 11, 2022)

@Andykong with this big announcement of new amps, any chance we might see a new version of the HA-6A using a regular volume control or at least a stepped attenuator with way more steps than 24?  I feel it is a shame to have designed such a great, flexible amp and use a 24 step attenuator!  It may be very good sound wise but for people like me who like to micro adjust the level it is really bad.

Anyone here bought an HA-6A and subsequently installed another volume pot?


----------



## tinariwen

Hey all,

Has anyone tried this amp with the Susvara?  I've come across a pair for a decent price, but I really don't want to fall into the rabbit hole of trying out different speaker amps just for one set of cans.  On paper the amp is powerful enough, but everyone who owns the Susvara talks about speaker amps and trying to get the most out of them.


----------



## krude

tinariwen said:


> Hey all,
> 
> Has anyone tried this amp with the Susvara?  I've come across a pair for a decent price, but I really don't want to fall into the rabbit hole of trying out different speaker amps just for one set of cans.  On paper the amp is powerful enough, but everyone who owns the Susvara talks about speaker amps and trying to get the most out of them.


If you're not ready for a rabbit hole don't buy Susvara 🤠


----------



## joseG86

Loftprojection said:


> @Andykong with this big announcement of new amps, any chance we might see a new version of the HA-6A using a regular volume control or at least a stepped attenuator with way more steps than 24?  I feel it is a shame to have designed such a great, flexible amp and use a 24 step attenuator!  It may be very good sound wise but for people like me who like to micro adjust the level it is really bad.
> 
> Anyone here bought an HA-6A and subsequently installed another volume pot?


If I had the knowledge I'd change the pot instantly for a 48 steps, with D8000 Pro I rarely go past 9 o'clock using SE+RCA


----------



## Nikols

tinariwen said:


> Hey all,
> 
> Has anyone tried this amp with the Susvara?  I've come across a pair for a decent price, but I really don't want to fall into the rabbit hole of trying out different speaker amps just for one set of cans.  On paper the amp is powerful enough, but everyone who owns the Susvara talks about speaker amps and trying to get the most out of them.


I ran susvaras off the ha-6a for a few weeks. The first thing i noticed was the VU's jump to the maximum and pretty much stayed there, constantly topping out. In terms of peformance the amp handled 90% of what the susvaras demanded of it but i think it was pushed to its limits and underperformed loosing detail on busier passages of music. I couldnt shake the feeling that i was asking too much it and in the end i opted for an enleum amp 23r. This amp demonstrated for me what the ha-6a was missing with the susvaras... the bass has so much more extension and punch, timbre and detail retrieval is on another level.

One definate positive was i had zero hiss with the ha-6a with the susvaras, it really was a joy. The soundfloor was non existant compared to my hd800s.


----------



## Loftprojection

joseG86 said:


> If I had the knowledge I'd change the pot instantly for a 48 steps, with D8000 Pro I rarely go past 9 o'clock using SE+RCA


Yea, I've read a few reviews that complain about this 24 steps pot.  I really wonder why they chose that direction for such a great amp, if they are really totally nuts about stepped at Cayin, at least put one that let's users micro adjust at that price bracket.


----------



## krude

Nikols said:


> I ran susvaras off the ha-6a for a few weeks. The first thing i noticed was the VU's jump to the maximum and pretty much stayed there, constantly topping out. In terms of peformance the amp handled 90% of what the susvaras demanded of it but i think it was pushed to its limits and underperformed loosing detail on busier passages of music. I couldnt shake the feeling that i was asking too much it and in the end i opted for an enleum amp 23r. This amp demonstrated for me what the ha-6a was missing with the susvaras... the bass has so much more extension and punch, timbre and detail retrieval is on another level.
> 
> One definate positive was i had zero hiss with the ha-6a with the susvaras, it really was a joy. The soundfloor was non existant compared to my hd800s.


I run HA6a with Susvara and TC for a few months now, yes you definitely push it near the limit but I think you can stay on the right side of the limit and still get amazing performance, especially for the money. Add to that that you can roll both KT88 and EL34 type tubes, and preamp tubes, 3 impedance levels, balanced and SE outputs and the triode / ultralinear modes and you've got a sound palette that is pretty much unrivalled. It will be a tube amp in the end, so not last word in detail etc. but that's what good solid state amps are for. As purely a tube amp I think you can get very good value from HA6a for all cans including Susvara and TC.


----------



## Nikols (Mar 19, 2022)

krude said:


> I run HA6a with Susvara and TC for a few months now, yes you definitely push it near the limit but I think you can stay on the right side of the limit and still get amazing performance, especially for the money. Add to that that you can roll both KT88 and EL34 type tubes, and preamp tubes, 3 impedance levels, balanced and SE outputs and the triode / ultralinear modes and you've got a sound palette that is pretty much unrivalled. It will be a tube amp in the end, so not last word in detail etc. but that's what good solid state amps are for. As purely a tube amp I think you can get very good value from HA6a for all cans including Susvara and TC.


I agree with you about the performance.it wasnt lacking and i didnt find the susvaras subdued. I always found the ha-6a's real strength to be string instruments and female vocals. This only improved with the susvaras. The enleum has similar strengths, ive seen it descibed as having a tubey sound. It brought incredible bass extension and more refined detail retrieval especially with strings.

I bought the susvaras with the intension of running them off the ha-6a but moved it on as i felt uncomfortable that the amp did seem to be at its upper limit running them. Maybe i'm misguided, i just feel that if i'm pushing equipment constantly to that level it might shorten its lifespan... i was used to my hd800s asking very little effort of the ha-6a.


----------



## krude (Mar 19, 2022)

Nikols said:


> I agree with you about the performance.it wasnt lacking and i didnt find the susvaras subdued. I always found the ha-6a's real strength to be string instruments and female vocals. This only improved with the susvaras. The enleum has similar strengths, ive seen it descibed as having a tubey sound. It brought incredible bass extension and more refined detail retrieval especially with strings.
> 
> I bought the susvaras with the intension of running them off the ha-6a but moved it on as i felt uncomfortable that the amp did seem to be at its upper limit running them. Maybe i'm misguided, i just feel that if i'm pushing equipment constantly to that level it might shorten its lifespan... i was used to my hd800s azking very little effort of the ha-6a.


I found tubes and especially more complex designs like HA6a to be able to offer much more once you dig deeper. For example I was initially running it through balanced in, but learned that I can get much more headroom going through lower voltage single ended and using higher volume on the amp. Susvara gels very well for me with KT88 in both triode and ultralinear modes and TC with EL34.

On the subject of SS vs tube I went the other way pretty much. I mostly use the Soloist GT which plays to all SS strenghts and sounds nothing like tubes, and HA6a for the tube sound. Also HA6a needs to run for at least 15 minutes before the performance stabilises. It definitely requires experimentation but can yield shockingly good results if setup to use it's strengths.


----------



## itslikeboo

I’m interested in this amp as well to drive my Susvaras but it feels a bit silly to turn it down based on just one pair of headphones I own. I see Cayin also sells the CS-55a, a similar priced tube speaker amp with upped wpc and a headphone output. I wonder how it compares to the HA-6A.


----------



## Nikols (Mar 19, 2022)

krude said:


> I found tubes and especially more complex designs like HA6a to be able to offer much more once you dig deeper. For example I was initially running it through balanced in, but learned that I can get much more headroom going through lower voltage single ended and using higher volume on the amp. Susvara gels very well for me with KT88 in both triode and ultralinear modes and TC with EL34.
> 
> On the subject of SS vs tube I went the other way pretty much. I mostly use the Soloist GT which plays to all SS strenghts and sounds nothing like tubes, and HA6a for the tube sound. Also HA6a needs to run for at least 15 minutes before the performance stabilises. It definitely requires experimentation but can yield shockingly good results if setup to use it's strengths.


I ran mine from a single ended source too. Given the amp converts balanced input to single ended before creating a balanced output I didnt see the point in the extra step.

Definately agree it needs 20 mins warm up to settle, i'm in that habit now even with my new amp. The ha-6a is a phenominal amp, beautiful to look at and beautiful to listen too. My preference was kt88 in UL mode for my music tastes.


----------



## justanut

Hi everyone. I’ve been trying to decide between the Felike Euforia and the Cayin, and I think I’ve made up my mind!

Can I check what are the recommended tubes to get for my 800S? I don’t mind rolling a couple of tubes to find my preferred sound. But not blindly buying every single tube out there either 😅

Also, has anyone ventured to try the IE900 out of the HA-6A?


----------



## joseG86 (Mar 21, 2022)

So after I decided not to sell the amp and understand how it works such beast with such headphones as the D8000 Pro, I am really enjoying this HA-6A and stopped using the Kinki THR-1

I have tried different rectifier, preamp and power valves and I think the stock valves are amazing pairing for D8000 Pro, got new EH 12au7 and there's no hiss anymore, there's a very very low hum that I can only notice if I focus on it

The Psvane KT88 MK2 gives a really accurate and tight sound but they remind me of SS too much while GL KT88 with EH 12au7 gives that very slight tubey sound and a bit of warm that really enhances the missing bass from D8000 Pro making it extremely enjoyable where everything sounds incredibly amazing

I also tried RCA Radiotron 12au7 and they give a very big soundstage bringing the midrange back while having a very controlled bass and kind of bright treble

For 22de4 rectifier I tried Sicte Pavia but I can't find much difference with the RCA, I guess these valves have a job that won't make music sound different at all

I have 2 Ruby KT88 incoming to compare with the GL's but so far, I think stock valves with this amp are already an amazing set and you pretty much don't need to buy more valves, only replacements, unless you go for NOS



justanut said:


> Hi everyone. I’ve been trying to decide between the Felike Euforia and the Cayin, and I think I’ve made up my mind!
> 
> Can I check what are the recommended tubes to get for my 800S? I don’t mind rolling a couple of tubes to find my preferred sound. But not blindly buying every single tube out there either 😅
> 
> Also, has anyone ventured to try the IE900 out of the HA-6A?


I had the Elise and I would always choose the HA-6A

Edit: Question for tube amp experts, when I was trying to find what could make the hum I removed the 12au7 valves like Midfi Guy did and the hum was present without them, I guess it is just the output power with my sensitive HP, my connection is RCA+SE low impedance


----------



## justanut

I've placed my order for the HA-6A~ long waiting list though and expected to only receive it end-June~ Going to be a very slow couple of months!


----------



## tinariwen

justanut said:


> Hi everyone. I’ve been trying to decide between the Felike Euforia and the Cayin, and I think I’ve made up my mind!
> 
> Can I check what are the recommended tubes to get for my 800S? I don’t mind rolling a couple of tubes to find my preferred sound. But not blindly buying every single tube out there either 😅
> 
> Also, has anyone ventured to try the IE900 out of the HA-6A?


I had both at home for a while. The Euforia sounds a lot more like a solid state amp, but without harsh edges. The soundstage is much bigger in both width and height, and the background is definitely quieter. It’s probably more dynamic, too.

The Cayin is way more versatile, and can either sound thick and syrupy or clean like the Euforia, depending on tube rolling. I kept the Cayin because I like being able to switch sound profiles.


----------



## krude

tinariwen said:


> I had both at home for a while. The Euforia sounds a lot more like a solid state amp, but without harsh edges. The soundstage is much bigger in both width and height, and the background is definitely quieter. It’s probably more dynamic, too.
> 
> The Cayin is way more versatile, and can either sound thick and syrupy or clean like the Euforia, depending on tube rolling. I kept the Cayin because I like being able to switch sound profiles.


Indeed HA6a is a supremely tweakable amp, which also is the main reason I enjoy it


----------



## itslikeboo

Anyone heard the lead time on ordering one of these?


----------



## justanut

itslikeboo said:


> Anyone heard the lead time on ordering one of these?


I ordered last month and was told that stock will only arrive mid-June~


----------



## tinariwen

Anyone tried the new ZMF Atrium with the ha-6a?


----------



## Andykong

tinariwen said:


> Anyone tried the new ZMF Atrium with the ha-6a?


Someone tried this combination at CanJam Singapore, check it out *HERE*.


----------



## krude

Just a straight up appreciation post. I'm recently running EL34s with TC and Susvara a lot, and I don't know if it's my maturity, listening at lower levels and taking out some of the bass, or system burnin, or both, but the level of performance I'm getting is through the roof. Both TC and Susvara sound absolutely spectacular. Bass weight (no bloat), midrange clarity and detail and smooth detailed air with big images. Awesome, I'm falling in love with HA6a all over again.


----------



## krude

Completely separate post, anyone has any experience with Mullard 12au7? Also anyone tried 12at7 or 12ax7 of any description?


----------



## ArkNerevar

krude said:


> Also anyone tried 12at7 or 12ax7 of any description?


if your thinking of running those in the HA-6A, drop the idea, they require more plate current and have much higher gain than AU7, AT7 has 3 times AX7 has 5 times, gain aside the amp wont have the plate current to power them and the bias will be radically different.



krude said:


> anyone has any experience with Mullard 12au7?


given the very high price of these tubes today, no im rolling my way through a variety of other cheaper tubes before I put down that type of cash, its not exact as they will be different amps but you can check online what people say about them in general outside of the HA-6A.


----------



## Andykong

krude said:


> Just a straight up appreciation post. I'm recently running EL34s with TC and Susvara a lot, and I don't know if it's my maturity, listening at lower levels and taking out some of the bass, or system burnin, or both, but the level of performance I'm getting is through the roof. Both TC and Susvara sound absolutely spectacular. Bass weight (no bloat), midrange clarity and detail and smooth detailed air with big images. Awesome, I'm falling in love with HA6a all over again.



Interesting, I tried Susvara with EL34 on HA-6A and prefer the KT88 presentation, I didn't look at it from your perspective, especially on the low-level part.  I am a loud listener.  I must try the Susvara and EL34 In low-level again.  Thanks for the sharing.


----------



## krude

ArkNerevar said:


> if your thinking of running those in the HA-6A, drop the idea, they require more plate current and have much higher gain than AU7, AT7 has 3 times AX7 has 5 times, gain aside the amp wont have the plate current to power them and the bias will be radically different.
> 
> 
> given the very high price of these tubes today, no im rolling my way through a variety of other cheaper tubes before I put down that type of cash, its not exact as they will be different amps but you can check online what people say about them in general outside of the HA-6A.


You can still import a pair from US or UK for relatively affordable price, but they are going up and its harder to find nowadays. Which 12au7s would you recommend and why? Stocks are good, can't complain, but want to see whats possible in terms of SQ.


----------



## ArkNerevar

krude said:


> You can still import a pair from US or UK for relatively affordable price,


could you show me a example of this please, could be something I missed myself



krude said:


> Which 12au7s would you recommend and why?


sorry but I cant recommend anything just yet, im burning in a whole bunch of power & voltage tubes on the amp so its not being tested in a like for like comparision, where the other tubes are the same so I can hear the difference of just one tube change, in the future I will post about my impressions of all of these tubes.


----------



## krude

ArkNerevar said:


> could you show me a example of this please, could be something I missed myself
> 
> 
> sorry but I cant recommend anything just yet, im burning in a whole bunch of power & voltage tubes on the amp so its not being tested in a like for like comparision, where the other tubes are the same so I can hear the difference of just one tube change, in the future I will post about my impressions of all of these tubes.


There are some decent options on ebay at the moment. Hifishark 🤠 ill be doing some rolling myself in a few weeks after we move house.


----------



## tinariwen

krude said:


> Completely separate post, anyone has any experience with Mullard 12au7? Also anyone tried 12at7 or 12ax7 of any description?


I’ve got the Mullards. Smooth mids, rolled off but sweet treble. Bass not bloated, doesn’t extend all the way down. The soundstage also loses a lot of height, so it feels like two blobs either side of your head.

I remember reading somewhere that a company in the US got a tonne of them for a good price, and then created an artificial scarcity by driving the prices up and claiming that they’re gods gift in 12AU7s. Everyone bought the hype and the price increases followed suit.

They’re good, but not worth the price imo. The Sylvanias do a better job and retain more detail, more bass impact and better highs.


----------



## krude

tinariwen said:


> I’ve got the Mullards. Smooth mids, rolled off but sweet treble. Bass not bloated, doesn’t extend all the way down. The soundstage also loses a lot of height, so it feels like two blobs either side of your head.
> 
> I remember reading somewhere that a company in the US got a tonne of them for a good price, and then created an artificial scarcity by driving the prices up and claiming that they’re gods gift in 12AU7s. Everyone bought the hype and the price increases followed suit.
> 
> They’re good, but not worth the price imo. The Sylvanias do a better job and retain more detail, more bass impact and better highs.


Awesome, thank you for solid info 🙌🍻


----------



## tinariwen

Has anyone compared the HA-6A to any of the ampandsound amps? I’ve got a feeling that they probably follow the Feliks Euforia sound sig, which is to say more neutral with good extension, so akin to solid state.

The HA-6A for me is more of a chameleon with that tube rolling and various settings, but I do love the look of those ampandsound amps. Not easy to come by in the UK though


----------



## Newbman123

Just got a used cayin HA6a which I believe was bought late in 2021. I am loving it for most things but somehow I think it lacks that attack that I have heard in another amp(Auris euterpe with 6sn7 tubes replacing the 3cc83 stock, which my friend did say have compressed dynamics with the stock 3cc83). I was wondering if there is any other tube combination that will do this for me? Sadly I do not see the 6sn7 in the recommended tubes list. I am new to tube rolling so I am not really sure about these things. I saw quite a few posts listing that the sound was made warmer but I saw none that addressed bass attack and immediacy. My current setup is as follows : Phone ->Dethonray honey -> Cayin HA6a(KT 88 stock in high impedence mode tried in both UL and TR modes) -> HD650(SE). I am awaiting cables for my holo spring with a singxer su2 as a ddc, so cannot check with that setup yet  . Also have the atrium coming in, not sure if that will help.
Any help would be much appreciated


----------



## ThanatosVI (Jun 19, 2022)

@Andykong The Design of this new amp looks great. Resembles the 25th Anniversary amp aesthetically.
https://cayin.com/produkt/cayin-soul-170-kt-170-roehrenverstaerker/

Can we get a pure headphone amp with that Design?
Edit: Talking about aesthetics here. I find it visually pleasing.


----------



## iFi audio

ThanatosVI said:


> Can we get a pure headphone amp with that Design?



KT170s are a bit much for headphones, but some folks here on HF use their tough cans with speaker amps, so who knows right ?


----------



## ThanatosVI

iFi audio said:


> KT170s are a bit much for headphones, but some folks here on HF use their tough cans with speaker amps, so who knows right ?


I actually meant the aesthetic design not the tube choice.
Like how the 25th Anniversary amp and this new "Soul" look like.

Actually KT170 is an incredibly bad choice with the current russia Situation,  as there is only Tung Sol producing it (it's a new design from Tung Sol after all)


----------



## Newbman123 (Jun 20, 2022)

Umm, guys I made boo boo while removing the tubes and forgot to mark which pin goes where. Can someone send a spec for this? I am unable to find any online.

Edit: Just realized there is a notch there that protects me from my stupidity......


----------



## tinariwen

Newbman123 said:


> Just got a used cayin HA6a which I believe was bought late in 2021. I am loving it for most things but somehow I think it lacks that attack that I have heard in another amp(Auris euterpe with 6sn7 tubes replacing the 3cc83 stock, which my friend did say have compressed dynamics with the stock 3cc83). I was wondering if there is any other tube combination that will do this for me? Sadly I do not see the 6sn7 in the recommended tubes list. I am new to tube rolling so I am not really sure about these things. I saw quite a few posts listing that the sound was made warmer but I saw none that addressed bass attack and immediacy. My current setup is as follows : Phone ->Dethonray honey -> Cayin HA6a(KT 88 stock in high impedence mode tried in both UL and TR modes) -> HD650(SE). I am awaiting cables for my holo spring with a singxer su2 as a ddc, so cannot check with that setup yet  . Also have the atrium coming in, not sure if that will help.
> Any help would be much appreciated


I found the PSVane KT88 and RCA Clear Tops to be the most solid state like, with faster transients than the supplied setup.

Neither compare well to a more neutral, faster tube amp (in terms of speed, transients, detail etc). I haven’t heard the Auris, but the difference between the Cayin and the Feliks Euforia is pretty stark, with the Euforia being the faster amp. It pairs far better with the new ZMF Atrium, whereas I preferred the Verite Closed on Cayin as it softened the attack somewhat. I think the Atrium and Euforia hits a Goldilocks zone for me


----------



## iFi audio

Newbman123 said:


> Edit: Just realized there is a notch there that protects me from my stupidity......



Yep, it should be there and is very helpful 



ThanatosVI said:


> I actually meant the aesthetic design not the tube choice.
> Like how the 25th Anniversary amp and this new "Soul" look like.



Understood, thanks for that clarification


----------



## RobSF

Any view on the HA-6A driving the HEDDphone?


----------



## busseysound

I am now the proud owner of an HA-6A!  Listened to many, many amps at the recent Chicago CanJam and my favorite was the HA-6A (even over the 300).  Moving up from an MJ2, so I have lots of 12AU7 tubes to try as well.  So excited!  Got it from the friendly folks at ZMF.


----------



## Andykong

Newbman123 said:


> Just got a used cayin HA6a which I believe was bought late in 2021. I am loving it for most things but somehow I think it lacks that attack that I have heard in another amp(Auris euterpe with 6sn7 tubes replacing the 3cc83 stock, which my friend did say have compressed dynamics with the stock 3cc83). I was wondering if there is any other tube combination that will do this for me? Sadly I do not see the 6sn7 in the recommended tubes list. I am new to tube rolling so I am not really sure about these things. I saw quite a few posts listing that the sound was made warmer but I saw none that addressed bass attack and immediacy. My current setup is as follows : Phone ->Dethonray honey -> Cayin HA6a(KT 88 stock in high impedence mode tried in both UL and TR modes) -> HD650(SE). I am awaiting cables for my holo spring with a singxer su2 as a ddc, so cannot check with that setup yet  . Also have the atrium coming in, not sure if that will help.
> Any help would be much appreciated



The Dethonray honey is a DAC/Amp?  No fixed voltage line out?  What is the volume setting on Dethonray honey and HA-6A when you listen to HD650?  I suspect the high output of your source (DAC supposedly) has limited the dynamic of the HA-6A when you need to maintain the system at low-noise, non-clipping conditions. 

You only need a pair of RCA cables to connect the holo spring to HA-6A, you can skip the DDC initially.  RCA interconnect are widely available in hardware stores at a very low cost, maybe you can get one pair for the short term and check out the Spring + HA-6A before you do any tube rolling.  

By the way, if you want to test the attack of your system, HD650 is not the headphone I'll recommend.


----------



## Andykong

ThanatosVI said:


> @Andykong The Design of this new amp looks great. Resembles the 25th Anniversary amp aesthetically.
> https://cayin.com/produkt/cayin-soul-170-kt-170-roehrenverstaerker/
> 
> Can we get a pure headphone amp with that Design?
> Edit: Talking about aesthetics here. I find it visually pleasing.





ThanatosVI said:


> I actually meant the aesthetic design not the tube choice.
> Like how the 25th Anniversary amp and this new "Soul" look like.
> 
> Actually KT170 is an incredibly bad choice with the current russia Situation,  as there is only Tung Sol producing it (it's a new design from Tung Sol after all)



Unlikely we'll develop a headphone amp in this design because the HA-300, HA-6A, and HA-300MK2 have more or less set a brand face for Cayin tube headphone amplifier.  Our forthcoming tube headphone amplifier will adopt a similar design to maintain the brand value.  

There is no such thing as a bad choice because there isn't any choice to start with.  you either give up this product opportunity or you just do your best and hope for the best.  Fortunately, the 120/150/170 projects are well received and Cayin is well rewarded both financially and through brand advancement.


----------



## ThanatosVI

Andykong said:


> Unlikely we'll develop a headphone amp in this design because the HA-300, HA-6A, and HA-300MK2 have more or less set a brand face for Cayin tube headphone amplifier.  Our forthcoming tube headphone amplifier will adopt a similar design to maintain the brand value.
> 
> There is no such thing as a bad choice because there isn't any choice to start with.  you either give up this product opportunity or you just do your best and hope for the best.  Fortunately, the 120/150/170 projects are well received and Cayin is well rewarded both financially and through brand advancement.


Looking forward to the new addition to Cayins headphoneamp lineup. Any rough timeline on when we can expect details?
Personally I"d be a fan if Cayin adopted 2A3 tubes in addition to their 300B and KT88/EL34

It's understandable that Cayin went through with the Release of the amp, after all the development that went into it, but I would argue that starting a new design with KT170 now would be quite a bad choice. (I have a KT150 amp myself, it's not about the tube per se, but the logistic Situation around it)


----------



## Newbman123

Andykong said:


> The Dethonray honey is a DAC/Amp?  No fixed voltage line out?  What is the volume setting on Dethonray honey and HA-6A when you listen to HD650?  I suspect the high output of your source (DAC supposedly) has limited the dynamic of the HA-6A when you need to maintain the system at low-noise, non-clipping conditions.
> 
> You only need a pair of RCA cables to connect the holo spring to HA-6A, you can skip the DDC initially.  RCA interconnect are widely available in hardware stores at a very low cost, maybe you can get one pair for the short term and check out the Spring + HA-6A before you do any tube rolling.
> 
> By the way, if you want to test the attack of your system, HD650 is not the headphone I'll recommend.


Honey has a line out mode limited to 2v so that i do not think is the issue.
As for lack of attack on 650, perhaps 😅. I am eagerly awaiting my atrium. I'll update once i get that and set up the holo. I'm also having a usb c to usb b cable made with some extra shielding because i have a few other cables lying along that path😅.
I didn't mean to say the bass and attack was bad in anyway, just that it's more solid state like while i expected a bit more umph from tubes.
Full system should be up and running in a month or so. I'll take a call then. It might also be that the tubes are not burnt in. I believe the previous owner had put in less than 50-60hrs on it(he got a nirvana a month after he got the ha-6a i believe 😅). I think i just might go for a tung sol 6550 just in case because i heard that i has a lot more low end albeit at the expense of some treble sparkle sometime in the future, would you agree with the description i have given for the 6550 @Andykong ? Ooh and also does the ha6a support 6sn7 by any chance?
 Also appreciate the reply 😁


----------



## Andykong

ThanatosVI said:


> Looking forward to the new addition to Cayins headphoneamp lineup. Any rough timeline on when we can expect details?
> Personally I"d be a fan if Cayin adopted 2A3 tubes in addition to their 300B and KT88/EL34
> 
> It's understandable that Cayin went through with the Release of the amp, after all the development that went into it, but I would argue that starting a new design with KT170 now would be quite a bad choice. (I have a KT150 amp myself, it's not about the tube per se, but the logistic Situation around it)



You cannot consider a product as-is because the branding effect is more than the sales volume or margin of a product.  With the KT170 project, there are intangible benefits such as brand advancement, recognition, and attention we received internationally simply because we are among the first few brands to deliver a high-quality all-new design for KT170.  We literally expanded our sales network and drive the sales of our other integrated amplifiers because of that.


----------



## ThanatosVI

Andykong said:


> You cannot consider a product as-is because the branding effect is more than the sales volume or margin of a product.  With the KT170 project, there are intangible benefits such as brand advancement, recognition, and attention we received internationally simply because we are among the first few brands to deliver a high-quality all-new design for KT170.  We literally expanded our sales network and drive the sales of our other integrated amplifiers because of that.


As a fan of the brand I am glad that it still had a positive effect.

It does look stunning


----------



## Andykong

Newbman123 said:


> Honey has a line out mode limited to 2v so that i do not think is the issue.
> As for lack of attack on 650, perhaps 😅. I am eagerly awaiting my atrium. I'll update once i get that and set up the holo. I'm also having a usb c to usb b cable made with some extra shielding because i have a few other cables lying along that path😅.
> I didn't mean to say the bass and attack was bad in anyway, just that it's more solid state like while i expected a bit more umph from tubes.
> Full system should be up and running in a month or so. I'll take a call then. It might also be that the tubes are not burnt in. I believe the previous owner had put in less than 50-60hrs on it(he got a nirvana a month after he got the ha-6a i believe 😅). I think i just might go for a tung sol 6550 just in case because i heard that i has a lot more low end albeit at the expense of some treble sparkle sometime in the future, would you agree with the description i have given for the 6550 @Andykong ? Ooh and also does the ha6a support 6sn7 by any chance?
> Also appreciate the reply 😁



you seem to have a lot of variables/uncertainties in your system and they will be finalized/clarified in the next few weeks, I'd suggest you don't do anything dramatic until you have completed your setup as planned. 

Sorry, you can't use 6SN7 with HA-6A, please refer to the recommended replacement list in your HA-6A user guide.


----------



## busseysound

Just ordered the Genelex Gold Lion KT88's to replace the Electro-Harmonix EL34's that came with the amp.  From the research I've done this should be a good decision.  I'm sure others here have done the same?


----------



## busseysound

Also forgot to mention in the post above...  I did quite a bit of 12AU7/ECC82 tube rolling with the new amp from tubes I still had with my MJ2:

RFT ECC82
Tungsram black plate ECC82
Baldwin  12AU7
RCA 5814A
Sylvania 12AU7 long black plate, square getter from 1953

The Sylvania is still my favorite with the RFT a close second.


----------



## ThanatosVI

busseysound said:


> Just ordered the Genelex Gold Lion KT88's to replace the Electro-Harmonix EL34's that came with the amp.  From the research I've done this should be a good decision.  I'm sure others here have done the same?


Yours did not come with both?


----------



## busseysound

ThanatosVI said:


> Yours did not come with both?


I thought it was supposed to, but I ended up buying the demo unit I listened to at the Chicago CanJam from ZMF.  They said it didn't come with them, but gave me a discount.


----------



## Andykong

*HA-3A*, a little brother of HA-6A and HA-300MK2.  More information and photo next week.


----------



## krude (Jul 1, 2022)

Hi guys,

I need help.

I've been rolling tubes, tried Electroharmonix el34, Electroharmonix 12au7, Gold Lion ecc82, Gold Lion KT88 and Black Treasure EL34.

Gold Lion Ecc82 were the new tubes I was testing. When I put them in the right channel was dead. I swapped them and both channels were working. Amp sounded great.

After about an hour I turned the system off, came back 2h later, turned it on left channel was dead again. I swapped the Ecc82s again and this time both channels were dead ...

Then I swapped to my old trusty Electroharmonix 12au7, no luck, swapped the power tubes. Tried all combinations ...

No luck, both channels are dead.

Inspected the whole chain, everything else works with no issues.

Help?


----------



## tinariwen

krude said:


> Hi guys,
> 
> I need help.
> 
> ...


I had a very similar problem and the fuse had somehow blown inside. There should be spares in the box with the manual, and you get to the fuse by removing the base plate.


----------



## krude

tinariwen said:


> I had a very similar problem and the fuse had somehow blown inside. There should be spares in the box with the manual, and you get to the fuse by removing the base plate.


You are correct kind sir, the inside fuse was blown. Got the Gold Lion ECC82 singing again. Need to do some burn in but very impressed with the initial sessions. 

Also ... I need to get more of those fuses lol


----------



## shafat777

Can 12at7 tubes be used with this amp? I have a plethora of at7 from my Cap modded MJ2 and have been thinking about selling that to get a Ha6a. I have nothing but footscrays 4033s and would hate to have to waste those if the HA6a dont work with 12at7. 

Thank you


----------



## busseysound

Was able to try my first KT88 tubes - some Tesla Vsrvoice I found on eBay.  REALLY loved the sound - transparent.  Unfortunately one of the two tubes would "pop" in my headphone and then be dead.  Re-seating sometimes worked, sometimes didn't.

So after quite a bit of research I'm going to try the KR KT88 - I've read very good things.  Anyone ever tried them in this amp?


----------



## ThanatosVI

busseysound said:


> Was able to try my first KT88 tubes - some Tesla Vsrvoice I found on eBay.  REALLY loved the sound - transparent.  Unfortunately one of the two tubes would "pop" in my headphone and then be dead.  Re-seating sometimes worked, sometimes didn't.
> 
> So after quite a bit of research I'm going to try the KR KT88 - I've read very good things.  Anyone ever tried them in this amp?


Never tried them myself, but from what I read they are super transparent and detailed, well extended and neutral.

So not very warm and "tubey" but rather solid state like with some tube qualities on top


----------



## krude (Jul 4, 2022)

busseysound said:


> Was able to try my first KT88 tubes - some Tesla Vsrvoice I found on eBay.  REALLY loved the sound - transparent.  Unfortunately one of the two tubes would "pop" in my headphone and then be dead.  Re-seating sometimes worked, sometimes didn't.
> 
> So after quite a bit of research I'm going to try the KR KT88 - I've read very good things.  Anyone ever tried them in this amp?


KT88 is considered by many the better choice. From my experience the difference is between particular tubes / makes / even examples rather than type. I'm currently on Gold Lion ECC82 and Gold Lion KT88.

Very good detail, quite sharp, very good bass extension, not as smooth as other tubes can be (like Black Treasure and Electroharmonix EL34). Depends on the headphone that combo may be too much for some brighter and sharper sets.

I'll be testing Electroharmonix KT88 and Gold Lion KT77 (aka EL34) soon and hopefully some vintage Sylvania 12AU7 soon as well.


----------



## krude

shafat777 said:


> Can 12at7 tubes be used with this amp? I have a plethora of at7 from my Cap modded MJ2 and have been thinking about selling that to get a Ha6a. I have nothing but footscrays 4033s and would hate to have to waste those if the HA6a dont work with 12at7.
> 
> Thank you


No as far as I'm aware. Only 12au7.


----------



## krude

Some tube rolling impressions time : 
12AU7 : 
Electroharmonix - flat, smooth, detailed. Seems like a very safe and potentially boring choice. Can mix well with more spicy power tubes to rein them in a bit.
Gold Lion - spicy, saturated mids, deep bass boost, a lot of treble. Coloured and contoured. Can be too much for sharp sets especially if combined with coloured power tubes. Combining this with KT88 is too much for 1266 TC for example especially for tracks with sharper treble, but spices up Susvara just right. YMMV.

EL34 : 
Shuguang Black Treasure (6ca7-z) - very mellow tube, smooth and relatively detailed with sweet flavour. My pair has issues with UL mode and produces a static noise on some sets with UL. Probably my least favourite but could be good if you look for mellow sweet sound.
Electroharmonix - dry, detailed, smooth, safe. Combined with Electroharmonix 12AU7 has a very dry, safe and analytical presentation that works very well (at least very interesting) with analytical sets like 1266 TC. It could be my main driver for the TC.
Gold Lion (KT77) - A spicier and more coloured version of the Electroharmonix. Still smooth and relatively safe but with a bit more colour, body and bottom. I like this a lot. Works very well with Gold Lion 12AU7 and offsets some of it's sharpness creating a nice blend.

KT88 : 
Electroharmonix - spacious, detailed, relatively dry, smooth and relatively safe. I like it a lot. Like Gold Lion KT77 works great with GL 12AU7, which is one of my favourite combos at the moment.
Gold Lion - very detailed, lots of bass, treble, v shaped and coloured. Could work ok with a more mellow and safe 12AU7. Combining with GL 12AU7 overdoes the sharpness and bass for me. This combo is very entertaining and if your music is very well recorded and very smooth it will give it a lot of life, but if there is any sharpness in your material it will make it unbearable on sharper sets like the TC or even Susvara. Works quite well on Utopia though which seems to be a lot more forgiving in the treble. 

So TL;DR my fav combos so far are : 
GL 12AU7 -> Electroharmonix KT88 and GL 12AU7 -> GL KT77

The differences between the tubes are very pronounced and you can get a lot of variety seeing how different combinations respond to TR and UL modes as well as impedance levels.


----------



## ArkNerevar (Jul 5, 2022)

krude said:


> Shuguang Black Treasure (6ca7-z) - very mellow tube, smooth and relatively detailed with sweet flavour. My pair has issues with UL mode and produces a static noise on some sets with UL. Probably my least favourite but could be good if you look for mellow sweet sound.


This is very interesting for me, I have been considering the Psvane 6CA7 Tii, Shuguang Black Treasures are no longer available anywhere so was looking at Psvanes offerings, I have heard it said that Psvanes T series is very similar to Shuguang Black Treasure series of tubes, do you have any experiance between the two? does anyone in general have any experiance between Psvanes and Shuguangs?, could you go into any more detail about the sound krude? overly mellow & smooth is not a sound I want to go for, my verite is smooth & mellow enough as it is, if the two Chinese 6CA7 offerings are alike then thats a pass from me, so you could have saved me some cash, cheers mate.


----------



## Mansinthe86

As someone that never had a tube amp before I'm considering a used HA-6A or a the upcoming 3A they I would like to use with planar magnetic headphones.

But is there something I should know in particular about maintaining a tube amp and cost for tubes that I should consider? 

I have no idea what tubes are better for what use case exactly or how expensive a replacement set would be.


----------



## fanteskiller

krude said:


> Some tube rolling impressions time :
> 12AU7 :
> Electroharmonix - flat, smooth, detailed. Seems like a very safe and potentially boring choice. Can mix well with more spicy power tubes to rein them in a bit.
> Gold Lion - spicy, saturated mids, deep bass boost, a lot of treble. Coloured and contoured. Can be too much for sharp sets especially if combined with coloured power tubes. Combining this with KT88 is too much for 1266 TC for example especially for tracks with sharper treble, but spices up Susvara just right. YMMV.
> ...


Great review


----------



## krude

Mansinthe86 said:


> As someone that never had a tube amp before I'm considering a used HA-6A or a the upcoming 3A they I would like to use with planar magnetic headphones.
> 
> But is there something I should know in particular about maintaining a tube amp and cost for tubes that I should consider?
> 
> I have no idea what tubes are better for what use case exactly or how expensive a replacement set would be.


Check prices of 12au7 el34 / kt77 / kt88 online. Tubes will work for 1000s of hours of playback, so the only cost is rolling them to change the tuning, and it can change the sound dramatically.

It has good power for planars, can even drive Susvara albeit at peak power.


----------



## youfkndonkey

Did Cayin stop shipping these with Genalex Golden Lion KT88's? My local distributor is saying they only come with EL34's now.


----------



## ThanatosVI (Jul 26, 2022)

youfkndonkey said:


> Did Cayin stop shipping these with Genalex Golden Lion KT88's? My local distributor is saying they only come with EL34's now.


Yes, higher price less tubes in the Base package


----------



## youfkndonkey

ThanatosVI said:


> Yes, higher price less tubes in the Bass package


ahh right, makes sense, can't imagine there's a lot of tubes getting exported out of Russia at the moment.


----------



## ThanatosVI

youfkndonkey said:


> ahh right, makes sense, can't imagine there's a lot of tubes getting exported out of Russia at the moment.


And those that do, cost more.
JJ is terribly overwhelmed with orders, so not enough supply from them either


----------



## Andykong

youfkndonkey said:


> Did Cayin stop shipping these with Genalex Golden Lion KT88's? My local distributor is saying they only come with EL34's now.



Unfortunately, yes.  The HA-6A will only come with one set of the EL34 output tubes.  We have to revise our HA-6A package in view of the recent supply chain crisis and repaid price increase of key components in the past 6 months.  



ThanatosVI said:


> And those that do, cost more.
> JJ is terribly overwhelmed with orders, so not enough supply from them either



Yes, we are struggling, we need to secure ample stock from JJ for our HA-3A.  Almost mission impossible at this moment.


----------



## jarvincassidy

ungauged said:


> Got a really good deal on a HA-6A which I could not resist. While it does have some slight hiss/hum from the VO, it's dead quiet on the HEKse.
> 
> Been giving my trusty HA-2SE and the HA-6A a good detailed A/B.


Hi, i know this is an old post, but can you give impressions of how these 2 amps compared?


----------



## ungauged

jarvincassidy said:


> Hi, i know this is an old post, but can you give impressions of how these 2 amps compared?


Having owned them for some time now. Had multiple friends over to test them too. We all pretty much have the same conclusion demoing them with both a variety of headphones. (HEKse, VO, HD800s and LCD X)

The HA-6A has a tad larger soundstage with slightly more dynamics. Granted its fitted with Psvane KT88-Tii and Genalex Gold Lions in them. Personally prefer it on triode for the kind of music I listen to. Linear for really critical listening but can be fatiguing if paired with a the HEKse.

The HA-2SE has an overall warmer tonal signature all round. Great for my HEKse which has a tendency to sound slightly too trebly for my liking on certain tracks. It’s fitted with a Brimar 12au7. 

I guess it really depends on what tonality you are looking for. With that said, of course the HA-6A is more versatile. I really can’t give you a better description for the Auris other than “relaxing”.

Hope my description makes any sense.


----------



## krude (Aug 21, 2022)

Just an appreciation post here, running May -> Ferrum Oor + Hypsos (as a pre) -> HA6a (Gold Lion 12au7 and Electroharmonix KT88) -> Mackie HR824mk2 studio monitors via balanced out and it sounds sublime. Full 20 - 20, smooth and ultra detailed treble, great holographic midrange and thundering bass down to the bassment xD one of those unexpected combinations that sounds way better than I would ever give it credit to.


----------



## Mansinthe86

krude said:


> Just an appreciation post here, running May -> Ferrum Oor + Hypsos (as a pre) -> HA6a (Gold Lion 12au7 and Electroharmonix KT88) -> Mackie HR824mk2 studio monitors via balanced out and it sounds sublime. Full 20 - 20, smooth and ultra detailed treble, great holographic midrange and thundering bass down to the bassment xD one of those unexpected combinations that sounds way better than I would ever give it credit to.


Gotta post a picture or it didn't happen


----------



## krude

Mansinthe86 said:


> Gotta post a picture or it didn't happen


Lol, ok but still waiting for furniture in the new flat 😂


----------



## jarvincassidy

ungauged said:


> Having owned them for some time now. Had multiple friends over to test them too. We all pretty much have the same conclusion demoing them with both a variety of headphones. (HEKse, VO, HD800s and LCD X)
> 
> The HA-6A has a tad larger soundstage with slightly more dynamics. Granted its fitted with Psvane KT88-Tii and Genalex Gold Lions in them. Personally prefer it on triode for the kind of music I listen to. Linear for really critical listening but can be fatiguing if paired with a the HEKse.
> 
> ...


Thanks for the short description. That helps a lot in my decision making, since there is no way for me to audition the 2 amps side by side.


----------



## Andykong

krude said:


> Just an appreciation post here, running May -> Ferrum Oor + Hypsos (as a pre) -> HA6a (Gold Lion 12au7 and Electroharmonix KT88) -> Mackie HR824mk2 studio monitors via balanced out and it sounds sublime. Full 20 - 20, smooth and ultra detailed treble, great holographic midrange and thundering bass down to the bassment xD one of those unexpected combinations that sounds way better than I would ever give it credit to.


I suppose you custom make a 4.4mm to dual XLR3 cable to connect the 4.4mm headphone output of HA-6A to your Mackie? A very interesting setup, something we didn't have in our mind when we design the HA-6A, glad it works out fine for you.


----------



## Andykong

Mid-Autumn Festival is held on the full moon of the 8th month of the lunar calendar.  In Chinese Culture, roundness symbolizes completeness and togetherness, therefore, the Mid-Autumn Festival is a time for friends and family to come together and appreciate the union and completeness of our life.  This might be a small wish that we take for granted in the past, but COVID has taught us to treasure every moment of gathering and reunion, and we wish all our users and friend a Happy Mid-Autumn Festival.

I want to share a personal plan with all my partners and friends in HeadFi forum.  I'll take a long break later this month, and this will probably last till the end of 2022.  I'll stay out of the radar completely and will resurface when I feel confident that I am fit to handle my job again. @Cayin will take over my role for Cayin audio and I'll hand over my ongoing activities and responsibilities to them gradually next week.   So if you need to PM me on a Cayin-related issue, please include or address your problem to @Cayin.  I really enjoy my time with the HeadFi forum and am looking forward to meeting with you again after my long vacation.


----------



## krude

Andykong said:


> Mid-Autumn Festival is held on the full moon of the 8th month of the lunar calendar.  In Chinese Culture, roundness symbolizes completeness and togetherness, therefore, the Mid-Autumn Festival is a time for friends and family to come together and appreciate the union and completeness of our life.  This might be a small wish that we take for granted in the past, but COVID has taught us to treasure every moment of gathering and reunion, and we wish all our users and friend a Happy Mid-Autumn Festival.
> 
> I want to share a personal plan with all my partners and friends in HeadFi forum.  I'll take a long break later this month, and this will probably last till the end of 2022.  I'll stay out of the radar completely and will resurface when I feel confident that I am fit to handle my job again. @Cayin will take over my role for Cayin audio and I'll hand over my ongoing activities and responsibilities to them gradually next week.   So if you need to PM me on a Cayin-related issue, please include or address your problem to @Cayin.  I really enjoy my time with the HeadFi forum and am looking forward to meeting with you again after my long vacation.


Take care, have a good time off  we all need it from time to time 🍻


----------



## lightoflight

Hi, can someone recommend some tubes that are good for electronic music? Since the new units does not come with KT88, I'm wondering what I need to get for it to be up to my liking (bass and soundstage).


----------



## krude

lightoflight said:


> Hi, can someone recommend some tubes that are good for electronic music? Since the new units does not come with KT88, I'm wondering what I need to get for it to be up to my liking (bass and soundstage).


Hmm I would try Genalex Gold Lion KT88 and KT77 (EL34), you can also try Genalex 12au7. Problem is that Gold Lion KT88 and 12au7 give mire of a V shape, so along with more bass you'll get more treble. I use their KT77 at the moment with Electroharmonix 12au7 and it gives more bass but still cobtrolled treble. You can swap 12au7 for Gold Lions as well to get even more bass and a bit of a treble spike.

There's also Mullard and Psvane but I haven't tried them yet.


----------



## Newbman123

krude said:


> Hmm I would try Genalex Gold Lion KT88 and KT77 (EL34), you can also try Genalex 12au7. Problem is that Gold Lion KT88 and 12au7 give mire of a V shape, so along with more bass you'll get more treble. I use their KT77 at the moment with Electroharmonix 12au7 and it gives more bass but still cobtrolled treble. You can swap 12au7 for Gold Lions as well to get even more bass and a bit of a treble spike.
> 
> There's also Mullard and Psvane but I haven't tried them yet.


Has anyone tried the rca clear top 12au7? I was considering getting a matched pair of those.


----------



## krude

Newbman123 said:


> Has anyone tried the rca clear top 12au7? I was considering getting a matched pair of those.


I haven't. Give it a go and report your findings please. HA6a doesn't stop surprising me with just how refined and fun it can sound and there's still a lot of rolling to do


----------



## lightoflight

krude said:


> Hmm I would try Genalex Gold Lion KT88 and KT77 (EL34), you can also try Genalex 12au7. Problem is that Gold Lion KT88 and 12au7 give mire of a V shape, so along with more bass you'll get more treble. I use their KT77 at the moment with Electroharmonix 12au7 and it gives more bass but still cobtrolled treble. You can swap 12au7 for Gold Lions as well to get even more bass and a bit of a treble spike.
> 
> There's also Mullard and Psvane but I haven't tried them yet.


Thanks for your response.

I bought some Mullard KT88 to try out.


----------



## krude

lightoflight said:


> Thanks for your response.
> 
> I bought some Mullard KT88 to try out.


Nice, let us know how you like it


----------



## busseysound

Newbman123 said:


> Has anyone tried the rca clear top 12au7? I was considering getting a matched pair of those.


I have - they're quite good.  Impressive clarity and usually not too expensive.


----------



## krude

busseysound said:


> I have - they're quite good.  Impressive clarity and usually not too expensive.


Did you compare them to Electroharmonix or Gold Lions? Or anything else for that matter


----------



## busseysound

krude said:


> Did you compare them to Electroharmonix or Gold Lions? Or anything else for that matter


I've rolled through a crazy number of 12AU7's (or ECC81's for that matter when I owned an MJ2).  Here's a list of some of them:

RFT ECC82 folded tabs on plate
Philips white lettering SQ (although I believe it's an ECC81)
Sylvania 12AU7, long black plate (best) 12AU7WA, 12AT7
RCA 5814A, 5963, 12AU7 clear top, 12AU7A
Tungsram ECC82, ECC81(black plate on the ECC82 is much better than gray plate)
Baldwin 12AU7
Amperex 6DJ8 orange lettering
Tesla ECC802S
Brimar CV455

All I can think of at the moment.  Keep in mind some of those were on the MJ2 and won't work in the Cayin.  The outstanding winner on that list is the Tesla ECC802S but is usually pretty expensive.  My end game at some point will be the Telefunken ECC802S but I'll have to find them at a decent price.  The Sylvania 12AU7 long black plate is a great tube (good balance and clarity) along with the 12AU7 clear top. Transparency is always a major priority for me.  Hope that helps some.


----------



## Newbman123

busseysound said:


> I've rolled through a crazy number of 12AU7's (or ECC81's for that matter when I owned an MJ2).  Here's a list of some of them:
> 
> RFT ECC82 folded tabs on plate
> Philips white lettering SQ (although I believe it's an ECC81)
> ...


Which did you feel were the most dynamic of the lot?


----------



## busseysound

Newbman123 said:


> Which did you feel were the most dynamic of the lot?


Tesla ECC802S for sure.  Wish the cost on those was lower.


----------



## krude

busseysound said:


> Tesla ECC802S for sure.  Wish the cost on those was lower.


Nice one, thanks for the info. Did you also roll any EL34 or KT88?


----------



## busseysound

krude said:


> Nice one, thanks for the info. Did you also roll any EL34 or KT88?


A few KT88.  KR was pretty darn nice, but I did quite a bit of research and the Tesla Vrsovice (black base) was highly recommended for transparency and it's fantastic (was difficult to find though).  It's so good I don't feel the need to try anything else.  From what I understand the E.A.T. is the remake with much better construction (but crazy expensive).  My HA-6A only came with the Electroharmonix EL34 so I'd like to try the Gold Lion KT88's sometime.


----------



## krude

busseysound said:


> A few KT88.  KR was pretty darn nice, but I did quite a bit of research and the Tesla Vrsovice (black base) was highly recommended for transparency and it's fantastic (was difficult to find though).  It's so good I don't feel the need to try anything else.  From what I understand the E.A.T. is the remake with much better construction (but crazy expensive).  My HA-6A only came with the Electroharmonix EL34 so I'd like to try the Gold Lion KT88's sometime.


I tried the KRs briefly and found them shouty at the time, but I was quite new to tubes back then, just got the HA6a and also the rest of my stack wasn't really on point so my experience probably doesn't count. I'll have to give Teslas a shot for sure 🍻


----------



## lightoflight

I'm a new user here and I didn't think the EL-34 would fit my taste before receiving it. It sounds good so far; excellent sub-bass but just wish it was more textured.


----------



## Lapinata

lightoflight said:


> I'm a new user here and I didn't think the EL-34 would fit my taste before receiving it. It sounds good so far; excellent sub-bass but just wish it was more textured.


Welcome to the club 

A power amp like KT88 or 6550 is probably your way to go if you are looking for something tight and powerful. The bass gets cleaner and warmer too. 
Rolling the pre-amp tube will help the detail, resolution, and smoothness. I recommend trying to roll these lil tubes before the big ones, save some budget.

Here is my story to share. 
I'm an EL34 guy. I prefer EL34 for Jazz and Vocals. I just got Focal Elex for a month and pairing with Cayin HA-6A (EL34). It gives me goosebumps when listening to female vocals like Adele, Lucy Thomas, Diana Ross, etc. Give it a try you might love this for different occasions since this Cayin amp is super versatile after all.

PS, If you are looking for super detail, slam, punch, and thump thump, a Solid State amp may be better. It's my preference right there.


----------



## krude

lightoflight said:


> I'm a new user here and I didn't think the EL-34 would fit my taste before receiving it. It sounds good so far; excellent sub-bass but just wish it was more textured.


Congrats, you've got a nice gear collection. After a while I came to a conclusion that HA6a is a better version of the Soloist GT 😅 

From my experience the tube type doesn't matter as much. Different manufacturers have different sound and sometimes different tubes have different sound as well due to variation and burn in.

There are some good tube rolling impressions on here. If you want a bit of a v shape with good detail and extension try Gold Lion 12au7 into Gold Lion KT88. That's too much v for me tho. Generally I find tubes to be : v shaped, clean / cool (reference / safe sound) or warm. You just need to find the right combinations for your cans of choice. For example 1266 TC sounds amazingly holographic on Electroharmonix 12au7 into Electroharmonix KT88, but Susvara on same tubes is bland for me 🤔 

Good luck, have fun


----------



## lightoflight

Lapinata said:


> Welcome to the club
> 
> A power amp like KT88 or 6550 is probably your way to go if you are looking for something tight and powerful. The bass gets cleaner and warmer too.
> Rolling the pre-amp tube will help the detail, resolution, and smoothness. I recommend trying to roll these lil tubes before the big ones, save some budget.
> ...


Thank you, I'm glad to be here.

I have a pair of Mullard KT88 to try out after I burn in the EL34. So far, the EL34 is good, the bass cleans up a little bit in Ultra-linear mode. The highs are really sharp at the moment, hopefully they will roll off as time passes.

I have a pair of Elex too, I need to give them more time with this amp. But so far, I'm getting amazing synergy with the Arya V2. Normally, the Arya is wide but lack depth, now they are super wide and have added depth. In addition, the tube harmonics of this amp is great with all my headphones, human voices and analog instrument voices sounds life-like as to before they were recorded to digital format.


----------



## lightoflight

krude said:


> Congrats, you've got a nice gear collection. After a while I came to a conclusion that HA6a is a better version of the Soloist GT 😅
> 
> From my experience the tube type doesn't matter as much. Different manufacturers have different sound and sometimes different tubes have different sound as well due to variation and burn in.
> 
> ...


Come on, man. You know that's not true.  The Soloist GT is awesome.

Well, hopefully I will not turn into a tube collector. Thanks for your insight.


----------



## krude

lightoflight said:


> Come on, man. You know that's not true.  The Soloist GT is awesome.
> 
> Well, hopefully I will not turn into a tube collector. Thanks for your insight.


You'll try a few clear and detailed tube combos like Mullard and or Electroharmonix and you'll see what I mean, especially with UL and impedamce switching you can get the stage / treble where you want it. You'll get the smoothest treble in TR and lowest impedance. Also try lowering the input voltage if you have a volume in your dac or a pre. I use Oor as a pre for the HA6a (May doesn't have volume and it's really hot with 5.8v) and it works wonders in my chain.


----------



## lightoflight (Sep 17, 2022)

Hey guys, I just popped in the Mullard KT88 replacing the EH EL34, and it sounds clearer and the notes have less sustain. Overall good frequency response. The treble is not as sharp as the EL34, that's a good thing for me. I was wondering if it's safe to leave the amp running overnight.


----------



## Lapinata

lightoflight said:


> Thank you, I'm glad to be here.
> 
> I have a pair of Mullard KT88 to try out after I burn in the EL34. So far, the EL34 is good, the bass cleans up a little bit in Ultra-linear mode. The highs are really sharp at the moment, hopefully they will roll off as time passes.
> 
> I have a pair of Elex too, I need to give them more time with this amp. But so far, I'm getting amazing synergy with the Arya V2. Normally, the Arya is wide but lack depth, now they are super wide and have added depth. In addition, the tube harmonics of this amp is great with all my headphones, human voices and analog instrument voices sounds life-like as to before they were recorded to digital format.


Arya is one of my next purchase target, especially new Stealth Edition. I heard from a few Arya owners that they prefer using with SS amp, but I’m glad to hear that it paired well with this. Makes me want to go and get it to try now LOL

My end-game target will be the Meze Empyrean/Elite. Many praise from this thread. I tried demo unit from local store, gotta say I’m in love. Can’t wait to try with this amp.


----------



## lightoflight (Sep 25, 2022)

Evaluating the Gold Lion KT77 with JJ 12AU7 compared to Electro-Harmonix EL34 with JJ 12AU7.

Price paid for matched pair: $109.99 USD

Headphones used: Arya V2 and HE1000se

Right off the bat I noticed two things.

Decrease in bass quantity by 2 dB
Different tube harmonics
The Gold Lion KT77, in Ultra-Linear mode, sounds like a true solid-state Class-A amp (much better rendition than the Mullard KT88), it brought back a lot of familiarity I have with my Soloist GT with upgraded op-amps. The romantic sound of the EL34, where the notes have longer sustain and lush mid-range, is no longer present with the KT77 on board.

What we have is greatly improved:

Clarity
Transient response
Shorter sustain of musical notes
The KT77 have an extended presence that makes enthusiastic open hi-hat and crash cymbal hits have a piercing ring. EL34 suffer from this as well but not as much as the KT77.  A good remedy is equalizing down 2.5 dB at 12 kHz.

Clarity quality is well throughout the whole frequency range with just a tad more tube harmonics than the Mullard KT88.

The transient response is excellent, it gives the listener better discernment of notes and improved sense of note imaging within the headstage. At one point in my evaluation using the Arya V2, I thought I had the HE1000se on. I was very surprised to be hearing such good imaging depth with the Arya V2.  In contrast, with the EL34, melodic notes tend to be smeared and blends in with the other layers of musical notes within the song track. And as a result, the EL34 have a two-dimensional soundstage.

Personally, I prefer this sound signature because of the transient response, but I do miss the EL34 bass and lushness. Hopefully I can bring that back by rolling different 12AU7.


----------



## Lapinata

lightoflight said:


> Evaluating the Gold Lion KT77 with JJ 12AU7 compared to Electro-Harmonix EL34 with JJ 12AU7.
> 
> Price paid for matched pair: $109.99 USD
> 
> ...


TYSM for your evaluation

Btw, glad you got the good impression of EL34. I would say it’s not really 2D, but rather put yourself into audience seat instead of the standing at maestro stand. In this audience seat the sound project at you with the reverberation beside and behind you. It might just be my imagination though

You make me want to make purchase of the KT77 now, really do.
I had it on my cart last year, but I was settled after rolled the Amperex 12au7. It’s time for me to trigger it now😂


----------



## lightoflight (Sep 27, 2022)

Lapinata said:


> TYSM for your evaluation
> 
> Btw, glad you got the good impression of EL34. I would say it’s not really 2D, but rather put yourself into audience seat instead of the standing at maestro stand. In this audience seat the sound project at you with the reverberation beside and behind you. It might just be my imagination though
> 
> ...


It must be the JJ 12AU7 that's holding back the EH EL34, because I just got a pair of RCA 12AU7 clear top and the sound has much more resolution with the GL KT77. I have to try them with the EH EL34 later.


----------



## jonathan c

lightoflight said:


> It must be the JJ 12AU7 that's holding back the EH EL34, because I just got a pair of RCA 12AU7 clear top** and the sound has much more resolution with the GL KT77. I have to try them with the EH EL34 later.


** that is a wonderful 12AU7 and not an ‘arm / leg’ price !!


----------



## Toonartist

Is the HA-6A available in all black like the HA-3A?


----------



## ThanatosVI

Toonartist said:


> Is the HA-6A available in all black like the HA-3A?


No it's not


----------



## Toonartist

ThanatosVI said:


> No it's not


Shame... the HA-3A looks very smart all in black but liked the extra feature here.


----------



## ThanatosVI

Toonartist said:


> Shame... the HA-3A looks very smart all in black but liked the extra feature here.


Yeah they should make a black Ha-6a just like the HA-300. 

@Cayin  are there any plans for that in the future?


----------



## krude

12au7 rolling with GL KT88, testing with Susvara : 
- Sylvania (circa '64) - detailed tube with a softer more romantic top end and midrange but still strong bass. It's not a dark sounding tube, maybe slightly warm off neutral signature.
- RCA black plate - also really detailed tube, softer and warmer than Sylvania with good bass. This is something that I would call a warmer tube but it still has ample air for separation and details up top.

I settled on RCA black plate -> GL KT88 at the moment, running mostly in triode mode and lowest impedance with the Susvara. Probably the most relaxed and full bodied I've heard Susvara sounding to date.


----------



## lightoflight (Sep 29, 2022)

The GL KT77 finally starting to settle into its optimum sound after 100 hours. Used in conjunction with RCA 12AU7 clear top and sound is very similar to Class-A with tube harmonics (thick bass, thumping kick drums and bold forward mid-range frequencies).

GL KT77 after 100 hours:

-2 dB Bass is back to normal level
High brilliance rolled off
Holography opened up (used LCD-4z and HE1000se. HE1000se does a better job, my listening was done at 70 dB)


----------



## jandrese

After a brief email exchange with Zach from ZMF I ordered the HA-6A today. Excited to try it out and will be looking for some good KT88 tubes. Mostly, will be running the ZMF Verite Closed but also the Atrium, HiFiMan Arya Stealth, and Audeze LCD-X (2nd gen). I may add Susvara so the power was a selling point. Considered the other two Cayin amps especially the 300B. Not sure there is a wrong answer but at least the HA-6A seems more versatile. While remaining diplomatic Zach essentially recommended the HA-6A over the others for my use case.


----------



## lightoflight

jandrese said:


> After a brief email exchange with Zach from ZMF I ordered the HA-6A today. Excited to try it out and will be looking for some good KT88 tubes. Mostly, will be running the ZMF Verite Closed but also the Atrium, HiFiMan Arya Stealth, and Audeze LCD-X (2nd gen). I may add Susvara so the power was a selling point. Considered the other two Cayin amps especially the 300B. Not sure there is a wrong answer but at least the HA-6A seems more versatile. While remaining diplomatic Zach essentially recommended the HA-6A over the others for my use case.


Mullard and Gold Lion KT88 are the same, Mullard is cheaper, keep that in mind. I recommend replacing the JJ 12AU7 as soon as you can, unless you like a warm sound and flat soundstage.


----------



## Newbman123

lightoflight said:


> Mullard and Gold Lion KT88 are the same, Mullard is cheaper, keep that in mind. I recommend replacing the JJ 12AU7 as soon as you can, unless you like a warm sound and flat soundstage.


Any suggestions for the jj12au7?


----------



## busseysound

jandrese said:


> After a brief email exchange with Zach from ZMF I ordered the HA-6A today. Excited to try it out and will be looking for some good KT88 tubes. Mostly, will be running the ZMF Verite Closed but also the Atrium, HiFiMan Arya Stealth, and Audeze LCD-X (2nd gen). I may add Susvara so the power was a selling point. Considered the other two Cayin amps especially the 300B. Not sure there is a wrong answer but at least the HA-6A seems more versatile. While remaining diplomatic Zach essentially recommended the HA-6A over the others for my use case.


This is the route I went as well - even after hearing the 300B in Chicago.  I've been thrilled with the HA-6A and my VC.  Best tubes I've found are the Tesla Vrsovice KT88 and Telefunken ECC802S.  Both are quite expensive but they are truly amazing.  Tesla ECC802S yellow label (from the '60s and early '70s) are a great option to and much cheaper.


----------



## jandrese

busseysound said:


> This is the route I went as well - even after hearing the 300B in Chicago.  I've been thrilled with the HA-6A and my VC.  Best tubes I've found are the Tesla Vrsovice KT88 and Telefunken ECC802S.  Both are quite expensive but they are truly amazing.  Tesla ECC802S yellow label (from the '60s and early '70s) are a great option to and much cheaper.


Cool, thanks for the tube recommendations. There are soooooo many possible tubes I'll see how I like it out of the box first then try to decide where to go. I was poised to get the 300B but the universe had other plans.


----------



## busseysound

Has anyone tried using 17DE4 rectifier tubes instead of 22DE4?  There's a brand I would like to try but it's impossible to find the 22DE4.  I'm wondering if it's ok to use it in the HA-6A?


----------



## ArkNerevar

busseysound said:


> Has anyone tried using 17DE4 rectifier tubes instead of 22DE4?  There's a brand I would like to try but it's impossible to find the 22DE4.  I'm wondering if it's ok to use it in the HA-6A?


I am very interested in this question as well, like you I want to roll my rectifiers but cant find anything besides RCA (which is the stock) and GE


----------



## lightoflight (Oct 11, 2022)

Does anybody know if the Tung-Sol 7581A work with the HA-6A? I know the 7581A is not on the list of compatible tubes, but the description says the tube is basically a KT66 and KT66 is in the list.

@Cayin, your thoughts on this?

Datasheet PDF



> *New Plate Current Tung-Sol 7581A (KT66) Vacuum Tubes*
> 
> The Tung-Sol 7581A is rated at a higher 35 watts compared to the standard 7581 or 6L6GC. This tube is a direct substitute for the KT66, and is in fact a version of the KT66. These Tung-Sols were built to last with a very large plate structure and many heat dissipaters for reliability. The 7581A has a very warm tone and gives you much more headroom if ran in place of a standard 6L6GC.


----------



## project86

I've been out of this thread for a while but still using/loving the HA-6A. I've been running some classic Amperex Bugle Boy 12AU7 long plates that I stole from my HA-1A mk2, and am currently back on the Gold Lion KT88s while I wait for some others to arrive. I actually quite like the stock Genelex glass overall, and would recommend focusing on the 12AU7s first as those are the weak link (same thing happened in the HA-1A mk2 as well).

I wanted to pop in and mention that Cayin has a new high-end DAC out - the CS-100DAC:






I just started a thread about it if anyone is interested. It makes an exceptional match with the HA-6A, though honestly it should pair well with most anything given the selectable tube/solid state output options. Definitely worth a look if anyone is in the market for a quality DAC to match their HA-6A. ZMF sells them on his site, and is a big fan as well.


----------



## shafat777

I am on the fence about buying this amp. I was wondering if anyone from here or ZMF know if this amp will take any 12at7 tubes or is it strictly 12au7? Over the last two years, i have collected a plethora of rare and almost unobtainium 12at7 tubes (for my MJ2 and LP) and would hate to have to sell those and restock on 12au7s.  I would be willing to sell my cap modded MJ2 and but i am really hesitant to sell the tubes since they are getting more difficult to find these days. 

Any information would be helpful. Thank you


----------



## busseysound

shafat777 said:


> I am on the fence about buying this amp. I was wondering if anyone from here or ZMF know if this amp will take any 12at7 tubes or is it strictly 12au7? Over the last two years, i have collected a plethora of rare and almost unobtainium 12at7 tubes (for my MJ2 and LP) and would hate to have to sell those and restock on 12au7s.  I would be willing to sell my cap modded MJ2 and but i am really hesitant to sell the tubes since they are getting more difficult to find these days.
> 
> Any information would be helpful. Thank you


I have only tried the 12AU7 (afraid to try my 12AT7).  In their manual they show different options for each slot, but for 12AU7 they don't show any other options.  Might want to contact Cayin directly, but I believe 12AU7 is the limit.


----------



## project86

I feel like I've heard 12AT7 was not recommended, but I could be mistaken.

With Andy Kong on vacation through the end of the year, I'm not sure there will be any answer forthcoming. That guy is insanely helpful but he can't be everywhere at once, and I don't think Cayin has a backup for when he isn't around.


----------



## krude

shafat777 said:


> I am on the fence about buying this amp. I was wondering if anyone from here or ZMF know if this amp will take any 12at7 tubes or is it strictly 12au7? Over the last two years, i have collected a plethora of rare and almost unobtainium 12at7 tubes (for my MJ2 and LP) and would hate to have to sell those and restock on 12au7s.  I would be willing to sell my cap modded MJ2 and but i am really hesitant to sell the tubes since they are getting more difficult to find these days.
> 
> Any information would be helpful. Thank you


I asked that question once, and got "strictly 12AU7" answer.


----------



## ThanatosVI

shafat777 said:


> I am on the fence about buying this amp. I was wondering if anyone from here or ZMF know if this amp will take any 12at7 tubes or is it strictly 12au7? Over the last two years, i have collected a plethora of rare and almost unobtainium 12at7 tubes (for my MJ2 and LP) and would hate to have to sell those and restock on 12au7s.  I would be willing to sell my cap modded MJ2 and but i am really hesitant to sell the tubes since they are getting more difficult to find these days.
> 
> Any information would be helpful. Thank you


Electrically it would work, it would not damage the amp, BUT the amplification factor is totally different. 
It could be either a lot louder or quieter (don't remember which one had the greater amplification factor)
The 12au7 also deliver a lot more current, which means you could run out if juice with the 12AT7

Disclaimer: dangerous half knowledge on my side.


----------



## shafat777

ThanatosVI said:


> Electrically it would work, it would not damage the amp, BUT the amplification factor is totally different.
> It could be either a lot louder or quieter (don't remember which one had the greater amplification factor)
> The 12au7 also deliver a lot more current, which means you could run out if juice with the 12AT7
> 
> Disclaimer: dangerous half knowledge on my side.


I hear ya. 12at7 would be louder because it has a higher amplification. At least thats how it is with my cap modded MJ2. The Mj2 with 12at7 tubes sound way better than any 12au7 tubes. I think i m just gonna have to turn over all of my 12at7 tubes and either sell or trade them for 12au7 variants. Thank you @krude and @ThanatosVI for the info.


----------



## lightoflight

lightoflight said:


> Does anybody know if the Tung-Sol 7581A work with the HA-6A? I know the 7581A is not on the list of compatible tubes, but the description says the tube is basically a KT66 and KT66 is in the list.
> 
> @Cayin, your thoughts on this?
> 
> Datasheet PDF


I got word from Cayin customer support that it is okay to use the Tung-Sol 7581A.


----------



## jandrese

The Cayin HA-6A amp, where to begin? I bought it just to see if maybe it might sound better than or offer something different than my Schiit Lyr3. After 10 seconds of listening I was like, Lyr3 who, I knew I'd entered another league.

There are so many possible configurations I'll just give the big picture overview here. Back in the day I heard the Audio Research Reference 600 monoblock power amps. They were sublime. This headphone amp recapitulates that experience. Effortless power, detail, clarity, and a physicality heretofore unknown in my headphone experience. The sound is gorgeous, it makes you weak in the knees, it's so darn good you want to listen more and more. 

Imagine an amp that has all the right circuitry to pull all the detail out of recordings, to reveal subtle textures and reverb, and to cohesively present music from the sub bass through the highs. Then give it a massive surplus of power, so much power that no part of the sonic experience is left wanting. The music flows in and says there are lush vocals here--the amp says no problem. Strings too--no problem. Dynamic bass lines and drums--no problem. Delicate reverb--no problem. No problem, I have resources to spare, I'm a HA-6A. 

The stock configuration is excellent. Wanna swap tubes? If you replace the EL34 with KT88 I recommend counterbalancing that with a softer 12au7 driver tube. The tubes compliment each other or can reinforce strengths. The stock drivers with the KT88s was too...too much for me so I backed off the Gold Lion KT88s with the Baldwin 12au7 drivers included in the package from ZMF. That is, I believe, the combination preferred by Zach. 

My favorite headphone, and my favorite with this amp, is the ZMF Verite Closed. I use the high Z setting and the 4.4 mm balanced jack because I have a nice replacement cable from Apos. Also, the 4.4 mm jack is supposed to have a resistor (I think) to reduce the sound output. By 9 o'clock on the volume knob the sound level is intense. Normally, I use the Topping D90se as a preamp of sorts to give the amps volume knob some range. In the stock tube configuration there is some background noise using the ZMF Verite Closed. Less with other headphones and none with Hifiman Arya Stealth. 

Anyway, awesome amp. Sublime.


----------



## shafat777

Just pulled the trigger on the HA-6A from Zmf. I cant contain the excitement. As a result, I'm gonna have to part ways with my cap modded Mjolnir 2. However, I am also elated by the idea of tuberolling with this amp. The mj2 has plenty of power, but I hear that the cayin amp is more musical and has better sound production. Estimated delivery is Monday 24th.  

Anyways, thank you Zach and ZMF for such excellent customer service and lightning fast shipping.


----------



## ThanatosVI

shafat777 said:


> Just pulled the trigger on the HA-6A from Zmf. I cant contain the excitement. As a result, I'm gonna have to part ways with my cap modded Mjolnir 2. However, I am also elated by the idea of tuberolling with this amp. The mj2 has plenty of power, but I hear that the cayin amp is more musical and has better sound production. Estimated delivery is Monday 24th.
> 
> Anyways, thank you Zach and ZMF for such excellent customer service and lightning fast shipping.


Looking forward to the Ha-6a and Elise comparisons.


----------



## busseysound

shafat777 said:


> Just pulled the trigger on the HA-6A from Zmf. I cant contain the excitement. As a result, I'm gonna have to part ways with my cap modded Mjolnir 2. However, I am also elated by the idea of tuberolling with this amp. The mj2 has plenty of power, but I hear that the cayin amp is more musical and has better sound production. Estimated delivery is Monday 24th.
> 
> Anyways, thank you Zach and ZMF for such excellent customer service and lightning fast shipping.


The MJ2 is what I was using before the HA-6A. The MJ2 is a good amp, but you'll love (and instantly hear the difference) the HA-6A. If you need some good 12AU7's I've got a couple of the old ECC802S Tesla's (yellow text) from the '60s.  I rolled A LOT of 12AU7's but liked the Tesla the best.  That is until I broke down and bought the Telefunken ECC802's.  Try the Baldwin's first though that Zach will probably send you with the amp. They're pretty great too.


----------



## shafat777

busseysound said:


> The MJ2 is what I was using before the HA-6A. The MJ2 is a good amp, but you'll love (and instantly hear the difference) the HA-6A. If you need some good 12AU7's I've got a couple of the old ECC802S Tesla's (yellow text) from the '60s.  I rolled A LOT of 12AU7's but liked the Tesla the best.  That is until I broke down and bought the Telefunken ECC802's.  Try the Baldwin's first though that Zach will probably send you with the amp. They're pretty great too.


Thank you good sir. I will definitely let you know if I'm in dire need of some 12au7s


----------



## shafat777

A quick question regarding rectifier tubes. It seems that 22DE4 type of tube almost non existent. Are there any equivanet types of tubes that can be used? I have been searching through every tube website and found maybe 2 sets for sale. What are the general consensus about this? KT88/EL34 and 12au7 tubes are abundant but the rectifiers seem rare


----------



## busseysound

shafat777 said:


> A quick question regarding rectifier tubes. It seems that 22DE4 type of tube almost non existent. Are there any equivanet types of tubes that can be used? I have been searching through every tube website and found maybe 2 sets for sale. What are the general consensus about this? KT88/EL34 and 12au7 tubes are abundant but the rectifiers seem rare


I just got word back from Cayin the other day that 22DE4 is the only option.  GE's vintage 22DE4 is a GREAT option though and not very expensive.  I was able to get a pair on eBay.


----------



## Newbman123

busseysound said:


> I just got word back from Cayin the other day that 22DE4 is the only option.  GE's vintage 22DE4 is a GREAT option though and not very expensive.  I was able to get a pair on eBay.


Do they make a sonic difference?


----------



## busseysound

Newbman123 said:


> Do they make a sonic difference?


Yes I didn't expect it, but there is a slightly better soundstage and a bit more clarity.


----------



## jonathan c

busseysound said:


> I just got word back from Cayin the other day that 22DE4 is the only option**.  GE's vintage 22DE4 is a GREAT option though and not very expensive.  I was able to get a pair on eBay.


**  😒 That takes the HA-6A (and HA-300 MK-II) off the list for me.


----------



## shafat777

jonathan c said:


> **  😒 That takes the HA-6A (and HA-300 MK-II) off the list for me.


I didn't realize just how difficult it is to find these rectifier tubes. Kt88 and 12au7s are plentiful but the 22de4s are nowhere to be found. Maybe I need to look more but so far, I have yet to see a pair, they are usually in singles


----------



## jonathan c

shafat777 said:


> I didn't realize just how difficult it is to find these rectifier tubes. Kt88 and 12au7s are plentiful but the 22de4s are nowhere to be found. Maybe I need to look more but so far, I have yet to see a pair, they are usually in singles.


•  There are many choices of rectifiers in the 5U4G + related categories. Why the 22DE4 is used / the rectification circuit is specified around the 22DE4 is beyond me.
•  Granted, I am not an EE. But saddling the HA-6A with an esoteric rectifier - from a product viewpoint - is akin to sporting a ball & chain in a sprint against Carl Lewis….😳


----------



## shafat777

Tis burning in


----------



## Newbman123

shafat777 said:


> Tis burning in


Looking amazing 😁. How do you like them compared to your gsx mini?


----------



## shafat777 (Oct 25, 2022)

You guys run any ZMF headphones with your HA-6A? I jsut fired up my Auteur classic and so far theres a lot of noise/hiss using the 4 pin xlr out and medium/high impedance settings? Can anyone please shed some light with your experience? Its dead silent on planars.


----------



## Newbman123

shafat777 said:


> You guys run any ZMF headphones with your HA-6A? I jsut fired up my Auteur classic and so far theres a lot of noise/hiss using the 4 pin xlr out and medium/high impedance settings? Can anyone please shed some light with your experience? Its dead silent on planars.


I run my atrium off of them and on high there's a noticeable tube hum. On medium it's there but not so noticeable. It's more apparent when you aren't playing music, it's not noticeable while playing music


----------



## shafat777

Newbman123 said:


> Looking amazing 😁. How do you like them compared to your gsx mini?


Its not really a fair comparison but i will still briefly explain. The gsx mini is fairly close to neutral. So i use it to listen to my headphones without any coloration, being solid state, the gsx mini delivers the signal untouched. Once i get a sense of the sound signature of the headphone, then i introduce my tube amps to the listening. The mini sounds farily neutral to me with great depth and decent soundstage. It leans slightly warm.


----------



## busseysound

shafat777 said:


> You guys run any ZMF headphones with your HA-6A? I jsut fired up my Auteur classic and so far theres a lot of noise/hiss using the 4 pin xlr out and medium/high impedance settings? Can anyone please shed some light with your experience? Its dead silent on planars.


Yep I have a bit of this - even with what I consider to be high end tubes.  Not noticeable at all when playing music - even through very quiet passages.


----------



## ungauged (Oct 26, 2022)

shafat777 said:


> You guys run any ZMF headphones with your HA-6A? I jsut fired up my Auteur classic and so far theres a lot of noise/hiss using the 4 pin xlr out and medium/high impedance settings? Can anyone please shed some light with your experience? Its dead silent on planars.


I used to have quite a noticeable hiss/hum even on M gain on my VO back in my old house and just like you, my planar HEKse ran silent and it annoyed the crap out of me. My PC and router was in close proximity to the amp.

After moving to my new place and changing my setup slightly (my setup is no longer connected to my PC and now uses a streamer or Ipad) plus moving the HA-6A on a dedicated shelf about 2 meters away from my PC. It has all disappeared even on H gain even when no music is playing.


----------



## shafat777

ungauged said:


> I used to have quite a noticeable hiss/hum even on M gain on my VO back in my old house and just like you, my planar HEKse ran silent and it annoyed the crap out of me. My PC and router was in close proximity to the amp.
> 
> After moving to my new place and changing my setup slightly (my setup is no longer connected to my PC and now uses a streamer or Ipad) plus moving the HA-6A on a dedicated shelf about 2 meters away from my PC. It has all disappeared even on H gain even when no music is playing.


I may have to give this a shot. The amp is pretty close to my gaming PC but I have everything hooked up to a ddc so any ground loop or dirty signal shouldn't be a problem


----------



## iamdman

Hello,

I have been looking for a tube amplifier for my HD800s and ZMF VC for quite some time. I am inching towards Cayin HA-6A and my rig is Roon Nucleus > MScaler > TT2. Will HA6 be a good option or is there any other tube amp I must also be considering in that price range? I like the Amp out of TT2 as it is and so dont want to get any SS amp and have tube. I am not much into tube rolling etc and I would likely stick to the stock tubes - I think!

Appreciate any inputs! 

Thanks


----------



## ThanatosVI

iamdman said:


> Hello,
> 
> I have been looking for a tube amplifier for my HD800s and ZMF VC for quite some time. I am inching towards Cayin HA-6A and my rig is Roon Nucleus > MScaler > TT2. Will HA6 be a good option or is there any other tube amp I must also be considering in that price range? I like the Amp out of TT2 as it is and so dont want to get any SS amp and have tube. I am not much into tube rolling etc and I would likely stick to the stock tubes - I think!
> 
> ...


For those high impedance dynamics you should definitely look into the Feliks Euforia as well.


----------



## iamdman (Nov 3, 2022)

***deleted***

sorry wrong forum.


----------



## AudioPowerHead

shafat777 said:


> I may have to give this a shot. The amp is pretty close to my gaming PC but I have everything hooked up to a ddc so any ground loop or dirty signal shouldn't be a problem


Have you solved the hiss/hum issue? If so, was the identified root cause due to external factors I.e power sources, nearby computer/routers or the amp itself (high noise floor) ?

Am keen on the HA-6A but this seems to be a perennial issue that has been highlighted by others frequently in this thread. I have mainly high impedance dynamic ZMF headphones so if I do get it, will likely be using xlr and settings of m/h impedance. Thanks.


----------



## Newbman123

AudioPowerHead said:


> Have you solved the hiss/hum issue? If so, was the identified root cause due to external factors I.e power sources, nearby computer/routers or the amp itself (high noise floor) ?
> 
> Am keen on the HA-6A but this seems to be a perennial issue that has been highlighted by others frequently in this thread. I have mainly high impedance dynamic ZMF headphones so if I do get it, will likely be using xlr and settings of m/h impedance. Thanks.


You really don't need to go balanced. The amp has enough power on se and is quiet enough in se mode


----------



## 19844

I tested ifi iematch 4.4 with Cayin HA-6A+ZMF verite. its work very well no more noise even noisy tube. I tried to listen if iematch made sound quality drop but I could not detect it maybe my ears not good enough


----------



## shafat777

AudioPowerHead said:


> Have you solved the hiss/hum issue? If so, was the identified root cause due to external factors I.e power sources, nearby computer/routers or the amp itself (high noise floor) ?
> 
> Am keen on the HA-6A but this seems to be a perennial issue that has been highlighted by others frequently in this thread. I have mainly high impedance dynamic ZMF headphones so if I do get it, will likely be using xlr and settings of m/h impedance. Thanks.


Yes a simple 4.4mm to 4 pin xlr adapter fixed the issue about 95% for me. The noise is completely gone with my planars. Theres a slight hum with zmf cans but its on the same level with my Elise OTL when i use kt88 + Vt231 tube combo. Its well within acceptable level for me. This amp is wonderful regarding the slight hum/noise floor with dynamic headphones when used with the 4.4m setup. Zach also recommends a preamp and set a low gain before feeding the  HA6A. For me that was not an option and so i chose the 4.4 mm route. Since i never owned a single 4.4 mm cable of any sort, I purchased a 4.4mm to xlr adapter from ZMF. Now my noise issue is all but gone. Also, in case you haven't tried it, give some new production tubes a shot, especially in the power tubes. 

Tube rolling is really fun and so far has been a wonderful experience messing with kt88 and 12au7 tubes. Over at the HA3A amp page, i just read that that amp can take ECC80 tubes in the driver slot and cayin has personally said the amp can handle the power. Would it work with our HA6A amp? @zach915m can you plz comment on this? Have you tried any other tubes besides 12au7?


----------



## shafat777

19844 said:


> I tested ifi iematch 4.4 with Cayin HA-6A+ZMF verite. its work very well no more noise even noisy tube. I tried to listen if iematch made sound quality drop but I could not detect it maybe my ears not good enough


This would be absolutely perfect for me if the headpohone end was XLR balanced instead of 3.5 mm.


----------



## AudioPowerHead

Newbman123 said:


> You really don't need to go balanced. The amp has enough power on se and is quiet enough in se mode


Yup se connection between dac and amp makes sense as HA-6A is not a push-pull balanced design amp. However on the headphone side, I think it will probably still be better to use xlr so that the output transformers are being utilized.


----------



## AudioPowerHead

19844 said:


> I tested ifi iematch 4.4 with Cayin HA-6A+ZMF verite. its work very well no more noise even noisy tube. I tried to listen if iematch made sound quality drop but I could not detect it maybe my ears not good enough


Good to know about this backup option. Thanks for sharing !


----------



## AudioPowerHead

shafat777 said:


> Yes a simple 4.4mm to 4 pin xlr adapter fixed the issue about 95% for me. The noise is completely gone with my planars. Theres a slight hum with zmf cans but its on the same level with my Elise OTL when i use kt88 + Vt231 tube combo. Its well within acceptable level for me. This amp is wonderful regarding the slight hum/noise floor with dynamic headphones when used with the 4.4m setup. Zach also recommends a preamp and set a low gain before feeding the  HA6A. For me that was not an option and so i chose the 4.4 mm route. Since i never owned a single 4.4 mm cable of any sort, I purchased a 4.4mm to xlr adapter from ZMF. Now my noise issue is all but gone. Also, in case you haven't tried it, give some new production tubes a shot, especially in the power tubes.
> 
> Tube rolling is really fun and so far has been a wonderful experience messing with kt88 and 12au7 tubes. Over at the HA3A amp page, i just read that that amp can take ECC80 tubes in the driver slot and cayin has personally said the amp can handle the power. Would it work with our HA6A amp? @zach915m can you plz comment on this? Have you tried any other tubes besides 12au7?


Great to hear that the adapter solution works for you.

Sounds like this is the right tube amp for me. Will join this club soon !


----------



## jandrese

iamdman said:


> Hello,
> 
> I have been looking for a tube amplifier for my HD800s and ZMF VC for quite some time. I am inching towards Cayin HA-6A and my rig is Roon Nucleus > MScaler > TT2. Will HA6 be a good option or is there any other tube amp I must also be considering in that price range? I like the Amp out of TT2 as it is and so dont want to get any SS amp and have tube. I am not much into tube rolling etc and I would likely stick to the stock tubes - I think!
> 
> ...


I love the HA-6A with my VC. The stock tubes are very good sounding. Tube rolling can change the sound signature within certain parameters but it’s not necessary.


----------



## ThanatosVI

jandrese said:


> I love the HA-6A with my VC. The stock tubes are very good sounding. Tube rolling can change the sound signature within certain parameters but it’s not necessary.


Maybe not necessary, but it's so much fun!


----------



## jandrese

ThanatosVI said:


> Maybe not necessary, but it's so much fun!


Right on. Currently, I’m running KT88 power tubes and the Baldwin drivers that ZMF included in the package. So far I’ve found that it’s best when the tubes compliment each other. For example, the stock EL34 are richer in the midrange than the KT88 and benefit from the more linear, cleaner stock 12AU7 driver tubes. The opposite is true of the Gold Lion KT88/Baldwin 12AU7 combo. The KT88 with the stock drivers was too much of the same thing and especially so in ultralinear mode. I might prefer the current setup sonically, but one or both of these tubes, the Baldwins I think, are a bit noisy in that they seem a bit microphonic and they tinkle quite a bit when warming up and cooling off and sometimes for no apparent reason. 

Tonight I’m listening to Pink Floyd through the ZMF Atrium headphones with the amp in triode mode and it’s wonderful. Am I really planning on selling these headphones?


----------



## shafat777

Got some bad news guys, I think my HA6A just crapped out on me. It was working fine, then all of a sudden, the sound cut off. Tubes light up, but no sound from either of the outputs. I have swapped out the tubes, tried two seperate dacs, tried both inputs, still no sound. Can someone plz help me? I bought it from ZMF, should i contact zach or cayin? Any help would be appreciated.


----------



## lightoflight (Nov 10, 2022)

shafat777 said:


> Got some bad news guys, I think my HA6A just crapped out on me. It was working fine, then all of a sudden, the sound cut off. Tubes light up, but no sound from either of the outputs. I have swapped out the tubes, tried two seperate dacs, tried both inputs, still no sound. Can someone plz help me? I bought it from ZMF, should i contact zach or cayin? Any help would be appreciated.


It sounds like your high voltage fuse burned out. Try replacing it.


----------



## shafat777

lightoflight said:


> It sounds like your high voltage fuse burned out.


What should i do? I think the amp came with extra fuse but im not sure if those are what burnt out. How do i swap it?


----------



## lightoflight

shafat777 said:


> What should i do? I think the amp came with extra fuse but im not sure if those are what burnt out. How do i swap it?


Turn the fuse holder counterclockwise with a flathead screwdriver till it releases. It's the round plastic holder next to the AC power input.


----------



## jonathan c

It couldn’t be the fuse being blown - why would the tubes still light up?


----------



## shafat777

@lightoflight
Okay that did the trick. Wow you sir are a savior. Thank you so much. Care to elaborate how you figured this out? Also, why did it happen? Is it common for a fuse to blow on an amp less than 2 weeks old? I would really like to know.

Thank you for your time.


----------



## lightoflight

jonathan c said:


> It couldn’t be the fuse being blown - why would the tubes still light up?


I don't know. If I remember correctly, when the HV fuse is blown, the tubes still light up but does not heat up and there's no signal when turning up the volume dial.


----------



## lightoflight

shafat777 said:


> @lightoflight
> Okay that did the trick. Wow you sir are a savior. Thank you so much. Care to elaborate how you figured this out? Also, why did it happen? Is it common for a fuse to blow on an amp less than 2 weeks old? I would really like to know.
> 
> Thank you for your time.


It happened to me once and I freaked out just like you did.  😂

I knew to check the fuse because I've read about this situation in the previous pages of this thread.


----------



## shafat777

After the recent incident with the fuse blowing out, i have decided to stockpile some fuses for the future. Seems these fuses are readily available in hardware stores as well as Amazon.


----------



## lightoflight (Nov 14, 2022)

What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.

The blue glow is awesome, isn't it?


----------



## shafat777

lightoflight said:


> What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.
> 
> They glow awesome, don't they?


Mad respect for utilizing some much needed socket savers. For some reason, the stock sockets with this amps seems kinda loose to me, IMO. And since i just got this amp, chances are i ll be swapping tubes for a while to dial in the sound and socket savers are a must have for that purpose. 

Speaking of Power tubes, I think im gonna stick to KT88s for now. Beeing swapping between PSVANE KT88 T2 and Gold Lions at the moment and am preferring the gold lions over the psvane. Once I get a bit more lsitening time with those, i might splash some cash for Sophia Electric Coke Bottle KT88s. I really like how your amp turned out with the tung sols.


----------



## ThanatosVI

lightoflight said:


> What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.
> 
> The blue glow is awesome, isn't it?





shafat777 said:


> Mad respect for utilizing some much needed socket savers. For some reason, the stock sockets with this amps seems kinda loose to me, IMO. And since i just got this amp, chances are i ll be swapping tubes for a while to dial in the sound and socket savers are a must have for that purpose.
> 
> Speaking of Power tubes, I think im gonna stick to KT88s for now. Beeing swapping between PSVANE KT88 T2 and Gold Lions at the moment and am preferring the gold lions over the psvane. Once I get a bit more lsitening time with those, i might splash some cash for Sophia Electric Coke Bottle KT88s. I really like how your amp turned out with the tung sols.


My favourite KT88 tubes are the mentioned Sophia Electric KT88s.
On top of sounding nice they also look really nice with the blue glass and unique shape


----------



## jandrese

lightoflight said:


> What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.
> 
> The blue glow is awesome, isn't it?


Man, love the blue glow. I spent some time with Gold Lion KT88 and enjoyed it. Back to the stock EL-34 tubes, which I might prefer.


----------



## krude

lightoflight said:


> What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.
> 
> The blue glow is awesome, isn't it?


How's the bass on them? Im looking for a warm power tube with strong bass for Susvara. At the moment settled for RCA Black Plate 12AU7 into Gold Lion KT88 ... need some socket savers 😂


----------



## Newbman123

krude said:


> How's the bass on them? Im looking for a warm power tube with strong bass for Susvara. At the moment settled for RCA Black Plate 12AU7 into Gold Lion KT88 ... need some socket savers 😂


What made you go for the black plate over the clear tops?


----------



## krude

Newbman123 said:


> What made you go for the black plate over the clear tops?


I was after warm but still detailed sound and black plate was one of the top recommendations. I also have vintage Sylvanias that are great but Black Plates are warmer to my ear.


----------



## lightoflight

krude said:


> How's the bass on them? Im looking for a warm power tube with strong bass for Susvara. At the moment settled for RCA Black Plate 12AU7 into Gold Lion KT88 ... need some socket savers 😂


I originally preferred the Gold Lion KT77. Now, I feel they have too much bass and sometimes depending on my mood, a tad too bright. The 7581A has less amount of bass, so you might want to look into the GL KT77.


----------



## busseysound

lightoflight said:


> What is everyone's favorite power tubes so far? I've narrowed it down to these Tung-Sol 7581A as my preference, they are not as bright as the KT88 and not overly lush like the EL34.
> 
> The blue glow is awesome, isn't it?


I really like the Tesla Vrsovice KT88's


----------



## shafat777

krude said:


> I was after warm but still detailed sound and black plate was one of the top recommendations. I also have vintage Sylvanias that are great but Black Plates are warmer to my ear.


I also settled with RCA Black plate 12au7s. I also have tried GE pewter plates and found them to be really airy with tons on top end sparkle.  If youre looking for really warm sounding tubes (not necessarily bassy) then I would strongly recommend Amperex orange globe 12au7s. These were my first ever tubes that i rolled on the HA6A and It gave me a lot of low end warmth with decent amount of mid bass and smooth treble with deep vocals.


----------



## shafat777

Anyone else is having any 160ma 250V High voltage fuses blow issue in their amp? I blew both of my spare ones the last 2 days and I literally dont know what to do? First fuse blew while i was listening to the music, while the 2nd one blew last night when the amp wasnt in use. I would to get some help regarding this matter. 

Thank you.


----------



## krude

shafat777 said:


> Anyone else is having any 160ma 250V High voltage fuses blow issue in their amp? I blew both of my spare ones the last 2 days and I literally dont know what to do? First fuse blew while i was listening to the music, while the 2nd one blew last night when the amp wasnt in use. I would to get some help regarding this matter.
> 
> Thank you.


The fuse on the inside of the amp blew up on me this summer while tube rolling. Nothing else so far 🤔


----------



## shafat777

krude said:


> The fuse on the inside of the amp blew up on me this summer while tube rolling. Nothing else so far 🤔


oh i see. I have been tube rolling a lot as well but i was under the impression my tubes were all good, since i use the exact same tubes in my Elise OTL. Can you plz tell me which tubes you were rolling? Power tubes? Do you use any socket savers? Any info would be helpful. Thank you


----------



## krude

shafat777 said:


> oh i see. I have been tube rolling a lot as well but i was under the impression my tubes were all good, since i use the exact same tubes in my Elise OTL. Can you plz tell me which tubes you were rolling? Power tubes? Do you use any socket savers? Any info would be helpful. Thank you


I was rolling power tubes I think. No socket savers. It also blew up after I finished my session and only noticed when I tried to power the amp on the next day which threw me off.


----------



## shafat777

krude said:


> I was rolling power tubes I think. No socket savers. It also blew up after I finished my session and only noticed when I tried to power the amp on the next day which threw me off.


Okay thanks. I think that could have also been the issue with my unit, imo. I have only used psvane kt88 tubes since I got the amp and have only recently swapped those out for some gold lion kt88 and both times when the fuses blew, the kt88 we being used. But the same gold lion tubes work flawless in my elise otl amp. I'm not sure if those gold lions are the culprit. Now I have gone throw all three of the fuses, I am waiting for spare ones to arrive via Amazon. Can you think of anything else that can cause this issue?


----------



## lightoflight

My fuse blew once when I first got my GL KT88. I hardly use the GL KT88, maybe three or four times since and it hasn't blown a fuse yet. I roll tubes everyday with socket savers.


----------



## krude

shafat777 said:


> Okay thanks. I think that could have also been the issue with my unit, imo. I have only used psvane kt88 tubes since I got the amp and have only recently swapped those out for some gold lion kt88 and both times when the fuses blew, the kt88 we being used. But the same gold lion tubes work flawless in my elise otl amp. I'm not sure if those gold lions are the culprit. Now I have gone throw all three of the fuses, I am waiting for spare ones to arrive via Amazon. Can you think of anything else that can cause this issue?


Hmm no idea. I use GL KT88 in mine with no issues. You have the tube select switch in the back in the correct position I assume.


----------



## shafat777

krude said:


> Hmm no idea. I use GL KT88 in mine with no issues. You have the tube select switch in the back in the correct position I assume.


Yes sir. I have the switch to kt88 on the back of the amp. I might give another set of gold lions a shot once I get the spare fuses delivered. Thank you for the suggestion. If you can think of anything else, please give me a shout.


----------



## lightoflight (Nov 21, 2022)

Hi. I just got word that the E80CC is compatible with the HA-6A.







Mine will be delivered here for listening in late December.


----------



## shafat777

lightoflight said:


> Hi. I just got word that the E80CC is compatible with the HA-6A.
> 
> 
> 
> ...


Thats not what i heard from Cayin....They finally messaged me saying that the engineers confirmed, it only supports ecc82


----------



## shafat777

Here it is. I hope you are right though. I wanna tube roll something else besides the 12au7.


----------



## lightoflight

shafat777 said:


> Here it is. I hope you are right though. I wanna tube roll something else besides the 12au7.


Your message is asking about the ECC80. I am confirming E80CC. I think the ECC80 in your message is a typo?


----------



## shafat777

lightoflight said:


> Your message is asking about the ECC80. I am confirming E80CC. I think the ECC80 in your message is a typo?


Those tubes are the same. The same applies for ECC82 vs E82CC tubes.


----------



## lightoflight

shafat777 said:


> Those tubes are the same. The same applies for ECC82 vs E82CC tubes.


I know ECC82 is the European label for the 12AU7 in America, but I don't recognize ECC80 and cannot find anything related to that on the internet in regard to pre-amp tubes.


----------



## shafat777

lightoflight said:


> I know ECC82 is the European label for the 12AU7 in America, but I don't recognize ECC80 and cannot find anything related to that on the internet in regard to pre-amp tubes.


I hope you re correct and our amp can actually handle the extra power from these tubes. I would like you to be the first one to try though lol. Please keep us posted


----------



## joseG86

So the E80CC is not compatible with HA-6A??


----------



## shafat777

joseG86 said:


> So the E80CC is not compatible with HA-6A??


We are still not sure yet. @lightoflight got confirmation saying that those tubes are supported, while i got a mesage from Cayin Support suggesting that they are not.


----------



## AudioPowerHead (Nov 25, 2022)

Joined the club today. New black unit with orange glow of the VU meters.
Can't wait to have it burned in and start doing some tube rolling. Big rabbit hole but fun times ahead !

Special thanks to @project86 for his great write-up in darko.audio and also the great YT videos from @Relaxasaurus (aka MidFi Guy) on this HA-6A. Had enjoyed reading and watching them before finally deciding to get this model.


----------



## Mattyjm

AudioPowerHead said:


> Joined the club today. New black unit with orange glow of the VU meters.
> Can't wait to have it burned in and start doing some tube rolling. Big rabbit hole but fun times ahead !
> 
> Special thanks to @project86 for his great write-up in darko.audio and also the great YT videos from @Relaxasaurus (aka MidFi Guy) on this HA-6A. Had enjoyed reading and watching them before finally deciding to get this model.


Cayin now has the ha-6a in black?? When was this a thing?


----------



## AudioPowerHead

Mattyjm said:


> Cayin now has the ha-6a in black?? When was this a thing?


Apparently Cayin just started shipping these black units in mid Nov.


----------



## joseG86

AudioPowerHead said:


> Joined the club today. New black unit with orange glow of the VU meters.
> Can't wait to have it burned in and start doing some tube rolling. Big rabbit hole but fun times ahead !
> 
> Special thanks to @project86 for his great write-up in darko.audio and also the great YT videos from @Relaxasaurus (aka MidFi Guy) on this HA-6A. Had enjoyed reading and watching them before finally deciding to get this model.


Congrats on the unit, looks beautiful, exactly the same but in black right?


----------



## AudioPowerHead

joseG86 said:


> Congrats on the unit, looks beautiful, exactly the same but in black right?


Thanks. Yes everything the same as silver except in black color.
I really like the orange glow of the VU meters vs its siblings that has it in white.


----------



## joseG86

AudioPowerHead said:


> Thanks. Yes everything the same as silver except in black color.
> I really like the orange glow of the VU meters vs its siblings that has it in white.


Wait until you hear the GL KT88


----------



## AudioPowerHead

joseG86 said:


> Wait until you hear the GL KT88


I know... can't wait.

My plan is to start with Mullard EL34/ Sylvania 12AU7 in Triode mode as I am into the mids. Then subsequently try the other extreme of KT88 in UL mode. Then different permutations of mix and match to dial in to the sound signature that I like. But I am likely to skew towards the EL34 camp due to my preference. Moreover, I have the Violectric V850/280 stack which gives me relatively good steady state sound already. Am looking for more of that tube magic to pair with my existig ZMF Verite and Aeolus.


----------



## shafat777

AudioPowerHead said:


> Joined the club today. New black unit with orange glow of the VU meters.
> Can't wait to have it burned in and start doing some tube rolling. Big rabbit hole but fun times ahead !
> 
> Special thanks to @project86 for his great write-up in darko.audio and also the great YT videos from @Relaxasaurus (aka MidFi Guy) on this HA-6A. Had enjoyed reading and watching them before finally deciding to get this model.


Congrats on the new unit. Its a fantastic amp when paired with good tubes. You have some really fun days ahead of you with plenty of options to tube roll. Gold LIon kt88 is a great place to start. Also there are an abundance of 12au7 tube options to really dial in the sound. Happy listening !


----------



## AudioPowerHead

shafat777 said:


> Congrats on the new unit. Its a fantastic amp when paired with good tubes. You have some really fun days ahead of you with plenty of options to tube roll. Gold LIon kt88 is a great place to start. Also there are an abundance of 12au7 tube options to really dial in the sound. Happy listening !


Thanks. For sure will try GLKT88 since both you and joseG86 has recommended me.  Just taking it slow for now 

Curious. Has anyone tried the Sophia Electric 12AU7, KT88 or EL34 tubes ? They are expensive but are they worth the money ?


----------



## ThanatosVI

AudioPowerHead said:


> Thanks. For sure will try GLKT88 since both you and joseG86 has recommended me.  Just taking it slow for now
> 
> Curious. Has anyone tried the Sophia Electric 12AU7, KT88 or EL34 tubes ? They are expensive but are they worth the money ?


Congratz on the Black Ha-6a.
Personally I prefer the White VU Meters from the siblings but it still looks better than the original Silver/blue variant.

I use Sophia Electric KT88 and 12au7 in my Octave V16. Gorgeous tubes and I can recommend them.

Very detailed and spacious presentation. Great extension on both ends and some nice warmth in the midrange.


----------



## shafat777

AudioPowerHead said:


> Thanks. For sure will try GLKT88 since both you and joseG86 has recommended me.  Just taking it slow for now
> 
> Curious. Has anyone tried the Sophia Electric 12AU7, KT88 or EL34 tubes ? They are expensive but are they worth the money ?


Haha I'm glad you mentioned it as I am waiting for my delivery of Sophia electric kt88 coke bottle at the moment. So far, I have tried two different sets of kt88 power tube with my amp. First set was gold lion kt88 and the current one I am using is psvane kt88 t2 gray bottles. Both tubes are a step up from my stock el34 electro harmonix tubes. The gold lions are dynamic, punchy with crisp mids and extended highs, where as the psvane are warm, thick and very tubey sound with enhanced mids and vocal. Hopefully the Sophia electric tubes sits somewhere in between. For $400 a pair, I hope these will end for me the search for power tube on this amp


----------



## AudioPowerHead

ThanatosVI said:


> Congratz on the Black Ha-6a.
> Personally I prefer the White VU Meters from the siblings but it still looks better than the original Silver/blue variant.
> 
> I use Sophia Electric KT88 and 12au7 in my Octave V16. Gorgeous tubes and I can recommend them.
> ...


Thanks. Appreciate the feedback and reco on SE tubes. Will progressively move up to them once I have clarity on which side (EL34 or KT88)  I'm leaning towards.


----------



## AudioPowerHead

shafat777 said:


> Haha I'm glad you mentioned it as I am waiting for my delivery of Sophia electric kt88 coke bottle at the moment. So far, I have tried two different sets of kt88 power tube with my amp. First set was gold lion kt88 and the current one I am using is psvane kt88 t2 gray bottles. Both tubes are a step up from my stock el34 electro harmonix tubes. The gold lions are dynamic, punchy with crisp mids and extended highs, where as the psvane are warm, thick and very tubey sound with enhanced mids and vocal. Hopefully the Sophia electric tubes sits somewhere in between. For $400 a pair, I hope these will end for me the search for power tube on this amp


<smile>
On tube rolling, can't wait to join you guys at the summit (Mt Everest ?). Am still at base camp only. But I will take it slow and enjoy the journey of climbing (discovery).


----------



## shafat777

Stay tuned


----------



## shafat777

Sophia ❤️


----------



## ThanatosVI

shafat777 said:


> Sophia ❤️


I love that Coke bottle glass compared to regular KT88 tubes


----------



## joseG86

ThanatosVI said:


> I love that Coke bottle glass compared to regular KT88 tubes





shafat777 said:


> Sophia ❤️


I wonder if they sound like GL but more detailed while keeping the amount of great bass (@ThanatosVI)


----------



## ThanatosVI

joseG86 said:


> I wonder if they sound like GL but with more detailed while keeping the amount of great bass


They keep the bass, sound more spacious and detailed but slightly less warm

(From memory,  won't be able to A/B them again until mid Dezember)


----------



## shafat777

ThanatosVI said:


> I love that Coke bottle glass compared to regular KT88 tubes


Couldnt agree more brother. Ever since you mentioned a few pages earlier that youre running a set of these, i ve been itching to get a set myself. Finally pulled the trigger and to my surprise, these arrived rather quikc (3 business days). Out of the box, these sound open, wide, with tons and tons of clean detail. Bass extension/separation is by far the best ive heard from a kt88, period. The low end is extremely tight, with each low note distinguishable from one another while maintaining weight/slam individually. These tubes are finally letting my smooth plate Telefunken drivers do their magic. The PSvane power these replaced were too tubey and mellowed out too much of the vocals and upper mids. 

But i really didnt care any of these characteristics. I ordered them because they look beautiful and i knew they would rock in my Ha6A. They sound good too as it turns out....


----------



## shafat777 (Nov 25, 2022)

joseG86 said:


> I wonder if they sound like GL but more detailed while keeping the amount of great bass (@ThanatosVI)


The Sophia kt88 sounds more like the Gold Lion 88 than the PSVane 88. Just from the first few hours of listening, i can say these are a more refined, textured version of Gold Lion with/ Blue Coke bottles lol.


----------



## Michaels1963

Cayin HA-6A Black is in stock and on Black Friday Sale Price at Music Teck the USA distributor (I just ordered mine)
https://shop.musicteck.com/products...es-headphone-amplifier?variant=43693316047138


----------



## shafat777

I have set of 4 (2 coin base, 2 fat/thick base) GE 22de4 tubes that i can sell to anyone interested......


----------



## Michaels1963

shafat777 said:


> I have set of 4 (2 coin base, 2 fat/thick base) GE 22de4 tubes that i can sell to anyone interested......


----------



## Michaels1963

Do the GE rectifier tubes make a difference over the stock RCA's ?


----------



## shafat777

Michaels1963 said:


> Do the GE rectifier tubes make a difference over the stock RCA's ?


To me, the Ge sounds a little more dynamic and not as warm as the stock RCA. However, the sound seems wider with the stock RCA. I originally bought these as a backup to my stock rcas because these were hard to find. I just scored a set of Sylvania 22de4s so i m gonna let my GEs go for a fraction of what i had to pay to collect all 4. I posted here because i want my fellow cayin amp owners to get first dibs before i post it on classified.


----------



## UntilThen

AudioPowerHead said:


> Curious. Has anyone tried the Sophia Electric 12AU7, KT88 or EL34 tubes ? They are expensive but are they worth the money ?



Go NOS. Good KT88 and EL34 tubes are like diamonds.


----------



## Michaels1963

shafat777 said:


> I have set of 4 (2 coin base, 2 fat/thick base) GE 22de4 tubes that i can sell to anyone interested......
> 
> 
> 
> To me, the Ge sounds a little more dynamic and not as warm as the stock RCA. However, the sound seems wider with the stock RCA. I originally bought these as a backup to my stock rcas because these were hard to find. I just scored a set of Sylvania 22de4s so i m gonna let my GEs go for a fraction of what i had to pay to collect all 4. I posted here because i want my fellow cayin amp owners to get first dibs before i post it on classified.


----------



## Michaels1963

what's your asking price? for two coin base or tall base on only need two


----------



## shafat777

Michaels1963 said:


> what's your asking price? for two coin base or tall base on only need two


Pm'ed


----------



## AudioPowerHead

No hiss. No hum. All the initial reservations about noise floor totally unfounded. Pure sonic bliss with the black ha-6a so far.

Initially used 1/4” SE output, then switched to xlr output. The staging and layering improved; likely attributed to the well balanced output transformers. Very synergistic pairing with my ZMF Verite.

Had tried KT88, found it too similar to my solid state amp Violectric V280. Am leaning more towards the el34 on TR mode for vocals/jazz at this point. For rock/electronic tracks, the UL mode is simply great. Contemplating whether I should give the GL KT77 a go as a next step to have more extensions on both high and low FR spectrums.

Just replaced the stock tubes with reissued Mullard el34/12AU7. Liking very much what I hear, smooth, warm and visceral mids that is so intoxicating. 

Wonderful amp. Thumbs up !


----------



## shafat777

AudioPowerHead said:


> No hiss. No hum. All the initial reservations about noise floor totally unfounded. Pure sonic bliss with the black ha-6a so far.
> 
> Initially used 1/4” SE output, then switched to xlr output. The staging and layering improved; likely attributed to the well balanced output transformers. Very synergistic pairing with my ZMF Verite.
> 
> ...


Glad you are enjoying this wonderful amp. I am having a blast myself. Took almost three weeks, but the amp is finally quiet/silent. Replaced the stock power tubes with Sophia Electric KT-88 coke bottle tubes and the drivers are replaced with 60s Telefunken Smooth plates 12au7. I did initially mess with the 22de4 rectifier tubes, temporarily replaced the RCA 22de4 with GE ones but that caused my high voltage fuse to pop. SO i m gonna leave those alone for now as the stock RCA 22de4 sounds amazing and doesn't necessarily change the sound for me. I am slowly getting used to the KT88 sound, even though I use kt88 tubes in my Elise OTL. Once i get feel for the sound, i m gonna give EL34 tubes a shot. You seem to prefer it over kt88 so it gives me hope that I might like it too. Thanks for your impression, I might snag a pair of cheap NOS el34 tubes and gibe those a try on a lazy Sunday.

Happy Listening


----------



## Michaels1963

shafat777 said:


> Glad you are enjoying this wonderful amp. I am having a blast myself. Took almost three weeks, but the amp is finally quiet/silent. Replaced the stock power tubes with Sophia Electric KT-88 coke bottle tubes and the drivers are replaced with 60s Telefunken Smooth plates 12au7. I did initially mess with the 22de4 rectifier tubes, temporarily replaced the RCA 22de4 with GE ones but that caused my high voltage fuse to pop. SO i m gonna leave those alone for now as the stock RCA 22de4 sounds amazing and doesn't necessarily change the sound for me. I am slowly getting used to the KT88 sound, even though I use kt88 tubes in my Elise OTL. Once i get feel for the sound, i m gonna give EL34 tubes a shot. You seem to prefer it over kt88 so it gives me hope that I might like it too. Thanks for your impression, I might snag a pair of cheap NOS el34 tubes and gibe those a try on a lazy Sunday.
> 
> Happy Listening


If the GE 22DE4 Rectifier tubes blow high voltage fuses, why didn't you tell me Now that you Sold me 2ea I don't want any problems with fuses Thanks


----------



## shafat777

Michaels1963 said:


> If the GE 22DE4 Rectifier tubes blow high voltage fuses, why didn't you tell me Now that you Sold me 2ea I don't want any problems with fuses Thanks


Whoah, just relax. The individual tube that caused me issue is not the tube that you bought from me. I still have it. It was fat base Ge tube bought as part of a lot of 27 tubes from ebay. What you bought is coin base GE tubes that many members around here and the HA300 forum use. If you dont want to, please pm me and I will issue a full refund, no question asked. I would not like to discuss sale related conversation here in this forum. PM me if you have any concerns or questions.


----------



## Michaels1963

I'm nice and relaxed we're good...  it's just nice to know the issue thanks for the clarification about the different GE tubes


----------



## lightoflight

AudioPowerHead said:


> Contemplating whether I should give the GL KT77 a go as a next step to have more extensions on both high and low FR spectrums.


The GL KT77 will do the trick. JJ KT77 is not bad, it's just a little softer than the GL. Also, I recommend replacing the JJ 12AU7 if you haven't already done it, they are quite dull.


----------



## AudioPowerHead

lightoflight said:


> The GL KT77 will do the trick. JJ KT77 is not bad, it's just a little softer than the GL. Also, I recommend replacing the JJ 12AU7 if you haven't already done it, they are quite dull.


Thanks for the tip on KT77. Am thinking whether purchase of it (GL or JJ) will be a waste of money if the UL mode can already emulate the extended treble and bass.

Am currently using Mullard 12AU7. Plan to rotate this with my NOS Sylvania interchangeably. No going back to stock tubes for sure.


----------



## krude (Dec 1, 2022)

For those interested I have a pair of GL 12AU7, Black Treasure KT88-Z and Black Treasure 6CA7-Z (EL34) if anyone is interested.

On the subject of GL KT77 I use it for the least few days and I really enjoy it. In my system (with RCA black plate 12AU7) it has a rounded vintage presentation with a lot of bass and mid bloom, which is what I was going for recently. It's an acquired taste for sure but I wanted a bit of that retro bombastic flavour with good bass and dynamics.


----------



## Newbman123

krude said:


> For those interested I have a pair of GL 12AU7, Black Treasure KT88-Z and Black Treasure 6CA7-Z (EL34) if anyone is interested.
> 
> On the subject of GL KT77 I use it for the least few days and I really enjoy it. In my system (with RCA black plate 12AU7) it has a rounded vintage resentation with a lot of bass and mid bloom, which is what I was going for recently. It's an acquired taste for sure but I wanted a bit of that retro bombastic flavour with good bass and dynamics.


So the sophia electric kt88 is better than both the gl and black treasure kt88?


----------



## AudioPowerHead

shafat777 said:


> Glad you are enjoying this wonderful amp. I am having a blast myself. Took almost three weeks, but the amp is finally quiet/silent. Replaced the stock power tubes with Sophia Electric KT-88 coke bottle tubes and the drivers are replaced with 60s Telefunken Smooth plates 12au7. I did initially mess with the 22de4 rectifier tubes, temporarily replaced the RCA 22de4 with GE ones but that caused my high voltage fuse to pop. SO i m gonna leave those alone for now as the stock RCA 22de4 sounds amazing and doesn't necessarily change the sound for me. I am slowly getting used to the KT88 sound, even though I use kt88 tubes in my Elise OTL. Once i get feel for the sound, i m gonna give EL34 tubes a shot. You seem to prefer it over kt88 so it gives me hope that I might like it too. Thanks for your impression, I might snag a pair of cheap NOS el34 tubes and gibe those a try on a lazy Sunday.
> 
> Happy Listening


Depends on your preference on music genre, you’ll either hate or love the el34 as it is mids focused. For me, I have been listening to SS amps for years  (Vio V280). And what I am after is the seductive, velvet-smooth mids that only tube amps can provide. And in particular, either 300b or el34 amps. However, upkeeping a 300b amp requires expensive tubes replacement (elriogs etc) and therefore I have decided to get a el34 amp instead. The ha-6a checked that box for me while giving me additional kt88 tube(and its variants) option. Although I must admit, I would rather use my V280 if I want to listen to kt88 or the SS sound signature.

Not planning to mess around too much with the 22de4s as well. Think the impact to sound is more pronounced for power and pre-amp driver tubes. Based on my limited understanding, RCA 22de4 provide good top end air and stage relative to others like GE/Sylvania. With the current short supply and price inflation of these tubes, I don’t plan to spend too much time and money on rectifiers.

On NOS tubes, the prices are just crazy. Instead, I might buy the SE el34 at a later stage when I have the amp fully burned in and gotten well acquainted with Millard’s sound signature.


----------



## AudioPowerHead

krude said:


> For those interested I have a pair of GL 12AU7, Black Treasure KT88-Z and Black Treasure 6CA7-Z (EL34) if anyone is interested.
> 
> On the subject of GL KT77 I use it for the least few days and I really enjoy it. In my system (with RCA black plate 12AU7) it has a rounded vintage presentation with a lot of bass and mid bloom, which is what I was going for recently. It's an acquired taste for sure but I wanted a bit of that retro bombastic flavour with good bass and dynamics.


Do you find similarities between el34 on UL mode vs KT77 on TR mode ?


----------



## krude

AudioPowerHead said:


> Do you find similarities between el34 on UL mode vs KT77 on TR mode ?


KT77 is a variation on EL34, did you mean KT77 in UL to KT88 in triode? KT77 in UL is still a lot more "tuby" than KT88 in triode. KT88 is almost like a SS amp (they have their own characteristics ofc) and GL KT77 is like an old vintage tube amp. I tried Electroharmonix EL34 as well, and from memory it was very clean and a bit soft, so again, different. Different brands have different house sound.


----------



## AudioPowerHead

krude said:


> KT77 is a variation on EL34, did you mean KT77 in UL to KT88 in triode? KT77 in UL is still a lot more "tuby" than KT88 in triode. KT88 is almost like a SS amp (they have their own characteristics ofc) and GL KT77 is like an old vintage tube amp. I tried Electroharmonix EL34 as well, and from memory it was very clean and a bit soft, so again, different. Different brands have different house sound.


Thanks for sharing. Am not going for KT88 for the SS sound (already have SS amp). Am wondering if I should just stick to el34 and then TR for jazz, vocals, pianos and then UL for rock, electronic trance etc. I have yet to hear KT77 but suspect the nuance may not be big vs el34( if I have it in UL mode).


----------



## krude

AudioPowerHead said:


> Thanks for sharing. Am not going for KT88 for the SS sound (already have SS amp). Am wondering if I should just stick to el34 and then TR for jazz, vocals, pianos and then UL for rock, electronic trance etc. I have yet to hear KT77 but suspect the nuance may not be big vs el34( if I have it in UL mode).


Each EL34 (and variants like KT77 and 6ca7) will be different. I would recommend getting a few brands and playing around with it. Also 12au7 tubes. 

Just google for your preference (bright, warm, airy, sweet etc), find some recommendations and roll some tubes


----------



## krude

lightoflight said:


> I originally preferred the Gold Lion KT77. Now, I feel they have too much bass and sometimes depending on my mood, a tad too bright. The 7581A has less amount of bass, so you might want to look into the GL KT77.


That recommendation changed my view of the HA6a in the past few days. I had a set of GL KT77 stashed in a box already (I buy a few sets of tubes usually in one go) but never gave them a proper chance to settle I think. Combined with the RCA Black Plates these are bombastically vintage with a nice rounded bass hump. Me likey : )


----------



## lightoflight

Hi all,
I was wondering if there's a product registration card that came with your unit. I just can't seem to find it anywhere or it didn't come with one.


----------



## Michaels1963

lightoflight said:


> Hi all,
> 
> I was wondering if there's a product registration card that came with your unit. I just can't seem to find it anywhere or it didn't come with one.





lightoflight said:


> My brand new unit that was delivered last week didn't come with a registration card


----------



## lightoflight

@Michaels1963 Thanks for checking.


----------



## Michaels1963

lightoflight said:


> Hi all,
> I was wondering if there's a product registration card that came with your unit. I just can't seem to find it anywhere or it didn't come with one.


Just checked with the USA Distributor Musicteck.com there is no registration card You go back to the place of purchase for service and they have your sales record on file.
https://shop.musicteck.com/products...es-headphone-amplifier?variant=43693316047138


----------



## lightoflight

Michaels1963 said:


> Just checked with the USA Distributor Musicteck.com there is no registration card You go back to the place of purchase for service and they have your sales record on file.
> https://shop.musicteck.com/products...es-headphone-amplifier?variant=43693316047138


Right on, thanks. 👍


----------



## shafat777

Rolled a set of NOS Sylvania 22DE4 rectifiers in my HA6A. I have only used the stock RCA except for 2 hours when I tried some GE 22DE4s a shot. So far, the Sylvanias show great low end extension with tight, impactful bass. The RCA however has a wider soundstage with great imaging. Gonna give these some chances to burn in along with my Sophia Electric KT88-ST power tubes and Telefunken Smooth plate drivers. Overall I am really happy with this amp right now (had some quirks to take care of at the beginning).


----------



## Michaels1963 (Dec 5, 2022)

Do Socket Savers actually work, or do they get pulled out when you try to remove a tube?


----------



## AudioPowerHead

Michaels1963 said:


> Do Socket Savers actually work, or do they get pulled out when you remove a tube?


Think they should work. The only problem seems the increased height might prevent the cage from used.


----------



## AudioPowerHead

shafat777 said:


> Rolled a set of NOS Sylvania 22DE4 rectifiers in my HA6A. I have only used the stock RCA except for 2 hours when I tried some GE 22DE4s a shot. So far, the Sylvanias show great low end extension with tight, impactful bass. The RCA however has a wider soundstage with great imaging. Gonna give these some chances to burn in along with my Sophia Electric KT88-ST power tubes and Telefunken Smooth plate drivers. Overall I am really happy with this amp right now (had some quirks to take care of at the beginning).


Great to hear you are enjoying this amp. So am I. At this point, I am still in process of dialing in to the sound that I might like. 

Tried a pair of nos Sylvania 12au7, there was increased clarity and resolution but lost the warmth and richness of sound as compared to reissued Mullards. Currently settled on using reissued Mullard for both el34 and 12au7, this  seems to be the combo I like vs stock tubes and the nos Sylvania. 

Next stop, SE el34. Hope that will somewhat increase the details, stage and bass while keeping the warmth, smoothness and richness of Millard 12au7 at same time. Well I shall see(hear) when it arrives. 

This tube amp rabbit hole can indeed be big and deep. But one that I am willing to continue digging(for now). Happy listening !


----------



## Michaels1963 (Dec 6, 2022)

I'm rolling an interesting tube today KT99 (KT90) Found these in my high end closet there out of a 1980s Audio Research M 300 triod mono block Audio research gives them a multi label KT99, KT90 and 6550 with 1950s Sylvania NOS stock 12Au7


----------



## krude

Michaels1963 said:


> I'm rolling an interesting tube today KT99 (KT90) Found these in my high end closet there out of a 1980s Audio Research M 300 triod mono block Audio research gives them a multi label KT99, KT90 and 6550 with 1950s Sylvania NOS stock 12Au7


Do tell us how it goes


----------



## Michaels1963

krude said:


> Do tell us how it goes


Will do after a few days


----------



## Michaels1963

krude said:


> Do tell us how it goes


----------



## jamato8

This tube amp seems to offer a lot of fun tube rolling opportunities.


----------



## jamato8

Michaels1963 said:


> Do Socket Savers actually work, or do they get pulled out when you try to remove a tube?


Why use them. They add more connections between the tube and the circuit and questionable connections (what is made of) in the socket saver. Socket savers are really made for something where tubes are being changed constantly, like a tube testers. I have many socket savers but wouldn't use them in an amp as I see no reason. And if the sockets go out that easy on an amp, they were too good to begin with.


----------



## jamato8

krude said:


> Do tell us how it goes





Michaels1963 said:


> I'm rolling an interesting tube today KT99 (KT90) Found these in my high end closet there out of a 1980s Audio Research M 300 triod mono block Audio research gives them a multi label KT99, KT90 and 6550 with 1950s Sylvania NOS stock 12Au7


It would be fun to try some KT90s. I have the good ones from Yugoslavia before they started having issues. Also GE 6550, EL34s from the 1950s and other nice power tubes in NOS.


----------



## Michaels1963 (Dec 7, 2022)

jamato8 said:


> It would be fun to try some KT90s. I have the good ones from Yugoslavia before they started having issues. Also GE 6550, EL34s from the 1950s and other nice power tubes in NOS.


----------



## Michaels1963

Yes the KT99 (KT90) That I'm using are Gold Aero made In Yugoslavia


----------



## AudioPowerHead

Two weeks so far with my ha-6a pairing with my ZMF VO/Aeolus. Zero buyer remorse. Such a joyful experience listening and playing around with the TR and UL modes depending on the music genres. Versatility is certainly a key strength of this unit. In most cases, I have a preference for TR mode for the lush and smoother sound with the el34. Can listen for hours without any sign of fatigue.

Still using the Reissue Mullards 12au7/el34 at this point. This seems to hit the sweet spot for me (at this point) as I simply love its warm, smooth and rich sound signature. I know the reissue Mullards are actually from New Sensor reflektor factory; not the real McCoy some may say; but it is surprisingly very good ( to my ears).

Currently waiting for some new tubes (SE el34 and NOS Mullard ecc82) to arrive soon at my door.  So much anticipation and excitement in doing more tube rolling with my Cayin. The fun continues. Happy listening all !


----------



## AudioPowerHead (Dec 10, 2022)

Sophia Electric EL34 has arrived.


----------



## shafat777

AudioPowerHead said:


> Sophia Electric EL34 has arrived.


Congrats. Let us know how they sound. Theres just something about the Sophias that just looks so darn sexy.


----------



## AudioPowerHead

shafat777 said:


> Congrats. Let us know how they sound. Theres just something about the Sophias that just looks so darn sexy.


Initial sound impressions has been very positive (tubes still need burning in). The bass is tighter, slightly more slam impact. More clarity and refined while keeping the smooth richness of mids coming from the Mullard 12au7(still waiting for my NOS pair to arrive). Overall, a more airy, spacious and textured sound I would say. This moves the ha-6a one big step closer to the gorgeous mids that is synonymous with the Cayin 300B mk2 (with stock tubes) that I have heard before; IMHO.

Yes, and of course most of us bought the SE tubes partially because of its good looks without a doubt. The ST-shaped bottles simply makes it look more like a 300B than el34.


----------



## krude

I've written something in the HA300 MK2 thread, but it's probably even more applicable here for Susvara owners.

---


Alenotta said:


> At first with my Caldera I thought M was definitely the way to go. Recently I switched to H and decided I was wrong. H really opened it up for me. I emailed Zach from ZMF and he explained that H lessens the dampening factor. So now I’m pretty exclusively in H. I wonder if you’re experiencing similar results with the Susvara. The Caldera is 64ohms and Susvara is 60ohms so that is similar.


I'm on HA6a but I think it works in the same way. I went through the L->M->H journey with Susvara as well and there's a few things I've noticed.
1. Going up in impedance brings forward the mids, and highs (and most importantly activates the dynamcis) but also loosens up deep bass damping (which for me is a good thing on Susvara ... actually all of those things are good on Susvara, but ... check point 2.)
2. Weather this sounds good or not depends on burn in of the amp and tubes, tubes used (darker / warmer / bassy tubes tend to sound better), warm up of the amp, level you listen at. So there's a whole host of variables.
3. I generally think about it like this : I want more dynamics in the mids, and highs on Susvara. I want a looser more present and punchy bass with less damping. So I need to have a dark presentation on L to start with, so that adding more energy to M and H doesn't make it bright and biting on the Sus. So it's a balancing game. When I first start the amp L sounds best, after 20 min or so M sounds best, 10 min later H sounds best ... but if I had bright tubes and a bright DAC I maybe wouldn't be able to balance it out like that.

Also I've noticed that I need to give the amp a minute or so (maybe a few) to "settle" with the new settings. Sometimes it sounds harsh when I switch impedance and mellows out in a minute or two. Same with volume.

I'm on GL KT77, RCA Black Plate and stock RCA 22DE4, also works with Black Treasure KT88-Z with RCA Black Plate or GL 12AU7.


----------



## ungauged

Just got some vintage GEC kt88 and long plate square getter Mullard ecc82 at a good deal. 

Hope they offer a different sound signature from my long time setup of the Psvane KT88-Tii and Brimar.


----------



## GridIroN

Hey fellow humans,

just wondering what the Cayin fanbase's take is on the hiss with dynamic headphone products now? Reading through the thread I see people say Cayin claims to hve addressed this at the factory with new resistors, but there are posts in here as late as November 2022 saying their unit still exhibits this behavior. LIkewise there are posts saying they experience nothing. Others claiming they solved it by using an adapter, others claiming they solved it by switching the default tubes for anything else...

Looks like a wonderful amp I might one day soon pick up, but the hissing issue is a bit concerning considering the phones I'd use with this are dynamics...


----------



## Michaels1963

GridIroN said:


> Hey fellow humans,
> 
> just wondering what the Cayin fanbase's take is on the hiss with dynamic headphone products now? Reading through the thread I see people say Cayin claims to hve addressed this at the factory with new resistors, but there are posts in here as late as November 2022 saying their unit still exhibits this behavior. LIkewise there are posts saying they experience nothing. Others claiming they solved it by using an adapter, others claiming they solved it by switching the default tubes for anything else...
> 
> Looks like a wonderful amp I might one day soon pick up, but the hissing issue is a bit concerning considering the phones I'd use with this are dynamics...


Just received my unit Black 12/1/2022 no problems to report with any headphones I own Dynamic or Planer  Audeze, Meze, Grado, Sennheiser, Mr Speaker, Focal etc. I do use aftermarket tubes not stock EH due to improved sound. Good Luck and get your HA-6A today and Enjoy the Music


----------



## Michaels1963

ungauged said:


> Just got some vintage GEC kt88 and long plate square getter Mullard ecc82 at a good deal.
> 
> Hope they offer a different sound signature from my long time setup of the Psvane KT88-Tii and Brimar.


Nice looking tubes can't wait to hear how you like the NOS tubes. Looks like you are using socket savers on the ECC82 tubes?


----------



## jamato8

ungauged said:


> Just got some vintage GEC kt88 and long plate square getter Mullard ecc82 at a good deal.
> 
> Hope they offer a different sound signature from my long time setup of the Psvane KT88-Tii and Brimar.


The construction is a little different from GEC I have seen and the metal base is normally dull not shiny.


----------



## AudioPowerHead

Michaels1963 said:


> Just received my unit Black 12/1/2022 no problems to report with any headphones I own Dynamic or Planer  Audeze, Meze, Grado, Sennheiser, Mr Speaker, Focal etc. I do use aftermarket tubes not stock EH due to improved sound. Good Luck and get your HA-6A today and Enjoy the Music


Very nice. Congrats with getting the black unit. Enjoy !


----------



## lightoflight (Dec 12, 2022)

New pre-amp tubes on rotation.

Psvane 12AU7-S
Tungsram E80CC yellow



Spoiler: They sound like...



I'll tell you later, I need to burn-in the tall one.


----------



## Michaels1963

lightoflight said:


> New pre-amp tubes on rotation.
> 
> Psvane 12AU7-S
> Tungsram E80CC yellow
> ...


They look Great I hope the sound matches Enjoy the Music


----------



## ArkNerevar

lightoflight said:


> Tungsram E80CC yellow


this is a completely different tube type, does it actually work in the amp?


----------



## jamato8

ArkNerevar said:


> this is a completely different tube type, does it actually work in the amp?


It uses box plates, but it isn’t the appearance of a tube, but how it is made electrically yes, they are very close but draw more heater current.


----------



## ArkNerevar

Drawing more heater current is a big thing, that would strain the transformer and potentially lead to permanent serious damage.


----------



## shafat777

ArkNerevar said:


> this is a completely different tube type, does it actually work in the amp?


Both cayin support and @Andykong have told me to use  only 12au7 tubes/variants and nothing else for the driver tubes.


----------



## jamato8

They draw twice the heater current.


----------



## ArkNerevar

shafat777 said:


> Both cayin support and @Andykong have told me to use only 12au7 tubes/variants and nothing else for the driver tubes.


While it may be electrically compatible ive never heard of people including E80CC tubes as within the 12AU7 variant family.



jamato8 said:


> They draw twice the heater current.


Twice the heater current, now im no expert but surely we should hear it clearly from a Cayin engineer or @Andykong that this is not a bad idea that would kill our power transformers.


----------



## jamato8

ArkNerevar said:


> While it may be electrically compatible ive never heard of people including E80CC tubes as within the 12AU7 variant family.
> 
> 
> Twice the heater current, now im no expert but surely we should hear it clearly from a Cayin engineer or @Andykong that this is not a bad idea that would kill our power transformers.


I have many of them really nice tubes, but you have to know if your transformer can handle the doubling of the current draw for the filaments.


----------



## ArkNerevar

I do hear what you are saying jamato8, I mean, as a avid tube roller on my HA-6A im excited by the idea of another pre-amp tube to try but we have to remember that if you draw heater current over the transformers spec you a very seriously risking damaging it, not immediately, thats what fools people into thinking its ok, it wont blow up in your face but it will heat up over the norm and be damaged over time, best to hear it explicitly from your amp maker before doing such a thing.


----------



## jamato8 (Dec 12, 2022)

ArkNerevar said:


> I do hear what you are saying jamato8, I mean, as a avid tube roller on my HA-6A im excited by the idea of another pre-amp tube to try but we have to remember that if you draw heater current over the transformers spec you a very seriously risking damaging it, not immediately, thats what fools people into thinking its ok, it wont blow up in your face but it will heat up over the norm and be damaged over time, best to hear it explicitly from your amp maker before doing such a thing.


Of course, that is why you always, always find out from the manufacture the specs for the transformer. Also the plate voltage is lower than the 12AU7. They aren't just a plug and play and you have to know the specs of the circuit and the tubes you are using.


----------



## ArkNerevar

I am curious, whats the gain rating of the E80CC versus the 12AU7?


----------



## jamato8

ArkNerevar said:


> I am curious, whats the gain rating of the E80CC versus the 12AU7?


It’s a little bit higher, but you really don’t notice it very much


----------



## lightoflight

ArkNerevar said:


> this is a completely different tube type, does it actually work in the amp?


It should, I've confirmed it with Cayin.


----------



## lightoflight

In the past, I confirmed with Cayin about the Tung Sol 7581A too. Best looking natural glow when the lights are dim. Those socket savers look unpleasing, but I tube roll a lot. I have to say that I have a set of power tubes that would of loosen up those OEM sockets pretty bad if I didn't have the socket savers in there.


----------



## AudioPowerHead

lightoflight said:


> In the past, I confirmed with Cayin about the Tung Sol 7581A too. Best looking natural glow when the lights are dim. Those socket savers look unpleasing, but I tube roll a lot. I have to say that I have a set of power tubes that would of loosen up those OEM sockets pretty bad if I didn't have the socket savers in there.


Beautiful tubes ! It’s like mini Christmas trees  How do they sound ?

With the socket savers, how do you fit in the cage; if at all.


----------



## jamato8

AudioPowerHead said:


> Beautiful tubes ! It’s like mini Christmas trees  How do they sound ?
> 
> With the socket savers, how do you fit in the cage; if at all.


Why would you want to use a cage? Just don't lick the tubes and you will be ok. lol I have never over many, many years, ever used a cage over any of my tube equipment.


----------



## AudioPowerHead

jamato8 said:


> Why would you want to use a cage? Just don't lick the tubes and you will be ok. lol I have never over many, many years, ever used a cage over any of my tube equipment.


LOL. Good one


----------



## lightoflight

AudioPowerHead said:


> Beautiful tubes ! It’s like mini Christmas trees  How do they sound ?
> 
> With the socket savers, how do you fit in the cage; if at all.


I do not have a need to use the cage as I do not have any pets or children around.

My favorite tube is the KT66, the 7581A is like a stepbrother to the KT66 and it's the reason I wanted to try them. I am going to pull my notes on them:

_The sound signature is in between EL34 and KT77, not as smooth as the EL34 and not as bright as the KT77. It's like an uptick of fidelity from the EL34 without being edgy in the higher mid and treble range. Similar big soundstage as an EL34 and great bass weight and punch (but not to the level as the KT77's bass). Good holography when paired with the right tube like the GL 12AU7. The upper mid-range and treble seems to be rolled off, so it sounds smooth up top and less air but have a full body sound._


----------



## AudioPowerHead

lightoflight said:


> I do not have a need to use the cage as I do not have any pets or children around.
> 
> My favorite tube is the KT66, the 7581A is like a stepbrother to the KT66 and it's the reason I wanted to try them. I am going to pull my notes on them:
> 
> _The sound signature is in between EL34 and KT77, not as smooth as the EL34 and not as bright as the KT77. It's like an uptick of fidelity from the EL34 without being edgy in the higher mid and treble range. Similar big soundstage as an EL34 and great bass weight and punch (but not to the level as the KT77's bass). Good holography when paired with the right tube like the GL 12AU7. The upper mid-range and treble seems to be rolled off, so it sounds smooth up top and less air but have a full body sound._


Yes I use the cage for the reasons you mentioned.

Interesting, so the 7581A is sitting sort of in the middle of el34 and kt77. Am still learning and being open-minded about the tubes I could use with the ha-6a so your sharing is helpful. Thanks!


----------



## ungauged

jamato8 said:


> The construction is a little different from GEC I have seen and the metal base is normally dull not shiny.


I asked the same questions to the seller as they looked relatively brand new.  He showed me that there were variants to the metal base either being brushed or shiny depending on usage and manufacture date. Even showed me a quad with 2 of them being slightly shiny on the base as well. 

He is a reputable seller from Japan. And with them being so rare coupled with the astronomical prices, I took the bait.


----------



## OctavianH

ungauged said:


> He is a reputable seller from Japan. And with them being so rare coupled with the astronomical prices, I took the bait.


I do not want to interfere here but those look too good to be produced in 28th week of 1973 as stated on the glass. I never saw GEC/Genalex KT88 with shinny base and "Made in England" scratched on the glass. Even that logo has a strange shape compared with vintage GEC logos and even the rectangle seems narrower. What to say, they try a lot to look like GEC. I might be wrong, there are several variations as mentioned here or here but still, I keep my opinion that those are not original.

Here is a picture with one of my pairs:





Can you make more pictures? For example these areas?


----------



## Andykong

lightoflight said:


> It should, I've confirmed it with Cayin.



May I know the Cayin contact you discussed regarding using E80CC in HA-6A?  This goes against our recommendation directly.  I would like to clarify that ECC80 is not a direct replacement for EDD82, it can't be used in HA-6A.

In fact, I have responded to another query through PM last month and I used almost the exact wording to response to the same issue.  I hope I can get in touch with your Cayin contact and clarify his/her mistake regarding using ECC80 in HA-6A.


----------



## ungauged

OctavianH said:


> I do not want to interfere here but those look too good to be produced in 28th week of 1973 as stated on the glass. I never saw GEC/Genalex KT88 with shinny base and "Made in England" scratched on the glass. Even that logo has a strange shape compared with vintage GEC logos and even the rectangle seems narrower. What to say, they try a lot to look like GEC. I might be wrong, there are several variations as mentioned here or here but still, I keep my opinion that those are not original.
> 
> Here is a picture with one of my pairs:
> 
> ...


Thanks for the clarification. Would like any help if these are indeed fake as I will be heading back to Japan for work next month.

Hope these pics would suffice and sorry if it isn't really related to the HA-6A thread.


----------



## OctavianH

ungauged said:


> Thanks for the clarification. Would like any help if these are indeed fake as I will be heading back to Japan for work next month.


In my opinion what you have there are Psvane KT88C like here faked as GEC.


----------



## ungauged

OctavianH said:


> In my opinion what you have there are Psvane KT88C like here faked as GEC.


Thanks for the clarification and the link. It does look identical in construction. Sigh......


----------



## lightoflight

Andykong said:


> May I know the Cayin contact you discussed regarding using E80CC in HA-6A?  This goes against our recommendation directly.  I would like to clarify that ECC80 is not a direct replacement for EDD82, it can't be used in HA-6A.
> 
> In fact, I have responded to another query through PM last month and I used almost the exact wording to response to the same issue.  I hope I can get in touch with your Cayin contact and clarify his/her mistake regarding using ECC80 in HA-6A.


Hi Andy,
There was no name signed in the communication email with Cayin.


----------



## jamato8

Here are the tubes. Obviously the GEC shown above are from China:


----------



## AudioPowerHead

Despite due diligence, this looks like a case where caveat emptor principle does not apply as the seller provided false information or misrepresented the product.


----------



## jamato8

AudioPowerHead said:


> Despite due diligence, this looks like a case where caveat emptor principle does not apply as the seller provided false information or misrepresented the product.


There is always a possibility that the Japanese seller did not know that they were fake. Check the holes in the plates and the lack of side getter. Also, they did not make them with a shiny metal base. It was always dull and there are a number of other things that are wrong with the Tubes.


----------



## AudioPowerHead

jamato8 said:


> There is always a possibility that the Japanese seller did not know that they were fake. Check the holes in the plates and the lack of side getter. Also, they did not make them with a shiny metal base. It was always dull and there are a number of other things that are wrong with the Tubes.


You’re right. I believe even the Japanese seller has been fooled.


----------



## AudioPowerHead

Have a question on biasing. Is the ha-6a self-biasing or manual biasing ? Based on my reading, manual biasing is supposedly better in sound as it does not need bypass capacitors and the cathode is grounded through the bias meter. However, self-biasing is supposed to be better for tubes life span.

Right now, I am swooping tubes and just wondering if this topic matters at all for us who owns the ha-6a.

Would appreciate @Andykong or anyone who knows to kindly share. Thanks.


----------



## Michaels1963

AudioPowerHead said:


> Have a question on biasing. Is the ha-6a self-biasing or manual biasing ? Based on my reading, manual biasing is supposedly better in sound as it does not need bypass capacitors and the cathode is grounded through the bias meter. However, self-biasing is supposed to be better for tubes life span.
> 
> Right now, I am swooping tubes and just wondering if this topic matters at all for us who owns the ha-6a.
> 
> Would appreciate @Andykong or anyone who knows to kindly share. Thanks.


I was just thinking the same question. I don't find any information on the biasing of the HA-6A anywhere that I have looked I hope someone knows


----------



## Andykong

AudioPowerHead said:


> Have a question on biasing. Is the ha-6a self-biasing or manual biasing ? Based on my reading, manual biasing is supposedly better in sound as it does not need bypass capacitors and the cathode is grounded through the bias meter. However, self-biasing is supposed to be better for tubes life span.
> 
> Right now, I am swooping tubes and just wondering if this topic matters at all for us who owns the ha-6a.
> 
> Would appreciate @Andykong or anyone who knows to kindly share. Thanks.



HA-6A is auto-bias


----------



## AudioPowerHead

Andykong said:


> HA-6A is auto-bias


Cool. Thanks Andy !


----------



## Michaels1963

I tried the GE Rectifier tubes 22DE4 I don't hear any difference over the stock RCA rectifier tubes.   Do you hear any difference in rectifier tubes I find more on Ebay don't know if there worth the time


----------



## AudioPowerHead

Michaels1963 said:


> I tried the GE Rectifier tubes 22DE4 I don't hear any difference over the stock RCA rectifier tubes.   Do you hear any difference in rectifier tubes I find more on Ebay don't know if there worth the time


Not tried it yet although I believe there could be some degree of audio benefits with the right tubes installed based on what has been shared by others in Cayin threads.

I think more remarkable tonal alterations and sonic nuances could be derived from pre-amp input and power tubes.


----------



## Michaels1963

AudioPowerHead said:


> Not tried it yet although I believe there could be some degree of audio benefits with the right tubes installed based on what has been shared by others in Cayin threads.
> 
> I think more remarkable tonal alterations and sonic nuances could be derived from pre-amp input and power tubes.


I already tube roll the Pre and Power tubes thought I would try the Rectifier Tubes Now


----------



## Andykong

Andykong said:


> May I know the Cayin contact you discussed regarding using E80CC in HA-6A?  This goes against our recommendation directly.  I would like to clarify that ECC80 is not a direct replacement for EDD82, it can't be used in HA-6A.
> 
> In fact, I have responded to another query through PM last month and I used almost the exact wording to response to the same issue.  I hope I can get in touch with your Cayin contact and clarify his/her mistake regarding using ECC80 in HA-6A.



Since there are mixed responses regarding E80CC, we had a thorough discussion regarding the technical feasibility of this vacuum tube as a replacement for 12AU7 on our vacuum tube headphone amplifiers. After checking the specification in detail, Chen DeHai, our Chief Engineer confirmed that E80CC can be used in HA-6A and HA-3A.  The E80CC will draw more heater current, which might affect the long terms tear and wear of the amplifier slightly, but it is technically safe in HA-6A and HA-3A, it won't blow the amplifier or damage the transformers. 

We won't add E80CC to the recommended tube replacement table in our product manual.  In our past experience, this will introduce a misunderstanding that E80CC is a direct replacement of 12AU7 and can be used as a replacement in all other tube amplifiers (including speaker amplifiers) when they can't find any reference to E80CC in their product manual. 

Sorry for the miscommunication in the past, we hope this will clarify the situation.


----------



## shafat777

Andykong said:


> Since there are mixed responses regarding E80CC, we had a thorough discussion regarding the technical feasibility of this vacuum tube as a replacement for 12AU7 on our vacuum tube headphone amplifiers. After checking the specification in detail, Chen DeHai, our Chief Engineer confirmed that E80CC can be used in HA-6A and HA-3A.  The E80CC will draw more heater current, which might affect the long terms tear and wear of the amplifier slightly, but it is technically safe in HA-6A and HA-3A, it won't blow the amplifier or damage the transformers.
> 
> We won't add E80CC to the recommended tube replacement table in our product manual.  In our past experience, this will introduce a misunderstanding that E80CC is a direct replacement of 12AU7 and can be used as a replacement in all other tube amplifiers (including speaker amplifiers) when they can't find any reference to E80CC in their product manual.
> 
> Sorry for the miscommunication in the past, we hope this will clarify the situation.


Thank you Andy for the clarification, its really helpful to finally erase any form of doubt regarding this issue and now we can all go back to enjoying this wonderful amp.


----------



## krude

Andykong said:


> Since there are mixed responses regarding E80CC, we had a thorough discussion regarding the technical feasibility of this vacuum tube as a replacement for 12AU7 on our vacuum tube headphone amplifiers. After checking the specification in detail, Chen DeHai, our Chief Engineer confirmed that E80CC can be used in HA-6A and HA-3A.  The E80CC will draw more heater current, which might affect the long terms tear and wear of the amplifier slightly, but it is technically safe in HA-6A and HA-3A, it won't blow the amplifier or damage the transformers.
> 
> We won't add E80CC to the recommended tube replacement table in our product manual.  In our past experience, this will introduce a misunderstanding that E80CC is a direct replacement of 12AU7 and can be used as a replacement in all other tube amplifiers (including speaker amplifiers) when they can't find any reference to E80CC in their product manual.
> 
> Sorry for the miscommunication in the past, we hope this will clarify the situation.


Kudos. I really appreciate your efforts in providing support. You're doing an amazing job here.


----------



## lightoflight

The Tungsram E80CC is great with TS EL34.  Yet to try it with EH EL34 but I suspect it will be a great combination as well.


----------



## jamato8 (Dec 17, 2022)

lightoflight said:


> The Tungsram E80CC is great with TS EL34.  Yet to try it with EH EL34 but I suspect it will be a great combination as well.


I have many E80CC/ 6085 tubes. Nice in the right setup. They are supposed to be a long life tube, 10,000 hours. In some circuits (as long as the extra current draw for the heater is accounted for) they can sound very fine and others, too smooth. It really comes down to getting the operating points right, which is why even when tubes are close in electrical properties, doesn't mean they are just a plug and play. 

You used to be be able to buy them for 5 dollars each, as many people didn't know what to do with them. I have a box full of them. Tubes are great fun. Just know how to bias and set the operating points correctly.


----------



## AudioPowerHead

lightoflight said:


> The Tungsram E80CC is great with TS EL34.  Yet to try it with EH EL34 but I suspect it will be a great combination as well.


Curious to know how the Tungsram E80CC sound like ? Warm or neutral, detailed or rich ?


----------



## lightoflight (Dec 17, 2022)

AudioPowerHead said:


> Curious to know how the Tungsram E80CC sound like ? Warm or neutral, detailed or rich ?


They are like the GL 12AU7 but better. Better in resolution, timbre and stage depth. The soundstage is very big, and the high resolution improves the sonic imaging. The upper midrange and treble are softer which help with timbre but it's not as airy. It will help with tracks that have sibilance and high sharp notes, your listening session will be less fatiguing. I think they are slightly on the bright side (similar to GL 12AU7), which I like to combine it with EL34 or KT77 to enhance their lush sound signature.


----------



## AudioPowerHead

lightoflight said:


> They are like the GL 12AU7 but better. Better in resolution, timbre and stage depth. The soundstage is very big, and the high resolution improves the sonic imaging. The upper midrange and treble are softer which help with timbre but it's not as airy. It will help with tracks that have sibilance and high sharp notes, your listening session will be less fatiguing. I think they are slightly on the bright side (similar to GL 12AU7), which I like to combine it with EL34 or KT66 to enhance their lush sound signature.


Thanks for your feedback. Interesting to know its sonic traits as e80cc is now a “legit” tube to roll with recent clarifications given on its suitability for the ha-6a/3a.


----------



## ArkNerevar

@Andykong can we use the 6211 in the HA-6A? its similar to the 12AU7 but with lower max voltage ratings and higher Mu rating, thank you.


----------



## Michaels1963

Real KT99 (1980) Tubes Really sound good with Sylvania 12AU7 (1950) these tubes sound rich and full with loads of detail 
I'm Happy with this combo
I have dimed the light on the power switch and knob to be comfortable


----------



## AudioPowerHead

Michaels1963 said:


> Real KT99 (1980) Tubes Really sound good with Sylvania 12AU7 (1950) these tubes sound rich and full with loads of detail
> I'm Happy with this combo
> I have dimed the light on the power switch and knob to be comfortable


How do you actually dim the lights on the power switch and knob?


----------



## Andykong

ArkNerevar said:


> @Andykong can we use the 6211 in the HA-6A? its similar to the 12AU7 but with lower max voltage ratings and higher Mu rating, thank you.


We do not recommend to use 6211 as replacement of 12AU7 in HA6A


----------



## ArkNerevar

@Andykong thanks for clarifying that for me.

I do have another issue I could really use your help regarding the rectifiers, I managed to recently nab a pair of Sylvanias on ebay and have now received them and found that they look identical to my RCAs, like exactly the same, so I asked Wes S who has considerable 22DE4 rolling experiance on the HA-300 thread, I showed him pictures of one of each side by side and he says they are both Sylvanias that RCAs plate structure has a different hole/crimp pattern, that would mean the pair that came with the amp branded RCA have all along been Sylvania, if hes right, can you have a look at these 2 for me please, thank you.

The one on the left is one of my new Sylvanias and the one on the right is one of my supplied with the amp RCAs.


----------



## Michaels1963

AudioPowerHead said:


> How do you actually dim the lights on the power switch and knob?


For the volume Knob and TR, UL button lights I Used Light Dims (lightdimes.com) for the power switch I used a Flat rubber washer from the hardware store Now I only see the sweet glow of the tubes and VU meters


----------



## Andykong

ArkNerevar said:


> @Andykong thanks for clarifying that for me.
> 
> I do have another issue I could really use your help regarding the rectifiers, I managed to recently nab a pair of Sylvanias on ebay and have now received them and found that they look identical to my RCAs, like exactly the same, so I asked Wes S who has considerable 22DE4 rolling experiance on the HA-300 thread, I showed him pictures of one of each side by side and he says they are both Sylvanias that RCAs plate structure has a different hole/crimp pattern, that would mean the pair that came with the amp branded RCA have all along been Sylvania, if hes right, can you have a look at these 2 for me please, thank you.
> 
> The one on the left is one of my new Sylvanias and the one on the right is one of my supplied with the amp RCAs.



Sorry, we don't validate third-party vacuum tubes for our customers.  Once we start this, we need to hire a new team of people to entertain similar user enquires.  We made over 400 models of tube amplifiers in our history and at least 100 of them are still working somewhere in the world, if we do this for HA-6A, we have to provide a similar service to all our tube amplifiers as well.


----------



## jamato8

Andykong said:


> Sorry, we don't validate third-party vacuum tubes for our customers.  Once we start this, we need to hire a new team of people to entertain similar user enquires.  We made over 400 models of tube amplifiers in our history and at least 100 of them are still working somewhere in the world, if we do this for HA-6A, we have to provide a similar service to all our tube amplifiers as well.


Ah, come on, just this once. lol kidding


----------



## ArkNerevar

@Andykong 
Im not asking you to validate third-party vacuum tubes, im asking you if the 22DE4s that were supplied with my amp are really RCAs or rebranded Sylvanias.


----------



## jamato8 (Dec 21, 2022)

ArkNerevar said:


> @Andykong
> Im not asking you to validate third-party vacuum tubes, im asking you if the 22DE4s that were supplied with my amp are really RCAs or rebranded Sylvanias.


It can go either way. Manufactures often manufactured tubes for other manufactures and sometimes it is hard to know for sure. RCA and GE did this a lot. I just got two nice 6F8G tubes yesterday that are NOS. One is Sylvania and one a National Union that says made by National Union both are exactly the same and even have the same date code, which is a 1 in a million chance as they came from different original sources and one is in a military box and the other in a standard consumer box.


----------



## jamato8




----------



## Andykong

ArkNerevar said:


> @Andykong
> Im not asking you to validate third-party vacuum tubes, im asking you if the 22DE4s that were supplied with my amp are really RCAs or rebranded Sylvanias.



This is like asking a car manufacturer whether they have used rebranded components in their production.  Please be realistic, the answer will always be genuine RCA from the official channel.


----------



## ArkNerevar

In my defence, the provided RCAs sure do look like what is pictured online and sold as Sylvania 22DE4s.


----------



## Michaels1963

ArkNerevar said:


> In my defence, the provided RCAs sure do look like what is pictured online and sold as Sylvania 22DE4s.


lol


----------



## Andykong

ArkNerevar said:


> In my defence, the provided RCAs sure do look like what is pictured online and sold as Sylvania 22DE4s.



Understand your concern, but how can we confirm that unless we perform a thorough validation of the Sylvania 22DE4s?


----------



## jamato8

Andykong said:


> Understand your concern, but how can we confirm that unless we perform a thorough validation of the Sylvania 22DE4s?


It can be very difficult. The other day, locally, I got a National Union branded 6F8G and a Sylvania both round plate. They would sell to each other and supply to each other all the time. So what are they, NU or Sylvania or maybe both are RCA, and by pure chance, they both have the same date code, and if I track down the date code, then most likely I would know who made them but even then, not always.


----------



## Andykong

jamato8 said:


> It can be very difficult. The other day, locally, I got a National Union branded 6F8G and a Sylvania both round plate. They would sell to each other and supply to each other all the time. So what are they, NU or Sylvania or maybe both are RCA, and by pure chance, they both have the same date code, and if I track down the date code, then most likely I would know who made them but even then, not always.



Exactly, and why would we as a manufacturer do something like that? We have to take the risk that a vacuum tube brand might not like what we said and jeopardized our supply chain.


----------



## Andykong

Thanks for being such an important part of the Cayin community. Hope you have a great Christmas and New Year!


----------



## Michaels1963

Andykong said:


> Thanks for being such an important part of the Cayin community. Hope you have a great Christmas and New Year!


 Happy Christmas @Andykong thanks for all information this year


----------



## Michaels1963

@Andykong I Tube Roll.  How many times do you think we can Insert and Pull-out tubes before there are contact problems with the socket and pins holding securely.
Do you use Socket Savers?

@Andykong Thanks for your Help


----------



## jamato8 (Dec 25, 2022)

Michaels1963 said:


> @Andykong I Tube Roll.  How many times do you think we can Insert and Pull-out tubes before there are contact problems with the socket and pins holding securely.
> Do you use Socket Savers?
> 
> @Andykong Thanks for your Help


Not Andy but a tube socket should last years. Some people though go nuts with pulling out tubes and putting them in and you could effectively shorten that to a couple of years but I wouldn't use a socket saver as there are more contacts and unknown wiring in the socket saver and they are primarily made for tube testers, which is where I use them, since for that, you are using a socket a lot but even at that, I have some testers that are 50 years old that are still fine with the original sockets. And of course, it depends upon the quality of the socket.

Also the ceramic sockets used by Cayin are nice quality and it is easy to tighten the sockets if need be.


----------



## ThanatosVI

Michaels1963 said:


> @Andykong I Tube Roll.  How many times do you think we can Insert and Pull-out tubes before there are contact problems with the socket and pins holding securely.
> Do you use Socket Savers?
> 
> @Andykong Thanks for your Help


Thousands of times actually. 
They should last many years, guess with normal usage you never have to worry about that.


----------



## Michaels1963

jamato8 said:


> Not Andy but a tube socket should last years. Some people though go nuts with pulling out tubes and putting them in and you could effectively shorten that to a couple of years but I wouldn't use a socket saver as there are more contacts and unknown wiring in the socket saver and they are primarily made for tube testers, which is where I use them, since for that, you are using a socket a lot but even at that, I have some testers that are 50 years old that are still fine with the original sockets. And of course, it depends upon the quality of the socket.
> 
> Also the ceramic sockets used by Cayin are nice quality and it is easy to tighten the sockets if need be.


Thanks for your reply, I didn't know you can tighten the Cayin sockets How is the procedure done?


----------



## Andykong

Michaels1963 said:


> @Andykong I Tube Roll.  How many times do you think we can Insert and Pull-out tubes before there are contact problems with the socket and pins holding securely.
> Do you use Socket Savers?
> 
> @Andykong Thanks for your Help





jamato8 said:


> Not Andy but a tube socket should last years. Some people though go nuts with pulling out tubes and putting them in and you could effectively shorten that to a couple of years but I wouldn't use a socket saver as there are more contacts and unknown wiring in the socket saver and they are primarily made for tube testers, which is where I use them, since for that, you are using a socket a lot but even at that, I have some testers that are 50 years old that are still fine with the original sockets. And of course, it depends upon the quality of the socket.
> 
> Also the ceramic sockets used by Cayin are nice quality and it is easy to tighten the sockets if need be.



Thanks, jamato8, that's a very good answer, back in 2000 when I was a reviewer in an audio magazine, I had pressure to have a lot of parties with a group of tube collectors, they basically believed that a nice tube amplifier is only a tube socket with gain, a platform to appreciate tube rolling, to maximize the differentiate and "amplify" their listening experience when they change to a different tube.   A lot of them used vintage tube amplifiers, and even with their exhaustive tube-changing pattern, they don't really care about the lifetime of the tube socket.  

Maybe we can put it this way, if you can wear out the socket of a decent tube amplifier like HA-3A or HA-6A, you should have enough experience or connection to replace the tube socket, either by yourself or with a capable technician that you feel comfortable to deal with, so that become a non-issue.


----------



## AudioPowerHead

This amp is really a gem. Besides its unique features such as the instantaneous TR/UL mode switch, el34/kt88 tube selector, it is also very responsive to tube rolling. Have been very much enjoying this amp so far in my chain without any usage problems or remarkable microphonics.

On tube rolling, am still at infancy stage of trial and error, have been doing a fair bit of reading and learning from others. Started the tube-maze journey as a tube newbie with this amp by making the initial choice between el34 vs kt88 tubes. Decided on the former as I was looking to find an even smoother and more visceral midrange sound signature to complement my SS amp. Then I bought a set of Mullard RI el34 and 12au7 to get an initial sense of how “better” could sound like. Not expecting much but these RI tubes are actually quite good sounding (good midrange and deep bass and quite detailed) despite being current production reissues. Using the popular 12au7 reference guide, tried swopping out the Mullard 12au7 and replaced with a pair of nos Sylvania 12au7. While the resolution, clarity and top end improved, it was however at the expense of warmth, richness and smoothness. Not my cup of tea, and I had since swopped back to the Mullard RI.

Not settling on “good” and aiming to have “great” auditory pleasure,I then decided to take the plunge to give the SE el34s a go, and boy am I glad to have taken this step. The sound improved with more clarity, refinement in the texture, more spacious and the bass slam became harder and tighter while not losing the core tonal characteristics of the Mullard input tubes. I hear a lot more sonic nuances that I did not notice before. Next, my nos pair of Mullard ecc82 arrived and the tracks I usually listen to became fuller and even smoother while still keeping the signature warmth sound. Together, these sets of power and input tubes has so much synergy that the sound (to me) that I am getting from my ZMFs is just beyond words. BTW, I have yet to roll the rectifier tubes as I am quite happy with the stock RCA nos tubes so far with its wide staging attribute. Nonetheless, will likely order some Raytheon/Sylvania 22de4s very soon, and then I shall see (hear) how they change the overall sound in terms of staging and bass response.

Hope everyone is enjoying their Cayin amps as much as I do. Happy tube-rolling and listening !


----------



## krude

AudioPowerHead said:


> This amp is really a gem. Besides its unique features such as the instantaneous TR/UL mode switch, el34/kt88 tube selector, it is also very responsive to tube rolling. Have been very much enjoying this amp so far in my chain without any usage problems or remarkable microphonics.
> 
> On tube rolling, am still at infancy stage of trial and error, have been doing a fair bit of reading and learning from others. Started the tube-maze journey as a tube newbie with this amp by making the initial choice between el34 vs kt88 tubes. Decided on the former as I was looking to find an even smoother and more visceral midrange sound signature to complement my SS amp. Then I bought a set of Mullard RI el34 and 12au7 to get an initial sense of how “better” could sound like. Not expecting much but these RI tubes are actually quite good sounding (good midrange and deep bass and quite detailed) despite being current production reissues. Using the popular 12au7 reference guide, tried swopping out the Mullard 12au7 and replaced with a pair of nos Sylvania 12au7. While the resolution, clarity and top end improved, it was however at the expense of warmth, richness and smoothness. Not my cup of tea, and I had since swopped back to the Mullard RI.
> 
> ...


Nice one, I'm enjoying GL ECC82 GL KT77 recently. It's a bit tuby with great sub bass extension giving a bottomless bass experience on Susvara. 

I also tried Black Treasure KT88Z, still need to give them some time but they seem to combine KT88 general performance with EL34 type of mids.


----------



## AudioPowerHead

krude said:


> Nice one, I'm enjoying GL ECC82 GL KT77 recently. It's a bit tuby with great sub bass extension giving a bottomless bass experience on Susvara.
> 
> I also tried Black Treasure KT88Z, still need to give them some time but they seem to combine KT88 general performance with EL34 type of mids.


Was initially planning to try the GL KT77, however changed my mind and went the path of SE el34 instead as I have strong inclination to find that magic midrange sound from this amp. The beauty of this amp is the TR/UL mode switch. On el34, I do sometimes find the top rolled off and lacking in the bass department. And that is when the UL mode comes in real handy to give that extra energy needed especially for genres or songs that needed that omph factor. That said, I may still try out the KT77 at some point in future. 

On KT88, I made that choice right from beginning that I will go with el34 as the baseline sound profile so will not be going there any time soon.

Thanks for your sharing


----------



## jamato8

I will have one on Thur. and have many NOS EL34, 6550, KT90 Yugoslavian (the best years) and many other NOS tubes to try out.


----------



## krude

AudioPowerHead said:


> Was initially planning to try the GL KT77, however changed my mind and went the path of SE el34 instead as I have strong inclination to find that magic midrange sound from this amp. The beauty of this amp is the TR/UL mode switch. On el34, I do sometimes find the top rolled off and lacking in the bass department. And that is when the UL mode comes in real handy to give that extra energy needed especially for genres or songs that needed that omph factor. That said, I may still try out the KT77 at some point in future.
> 
> On KT88, I made that choice right from beginning that I will go with el34 as the baseline sound profile so will not be going there any time soon.
> 
> Thanks for your sharing


By SE you mean Sophia Electric I presume?

I'll be getting both EL34 and KT88 from them in Jan or Feb 🍻


----------



## ThanatosVI

krude said:


> By SE you mean Sophia Electric I presume?
> 
> I'll be getting both EL34 and KT88 from them in Jan or Feb 🍻


Lovin the Sophia Electric KT88 and 12au7.

Other interesting new production Pentodes are the S4A 6550C Carbon and S4A KT88 Carbon (and S4A EL34 Carbon)
I just received the S4A 6550C Carbon and it's certainly a good tube. Rest is from the same series so probably compareable in quality. 

Or even the Linlai™ Global KT88-D
Also a new tube. Looks interesting but couldn't audition it yet


----------



## krude

ThanatosVI said:


> Lovin the Sophia Electric KT88 and 12au7.
> 
> Other interesting new production Pentodes are the S4A 6550C Carbon and S4A KT88 Carbon (and S4A EL34 Carbon)
> I just received the S4A 6550C Carbon and it's certainly a good tube. Rest is from the same series so probably compareable in quality.
> ...


I'll definitely have a look. I'm into warmer and full bodied sound with weighty bass, how's S4A with sound profile? I try to avoid bright tubes all together.


----------



## ThanatosVI (Dec 27, 2022)

krude said:


> I'll definitely have a look. I'm into warmer and full bodied sound with weighty bass, how's S4A with sound profile? I try to avoid bright tubes all together.


S4A has a weighty sound but also very clear.
Not very warm, quite neutral actually.

The EL34 could be warmer (usually they are, only for Sophia Electric I read that the EL34 is brighter than the KT88)


----------



## AudioPowerHead

krude said:


> By SE you mean Sophia Electric I presume?
> 
> I'll be getting both EL34 and KT88 from them in Jan or Feb 🍻


Yes and do share your impressions and comparisons when you get them.


----------



## AudioPowerHead

ThanatosVI said:


> Lovin the Sophia Electric KT88 and 12au7.
> 
> Other interesting new production Pentodes are the S4A 6550C Carbon and S4A KT88 Carbon (and S4A EL34 Carbon)
> I just received the S4A 6550C Carbon and it's certainly a good tube. Rest is from the same series so probably compareable in quality.
> ...


How would you describe the tonal characteristics of SE 12au7 ? Not much was written of it though. I was initially thinking of ordering a pair but decided to go with Mullard nos instead.


----------



## ThanatosVI

AudioPowerHead said:


> How would you describe the tonal characteristics of SE 12au7 ? Not much was written of it though. I was initially thinking of ordering a pair but decided to go with Mullard nos instead.


SE12au7 is very clear, detailed and well extended.

NOS Mullard should be a lot warmer and tubier.

Which NOS Mullard do you have (year, long plate or not?)


----------



## AudioPowerHead (Jan 5, 2023)

ThanatosVI said:


> SE12au7 is very clear, detailed and well extended.
> 
> NOS Mullard should be a lot warmer and tubier.
> 
> Which NOS Mullard do you have (year, long plate or not?)


That’s what I thought and may not suit my personal preference if it sounds like the Sylvania nos pair that I have.

I went for a standard Mullard nos pair which is one with dual marking of ecc82/cv491 military specs, ex-Blackburn probably from the 70’s.

Am also considering maybe the M8136 /CV4003 or e80cc as the next tubes to roll.

Edit: typo.


----------



## Newbman123

AudioPowerHead said:


> That’s what I thought and may not suit my personal preference if it sounds like the Sylvania nos pair that I have.
> 
> I went for an “entry-level” Mullard nos pair which is one with dual marking of ecc82/cv491 military specs, short plate, ex-Blackburn probably ‘76.
> 
> Am also considering maybe the M8136 /CV4003 or e80cc as the next tubes to roll. Do you have any reco ?


Anyone compare brimar cv4003 to mullard entry levels?


----------



## AudioPowerHead

Newbman123 said:


> Anyone compare brimar cv4003 to mullard entry levels?


Look forward to hear answers to this question too from other more experienced high rollers 

In the meantime, am enjoying very much my trinity combo of SE el34, Mullard nos ecc82 and RCA nos 22de4. In terms of preference, I find myself leaning towards the “warm, smooth and rich” quadrant in the 12au7 grid guide. Still continuing the tube discovery journey, and have just placed an order for a pair of RCA nos black plate 12au7. Hope the choice made is a good one for my taste. Quite inspired by the sharing in earlier posts from @krude and @shafat777 as I understand this is their much preferred input tube.

Happy listening and tube rolling all !


----------



## ThanatosVI

Anyone know where to still get Brimar CV4003 and Mullard CV4003 56-57 from trustworthy sources?


----------



## Toonartist

Hot Rox Uk sell Brimar 12au7 CV4003, Mullard ECC82 / M8136. I believe the Mullards will be 1970's onwards as the ones I've received from them have the new shield logo. But, every tube I've received from them works without issue and they've been quick to dispatch!

There is also a guy on eBay selling 1960's Mullard M8136. He's not exactly the best in terms of comms and speed of dispatch but I've always received the tubes and they've been NOS in original box, wrapping etc so far.


----------



## busseysound

ThanatosVI said:


> Anyone know where to still get Brimar CV4003 and Mullard CV4003 56-57 from trustworthy sources?


I've got a pair of CV 4003 that are hardly used and tested in the HA-6A.  Just send me a PM if interested.


----------



## Newbman123

busseysound said:


> I've got a pair of CV 4003 that are hardly used and tested in the HA-6A.  Just send me a PM if interested.


Didn't like them?


----------



## busseysound

Newbman123 said:


> Didn't like them?


I used to use them in my Schiit MJ2.  Lots of punch.  Can we use them adapted in the HA-6A?  I really love my Telefunken ECC802S and I'm going to try the E80CC when they come in.


----------



## Newbman123

busseysound said:


> I used to use them in my Schiit MJ2.  Lots of punch.  Can we use them adapted in the HA-6A?  I really love my Telefunken ECC802S and I'm going to try the E80CC when they come in.


Do mullards have that much punch? I tried the brimar on an auris euterpe and then i always wanted one but I'm also wondering if i should just get some mullards because I'm not able to get my hand on brimar.


----------



## Newbman123

Toonartist said:


> Hot Rox Uk sell Brimar 12au7 CV4003, Mullard ECC82 / M8136. I believe the Mullards will be 1970's onwards as the ones I've received from them have the new shield logo. But, every tube I've received from them works without issue and they've been quick to dispatch!
> 
> There is also a guy on eBay selling 1960's Mullard M8136. He's not exactly the best in terms of comms and speed of dispatch but I've always received the tubes and they've been NOS in original box, wrapping etc so far.


Are those nos brimars?


----------



## Newbman123

busseysound said:


> I used to use them in my Schiit MJ2.  Lots of punch.  Can we use them adapted in the HA-6A?  I really love my Telefunken ECC802S and I'm going to try the E80CC when they come in.


I think they can considering the site mentions cv4003 in the list of accepted tubes


----------



## AudioPowerHead

busseysound said:


> I used to use them in my Schiit MJ2.  Lots of punch.  Can we use them adapted in the HA-6A?  I really love my Telefunken ECC802S and I'm going to try the E80CC when they come in.


Would you describe the Telefunken ecc802s as high resolution, transparent and/ detailed, articulate ? Is it neutral skewed ? 

@Andykong has recently confirmed e80cc could be used on both ha6a/ha3a, this would be an interesting tube to try. Which brand you going for ? I know many on ha3a thread seem to like it very much.


----------



## cerealmilk

man i want to try this amp so bad with these babys its a shame i dont have my Cayin when i got these


----------



## busseysound

AudioPowerHead said:


> Would you describe the Telefunken ecc802s as high resolution, transparent and/ detailed, articulate ? Is it neutral skewed ?
> 
> @Andykong has recently confirmed e80cc could be used on both ha6a/ha3a, this would be an interesting tube to try. Which brand you going for ? I know many on ha3a thread seem to like it very much.


The Telefunken ECC802S is VERY balanced and neutral in my opinion.  Very clear, articulate, basically amazing (and I'm pretty picky).  Unfortunately they aren't cheap.  Make sure (if you decide to get a pair) that it reads exactly ECC802S on the bottle.  There are also some fakes out there, so if you're unsure about a pair for sale post them here and I'll do what I can to take a look and give my opinion.  When they come in I'll be trying the Telefunken and Tungsram E80CC in the 12AU7 slots.  I'll share my opinion as I've heard that they are better than using 12AU7's or even ECC802S tubes.


----------



## AudioPowerHead

busseysound said:


> The Telefunken ECC802S is VERY balanced and neutral in my opinion.  Very clear, articulate, basically amazing (and I'm pretty picky).  Unfortunately they aren't cheap.  Make sure (if you decide to get a pair) that it reads exactly ECC802S on the bottle.  There are also some fakes out there, so if you're unsure about a pair for sale post them here and I'll do what I can to take a look and give my opinion.  When they come in I'll be trying the Telefunken and Tungsram E80CC in the 12AU7 slots.  I'll share my opinion as I've heard that they are better than using 12AU7's or even ECC802S tubes.


Cool thanks for your sharing and reminder on possible fakes. 

Will be great to hear your feedback on the e80cc vs 12au7/ecc802s.


----------



## jamato8 (Dec 30, 2022)

I have some 6085 NOS I will be using. I have Tungsram and Phillips. They were the main manufacturer of the tube. I also have some NOS in Telefunken Smooth plate but none of the ultra fancy ones that were the special select mega bucks models. lol

I will have the HA-6A today. Then to burn it in.


----------



## AudioPowerHead

jamato8 said:


> I have some 6085 NOS I will be using. I have Tungsram and Phillips. They were the main manufacturer of the tube. I also have some NOS in Telefunken Smooth plate but none of the ultra fancy ones that were the special select mega bucks models. lol
> 
> I will have the HA-6A today. Than to burn it in.


Welcome to the club !


----------



## jamato8 (Dec 30, 2022)

Put some Tungsram in with the stock EL84s, very good sound. Have some KT99 Yugo in now but don't care for them. Good tube not liking this combination. I have some early versions, the really excellent one, slightly used and NOS. I think the stock EL34s are a good tube with excellent slam etc. I have many power tubes of all types in NOS to try out. Should be fun.

Trying some Amperex Bugle Boy now Brown base. XF4, I have the XF2 also but these need some play time anyway. Hummm. More bass heavy but they need some time. I think the stock EL34s are pretty good.


----------



## AudioPowerHead

jamato8 said:


> Put some Tungsram in with the stock EL84s, very good sound. Have some KT99 Yugo in now but don't care for them. Good tube not liking this combination. I have some early versions, the really excellent one, slightly used and NOS. I think the stock EL34s are a good tube with excellent slam etc. I have many power tubes of all types in NOS to try out. Should be fun.
> 
> Trying some Amperex Bugle Boy now Brown base. XF4, I have the XF2 also but these need some play time anyway. Hummm. More bass heavy but they need some time. I think the stock EL34s are pretty good.


You seem to have a rich stash of tubes to play with   Such a great position to be in. Happy rolling !


----------



## jamato8

Also sounding good with some Svetlana Winged C EL34 tubes from 1999.


----------



## Z_Showmaster

Shame not to join in the fun – I've a pair of JJ ECC802S incoming, and I'm very much looking forward to hearing the long-plate effect in my amp.

Have a Happy New Year and a great 2023!


----------



## Andykong

jamato8 said:


> Put some Tungsram in with the stock EL84s, very good sound. Have some KT99 Yugo in now but don't care for them. Good tube not liking this combination. I have some early versions, the really excellent one, slightly used and NOS. I think the stock EL34s are a good tube with excellent slam etc. I have many power tubes of all types in NOS to try out. Should be fun.
> 
> Trying some Amperex Bugle Boy now Brown base. XF4, I have the XF2 also but these need some play time anyway. Hummm. More bass heavy but they need some time. I think the stock EL34s are pretty good.



Wow, a new HA-6A alongside your HA-300MK2?  A quick look at your profile signature suggested that this will be your 8th vacuum tube headphone amplifier.  Interesting, I hope you'll enjoy the tube rolling fun with HA-6A, I guess this is the main reason for you to get the HA-6A.  I like your approach, despite you have very nice collection of EL34, you have given the stock tube a fair chance.


----------



## jamato8

Andykong said:


> Wow, a new HA-6A alongside your HA-300MK2?  A quick look at your profile signature suggested that this will be your 8th vacuum tube headphone amplifier.  Interesting, I hope you'll enjoy the tube rolling fun with HA-6A, I guess this is the main reason for you to get the HA-6A.  I like your approach, despite you have very nice collection of EL34, you have given the stock tube a fair chance.


I typed EL84, that would be a trick, a wonderful tube but not up to this job. lol

The stock tube really is very good. I tried the XF4, 2 NOS and nice but today trying some XF2 NOS. Too bad they are so expensive and really, now days, hard to know if you are really getting NOS. I test all my tubes but these latest I have had for many years and they even have the same date code.

I think I have 8 tube amps, no 10 but 2 of those are strictly speaker amps, a pair of mono blocks and a very nice stereo amp. All highly modified.

Anyway it is all good and in the cool weather, having one or two amps on, keeps my working room warmer. :^)

Yes, main reason, only a pair of power tubes are needed and I have many pairs of some nice tubes and then a bunch of NOS SED winged C EL34 from 2003.


----------



## jamato8

The Real Bugle Boy. XF2 two with same date codes NOS. Dust an all. lol


----------



## jamato8

A very nice combination. Tuneful and great impact. 5881 Tung-Sol and 12AU7 Yugoslavian smooth plate.


----------



## AudioPowerHead

Have been trying different preamp tubes lately and I think I am quite settled with both pairs of RCA nos 50s black plate 12au7 and Mullard nos 70s ecc82; on rotations playing on my ha-6a.

My preference is skewed towards that of a warm, smooth and rich sound and both of these tubes caters to my needs very well. Here’s how I perceive the sound of these tubes:
1) Mullard- warm, detailed, liquid midrange, silky highs and deep bass
2) RCA- warm, detailed, clear midrange, sparkling highs and rich thumping bass. 

Both have the sweet and rich harmonic tones. While there are many similarities between both, I find the Mullard has slightly more forward mids while RCA has relatively wider staging. 

My listening sessions on ha-6a were paired with SE el34 which provided even more vivid details, tighter bass, more air and RCA nos 22de4 which further enhances the staging. A perfect concoction of tubes with a final tone that delivers maximum audio pleasure for me listening with my ZMF VO.

I think sonic happiness is when we are able to dial in to the exact sound profile we sought for. And I love my Cayin for the fact that it provided me with the perfect platform in doing so without wasting too much time and money in the process of finding the right combinations of tubes and sound that is right for me.


----------



## Michaels1963

Has anyone used "Sophia Electric" EL34 and KT88 tubes what are your opinion?​


----------



## shafat777

Michaels1963 said:


> Has anyone used "Sophia Electric" EL34 and KT88 tubes what are your opinion?​


Sophia kt88 tubes are whats powering my ha6a. They add balance in both too and bottom end. Bass has more texture and overall the sound is smooth/warm. I like these over my gold lion kt88 as well as psvane kt88 t2.


----------



## Michaels1963

shafat777 said:


> Sophia kt88 tubes are whats powering my ha6a. They add balance in both too and bottom end. Bass has more texture and overall the sound is smooth/warm. I like these over my gold lion kt88 as well as psvane kt88 t2.


Thanks for the reply What 12AU7 tubes are you using to get that sound


----------



## shafat777

Michaels1963 said:


> Thanks for the reply What 12AU7 tubes are you using to get that sound


Right now i m testing between 3 sets. 1963 Mullard NOS ECC82, 67 Telefunken ECC802s and Brimar 13D5 NOS. The Mullard is not broken in yet, but the other two are. So far the telefunken goes really well with the SE KT88. The Brimar is warm, may be a bit too warm with Sylvania 22de4 tubes, but it sounds amazing with stock RCA 22de4 rectifiers.


----------



## busseysound

shafat777 said:


> Right now i m testing between 3 sets. 1963 Mullard NOS ECC82, 67 Telefunken ECC802s and Brimar 13D5 NOS. The Mullard is not broken in yet, but the other two are. So far the telefunken goes really well with the SE KT88. The Brimar is warm, may be a bit too warm with Sylvania 22de4 tubes, but it sounds amazing with stock RCA 22de4 rectifiers.


I'll add another vote for the Telefunken ECC802S.  Very balanced and neutral.


----------



## ThanatosVI

Michaels1963 said:


> Has anyone used "Sophia Electric" EL34 and KT88 tubes what are your opinion?​


I'm using the Sophia Electric KT88.
They have a very detailed and spacious presentation with great frequency extension.

Only slight warmth, like common on modern tubes and amps. Not the gooey vintage warmth.

I read that the EL34 are actually brighter than the KT88, which potentially Puts them in a neutral Spot with great extension.
Usually EL34 bring more warmth than KT88, therefore I consider it worth mentioning.
I could never try the Sophia Electric EL34 myself tho.

I pair them with Sophia Electric 12au7.

Tl;Dr among the best new production tubes available


----------



## OctavianH

Michaels1963 said:


> Has anyone used "Sophia Electric" EL34 and KT88 tubes what are your opinion?​


I used Sophia Electric EL34 and those were some of my brightest EL34 from collection. Very good detail and sharp sound, but not quite what you would expect from EL34. I write from memory because I sold them.


----------



## krude

ThanatosVI said:


> I'm using the Sophia Electric KT88.
> They have a very detailed and spacious presentation with great frequency extension.
> 
> Only slight warmth, like common on modern tubes and amps. Not the gooey vintage warmth.
> ...


How bright are the SE KT88? I am really bright treble averse and prefere smooth (but detailed) treble. Would you be able to compare them with GL KT88? (which is on the edge of my tollerable brightness, but at least has good bass)


----------



## ThanatosVI

krude said:


> How bright are the SE KT88? I am really bright treble averse and prefere smooth (but detailed) treble. Would you be able to compare them with GL KT88? (which is on the edge of my tollerable brightness, but at least has good bass)


I wouldn't call them bright. 

I can compare them, since I have both here, just have to find some time to do so


----------



## jamato8

I had some NOS Sovtek KT88 from 1999. Seeing how they sound. But so far the XF2 Mullards have been the best.


----------



## shafat777

Just popped in a set of NOS 63 Philips MIniwatts SQ E80CC tubes in my amp so far it has been a revelation. This is the widest soundstage i have ever heard in this amp, period. There is also a noticeable addition to clarity and crispness in the sound. First impression, these are wonderful set of tubes that pairs really well with this amp. Until this, i had only used 12au7 variant tubes and the e80cc is far better in just about everything. Cant wait to see how much more burning in needed before it settles down and sounds as it should.


----------



## jamato8

shafat777 said:


> Just popped in a set of NOS 63 Philips MIniwatts SQ E80CC tubes in my amp so far it has been a revelation. This is the widest soundstage i have ever heard in this amp, period. There is also a noticeable addition to clarity and crispness in the sound. First impression, these are wonderful set of tubes that pairs really well with this amp. Until this, i had only used 12au7 variant tubes and the e80cc is far better in just about everything. Cant wait to see how much more burning in needed before it settles down and sounds as it should.


Do you notice much gain difference?


----------



## shafat777

jamato8 said:


> Do you notice much gain difference?


Not really. Maybe a tiny tiny tad bit but definitely not a deal breaker but the sound improvement is incredible


----------



## jamato8 (Thursday at 11:36 PM)

shafat777 said:


> Not really. Maybe a tiny tiny tad bit but definitely not a deal breaker but the sound improvement is incredible


They draw twice the current I think I read that it works ok. That was in the thread a while back. I was using Tungsram now that I think of it. Using some Sylvania 6189 right now, triple mica 1962, great impact and nice tubes. Also running some KT90s in triode mode, version 2.


----------



## jamato8 (Yesterday at 6:10 PM)

So I put in some 7062 Philips SQ E180CC (good sub for the 12AT7) to see how they would sound. The current draw for the filament is just a little higher than a 12AU7 so that isn't a concern and lower than the 7085 (which I tried again but didn't care for). So at first noisy, expected as they needed to burn in for an hour or so to burn off any gasses and to activate the getter. Nice and quiet now and shaping up very well. I find them more energetic than most any 12AU7 and far less expensive than NOS 12AU7 better tubes. They can microphonic but then you don't normally go around tapping on the tube or chassis and if you do, that is your issue and not the tube. Bass is good and fast, piano is realistic and voice is extremely good. Using it in conjunction with the KT90 Yugo version 2 in triode (to me, over the years, the KT90 sounds better in triode mode -strapping).


----------



## krude

Im rediscovering Black Treasure KT88Z with GL 12au7. BT KT88Z doesn't sound like a typical KT88. It's darker with creamy mids, smooth treble and deep and strong bass. Does have bass bloom to my ears. It's more of a vintage flavoured romantic sound, but with good technicalities and punch. GL 12au7 give it a bit of bite as well. It's a good alternative to romantic EL34s. 

Now I'm wondering about KT88T 🙃


----------

