# New Leckerton UHA760 Coming Soon!!



## Shini44

"
The UHA760 USB DAC and amplifier combo features digital upsampling to 192 kHz, digital volume control, crossfeed, and a three-position gain selector. The UHA760 can be powered by USB or by its internal rechargeable battery.

The UHA760 uses an asynchronous sample rate converter (ASRC) to upsample the USB audio stream to 192 kHz.* The output side of the ASRC is clocked by a stable, low-jitter crystal oscillator. This has the effect of decoupling the jitter which exists on the streaming USB audio signal, resulting in a cleaner and more stable digital signal to the DAC. The ASRC also has the effect of pushing the high-frequency image signals (inherent to all DACs) away from the audio band. This allows the DAC chip to use a gentler low-pass filter which, in turn, avoids the pre-ringing (or pre-echo) resulting from the steep low-pass filters commonly used at lower sample rates such as 44.1 kHz or 48 kHz.

The digital volume control provides a stable and centered stereo image across the entire volume adjustment range, even at the lowest settings. Adjustment steps are 1 dB.

The crossfeed function feeds a delayed and filtered version of the sound in each channel to the opposite ear, mimicking the way we hear sounds in a natural acoustic environment. This helps to reduce the fatigue and unnaturalness produced by some headphones, especially on recordings with wide stereo separation. The crossfeed feature allows three settings: high, low, and bypassed.

Like the UHA-6S MKII, the UHA760 includes a charge enable switch. When disabled, the UHA760 operates entirely from its internal battery, enabling use with tablets and other devices which limit USB output power."

 

I was looking to buy my 3rd Uha-6.MKII , yes the 3rd one just keep coming back to this great amp, and i saw this in the product list, This company indeed got one of the best amplifiers if not the best for its price, got to like the fact that there is 3 gains options, maybe it is due a lot of us CIEMs owners asking neck to lower the gain for UM Miracle etc, seems like neck decided to add this new gain option to avoid making people lose money and time wasted to adjust their MK II, nice idea indeed.


----------



## RAFA

That is cool news. Is there any more information on the internals?


----------



## Shini44

non so far  i thought that people knew about that product, but there were no posts about it so i made one, i want to get one :< was about to buy the Uha again but i think i will wait for few weeks to hear more about this one.


----------



## RAFA

shini44 said:


> non so far  i thought that people knew about that product, but there were no posts about it so i made one, i want to get one :< was about to buy the Uha again but i think i will wait for few weeks to hear more about this one.




I will wait for a review and for the price. Last time with UHA6, I was pretty much hyped up, till the price gave me a cold shower.

I think the main feature, that makes this one interesting is its crossfeed.


----------



## Shini44

rafa said:


> I will wait for a review and for the price. Last time with UHA6, I was pretty much hyped up, till the price gave me a cold shower.
> 
> I think the main feature, that makes this one interesting is its crossfeed.


 
 will for me the Uha 6 MKII is really really good, the Uha 6 was kind of a fail so you were more like a victim  yet feel free to check  project86's review on the MKII, he is one of the best reviewers on the site.


----------



## sq3rjick

I'm very interested in this. I just recently picked up a 6S.MKII and I'm very happy with it.  But if the new 760 is even better, I might just have to pick up one of them, as well.


----------



## thegrobe

An e-mail that went out today regarding the 760:

The new UHA760 Upsampling USB DAC and Amplifier will be shipping this fall
I'm excited to share some new information about the upcoming UHA760 Upsampling USB DAC and Amplifier combo. I'm currently working on a few final design tweaks of the pre-production model. As soon as I have everything to my liking, I'll be starting up production, with the first units expected to ship later this fall.

I do a lot of my listening over USB using source material sampled at 44.1 kHz (like my CD collection, Spotify streaming, etc). With the UHA760, my goal is to provide a high-end amp geared for that type of use. I've included an asynchronous upsampler because this enables some improvements to the digital-to-analog conversion process. I've incorporated digital volume control and a three-position gain adjustment because it allows precise control of the volume setting and guarantees channel matching even at the lowest volume setting (great for sensitive IEMs!). I've included a two-position crossfeed control with bypass, handy for reducing listener fatigue on recordings with hard panning or excessive stereo separation.

For more information on the features mentioned here and some additional enhancements you can expect to see on the UHA760, take a look at my recent blog post:
http://www.leckertonaudio.com/blog/2013/10/a-look-at-the-new-uha760-upsampling-usb-dac-and-amp

The UHA760 will be regularly priced at $439, and I will be offering a special, limited-time introductory price of $379. Details of that sale will be made available on the website and on this email list.

Nick
Leckerton Audio, Inc.
www.leckertonaudio.com


----------



## musicheaven

shini44 said:


> non so far  i thought that people knew about that product, but there were no posts about it so i made one, i want to get one :< was about to buy the Uha again but i think i will wait for few weeks to hear more about this one.




As theGrobe mentioned above, news is out. Can you please add Nick's blog description which is quite detailed and informative about the amp, here is the info:

A look at the upcoming UHA760 USB DAC and Amp

Here's a look at my latest design, the UHA760. My goal with this model is to provide a high-end USB DAC and amplifier combo geared for those who, like me, listen mostly to source material recorded at 44.1-kHz (ripped CDs, Spotify, etc). The UHA760 can handle USB audio rates up to 16-bit/48-kHz. It includes an asynchronous sample rate converter (ASRC) which upsamples the digital audio to 192-kHz. The upsampling process, while not intended to create or replace audio signal content, does have some nifty benefits: because it is an asynchronous process, it isolates the DAC chip from jitter on the USB interface; it also shifts the digital filter in the DAC away from the audio band, allowing for a higher performance external filter. In addition to the ASRC, the UHA760 includes digital volume control and adjustable crossfeed with bypass.

Asynchronous Upsampling

There are numerous DAC designs on the market with upsampling capability, but it's not always clear what upsampling is or why it might be desirable. The upsampling process creates interpolated digital audio samples which sort of "fill in" the space between the original samples. Suppose the original sample rate is 48 kHz. The output of the SRC, running at 192 kHz, would have four samples for every one sample in the input signal.

Although it may seem counterintuitive, the ASRC is not actually creating signal content or replacing anything lost along the way. A digital audio signal at 44.1 kHz can only contain frequencies up to about 22 kHz. After upsampling this signal to 192 kHz, it still only contains frequencies up to 22 kHz. Nothing is added. So why bother? The benefits, it turns out, are a bit more indirect.

USB Jitter Isolation

The first benefit is isolation from USB interface jitter. The USB data stream can be jittery, meaning the digital bits don't arrive at an exact, fixed rate. The edge of a data bit can arrive slightly early or slightly late, depending on when the host (i.e., the computer) sends it. Normally this wouldn't affect the actual audio signal content - as long as the USB interface chip can determine whether the bit is a 1 or a 0, there's nothing lost. And there's usually plenty of margin to accomplish this with practically no errors. The trouble occurs when the jittery USB data stream is used to generate the clock signals that are needed by the DAC. This is how the jitter can get translated into something potentially audible, such as increased distortion. Using an asynchronous SRC means the clock signals for the DAC don't need to be derived from the USB data stream. Instead, the clock signals are generated by an on-board crystal oscillator which has very low jitter and is very stable. This prevents any jitter on the USB interface from having an effect on the digital-to-analog conversion.

Improved Digital Filter Response

The second benefit has to do with something called an interpolation filter. This is a digital filter which comes into play whenever a digital signal is upsampled. Upsampling creates unwanted, high-frequency signals, and the job of the interpolation filter is to remove these signals. This filter is present not only in the sample rate converter chip, but also in the DAC chip itself. Most modern DAC chips use a technique called sigma-delta modulation, and this involves upsampling the digital signal to a very high sample rate, usually somewhere between 1 and 6 MHz. The interpolation filter in the DAC chip removes anything higher than about half of the sample rate, while ideally leaving everything in the audio band untouched. So if we start with a digital signal at 44.1 kHz, the interpolation filter must let through audio at 20 kHz while removing everything above about 22 kHz. This requires a steep filter, and the more processing power given to this filter, the better job it can do. The approach taken by some high-end DAC manufacturers these days is to run the DAC chip at a high sample rate and let some other, more powerful processor handle the steep filtering. Running the DAC chip at 192 kHz means its interpolation filter can be configured to have a high cut-off frequency and a very gentle (i.e., non-steep) roll-off. This essentially pushes the effects of the filter away from the audio band.

The UHA760 uses the CS8422 ASRC chip from Cirrus Logic. The interpolation filter in this chip has some advantages over the filter in the CS4398 DAC chip. The CS8422 filter has almost no pre-ringing in the impulse response, for example. The debate over this is ongoing, but DAC designers suspect that pre-ringing can have negative audible effects because it produces a sort of "time smear". Pre-ringing generally does not occur in nature, so it sounds especially strange to our ears. In addition to minimal pre-ringing, the CS8422 also provides near-constant group delay across the audio band, meaning that all frequencies are delayed almost equally through the filter.

Digital Volume Control

The advantage of the digital volume control is that it provides excellent channel-to-channel level matching, better than almost any analog potentiometer. Even a high-quality analog pot can exhibit some channel level mismatch at the ends of the adjustment range (near minimum volume, for example). The digital volume chip in the UHA760 guarantees channel-to-channel matching within +/-0.5 dB at all settings, even minimum and maximum volume settings. My lab measurements show the performance is typically even much better than that. What this all means is that the stereo image in your phones remains stable and centered as you adjust the volume, even if you are using high-sensitivity IEMs which require relatively low levels to drive.

An analog potentiometer is used as the control mechanism on the UHA760, but instead of connecting directly to the amplifier circuitry, the potentiometer provides a signal to the microcontroller which is then converted into the control signal for the digital volume chip.

Some users of the UHA-6S.MKII have commented that the volume knob is a bit too easy to turn, sometimes resulting in unintentional adjustments when the amp is in a pocket or bag. The UHA760 uses a smaller knob and a potentiometer with higher physical resistance, and this should help reduce the chance of an accidental adjustment.

Crossfeed

The crossfeed in the UHA760 is an analog type, very similar in design and performance to the crossfeed in the UHA-4. The UHA760 offers two levels of crossfeed along with a true bypass.

Improvements to Power Supply and Turn-On Pop

The UHA760 has some additional circuitry improvements over the UHA-6S.MKII. The UHA760 includes an improved power supply design with better regulation and lower noise. Along with an increase in total power supply capacitance, this new design provides supply voltages to the audio amplifier circuitry which are more stable and less susceptible to ripple caused by high-amplitude transients in the audio signal.

Just prior to the headphone jack of the UHA760 is a mechanical relay. This relay opens automatically during turn-on and turn-off, preventing pops or clicks at the headphones when flipping the power switch.

Available This Fall

I'm currently working on performance characterization of the pre-production version of the UHA760. At this point, all the kinks have been worked out, and the amp is just about ready to begin production. The amp will be available to purchase later this fall. The regular price will be $439. I will be offering a limited-time introductory price of $379.

Following the UHA760

The UHA760 lacks S/PDIF optical and coax inputs, and this is mostly due to a lack of room on the circuit board for the connectors. I know these types of inputs are useful for a lot of folks, so I'm planning a model based on the UHA760 which will be a bit larger in size but will also include S/PDIF inputs, a DAC line output, and socketed op-amps. Support for 24-bit/192-kHz USB streaming is another feature you can expect to see soon.


----------



## kimvictor

Get hyped! Nick might consider trade in program as well!


----------



## Bazirker

So expensive...a big jump in cost from their current amps.  We'll have to see if the improvements are worth it...


----------



## cooperpwc

The crossfeed is very interesting combined with the digital volume control. I would like to see a version without the DAC.
  
 Worth monitoring...


----------



## Gorillaz

cooperpwc said:


> The crossfeed is very interesting combined with the digital volume control. I would like to see a version without the DAC.
> 
> Worth monitoring...
> 
> I was thinking the same, it might be even smaller and perfect.


----------



## yaluen

Three position gain switch, digital volume control, crossfeed. I think these address many of the usability issues us UHS-6S.MKII users have with the amp/dac. I emailed Nick with a few questions about the UHA760 and I thought I'd share his responses here, hope he doesn't mind.
  


> 1) That is correct, the UHA760 does not include socketed op-amps due to space limitations on the circuit board. The next model I mentioned
> will be slightly larger in order to accommodate socketed op-amps and
> the additional input/output. The UHA760 has an amplifier circuit which
> is very similar in design to the UHA-6S.MKII. There are some
> ...


----------



## musicheaven

yaluen said:


> Three position gain switch, digital volume control, crossfeed. I think these address many of the usability issues us UHS-6S.MKII users have with the amp/dac. I emailed Nick with a few questions about the UHA760 and I thought I'd share his responses here, hope he doesn't mind.




Thanks truly appreciate your convo with Nick.

I am waiting for the full blown UHA 760 with coax in. As far as DAC connectivity with the USB world, I am not that anxious for an implementation of it. I got other amps I can use for that specific purpose, no need to add to the otherwise crowded collection.

Now crossfeed is definitively interesting but what steals the show is digital volume control, I can't go in bed without a good amp with digital control because you want to listen to a very low music level without channel imbalance else your left brain will ask what are you listening to while the right brain is sleeping


----------



## yaluen

Yeah, the new gain switch plus digital volume control is a great boon for low level listening, very nice indeed.
  
 Looking at the UHA760 product page, it seems it has been updated by Nick, I've copypasted the additions here.
  
 Of note:

Default gain values of -12dB/0dB/+12dB (0.25x/1x/4x)
AD8610 output opamps
+/-7 VDC voltage rails (vs +/-6 VDC on the UHA-6S.MKII)
Battery life of 12 hours, analog input; 6 hours, USB input (vs >30 hours typical, analog input; >10 hours typical, S/PDIF input on the UHA-6S.MKII. I guess battery size was sacrificed in favour of more room on the board for features)
  
*Features:*


> *Asynchronous upsampling to 192 kHz.* Upsampling provides isolation from jitter on the USB interface; it also shifts the digital filter in the DAC away from the audio band, allowing for a higher performance external filter. *High-performance Cirrus Logic DAC.* The CS4398, Cirrus Logic’s flagship digital-to-analog converter, is a long-time favorite of audio enthusiasts due to its exceptional performance and audio quality.
> *Digitally-controlled volume.* Volume adjustment is controlled digitally in 1-dB steps, with excellent channel-to-channel level matching across the entire volume adjustment range.
> *Three-position gain control.* Optimize the volume range for your headphones or earphones by choosing from three gain settings.
> *Adjustable crossfeed with bypass.* The crossfeed circuit sends a delayed and filtered version of the sound to the opposite ear, mimicking the way we hear in a real acoustic environment. This reduces the unnatural sound which can occur with heavily-panned recordings.
> ...


 
  
*Specifications:*


> Max output power (1% THD, 1 kHz):
> 30 mW into 16 ohms
> 55 mW into 32 ohms
> 100 mW into 62 ohms
> ...


 
  
*Summary:*


> 16-bit/48kHz USB digital audio
> Asynchronous upsampling to 192 kHz
> 1/8″ analog input
> Automatic input selection
> ...


----------



## fnkcow

Oh boy oh boy!
 Hope its amp can one-up the Quickstep!
 High expectations!


----------



## yaluen

Looks like an early December release date.


----------



## musicheaven

Yep December 11th to be precise and a nice pre-order price. I am waiting for the UHA 760 +


----------



## Bazirker

I'm looking at the specs and don't see anything for high impedance phones like my 600 ohm DT990'S. The UHA-6S.MKII does an OK job of driving it, although I was hoping that with an extra gain position that the app would put out considerably more juice on that top setting. Gonna have to decide if I'm going to sell my current amp to get this one...


----------



## yaluen

The only reason to go for the UHA760 would be for its additional features as there doesn't seem to be any difference in maximum power output between the two. Most likely you can expect the same performance in terms of that. However, high gain on the MKII is +18dB (8x) while it on the UHA760 is +12dB (4x) so if you're needing to dial the volume pot way up to drive your DT990s even in high gain, you would definitely want to have the gain on the UHA760 adjusted.


----------



## yaluen

Pre-order page is up, with an estimated ship date of December 11. Even though the output op-amps aren't socketed, it looks like you're given a choice in which ones you want installed in the unit.


----------



## Kendoji

I'd love to get one but really can't justify upgrading from my UHA-6S.MKII. Can't wait to read some reviews though.


----------



## kimvictor

kendoji said:


> I'd love to get one but really can't justify upgrading from my UHA-6S.MKII. Can't wait to read some reviews though.


+1


----------



## robm321

+2 I bought the UHA-6s mkii because it was a great value. There is a lot of competition at the UHA760 price.


----------



## fnkcow

+3. Definitely keeping UHA760 on my watchlist


----------



## yaluen

As I'm quite happy with the MKII at the moment, I'll also be waiting for impressions. Hopefully someone will be able to compare it to the MKII and tell us if signal upsampling and the improved power supply brings noticeable audible improvement. Also would like to see pics of the PCB


----------



## Bazirker

All of this. Love my MK II, but I never use anything except the USB input so the 760 is appealing. Wait for reviews, but pay a higher price (potentially)? Tough choice...


----------



## thegunner100

If it's a $100 upgrade by trading in my uha-6s mkii, i'd do it. I never use the leckerton as a dac, but maybe the dac performance may be improved a little so that it's actually worth using.
  
 Edit: for the version with optical and coax inputs, not the standard one.


----------



## lee730

My Leckerton 760 was mailed yesterday. Hoping to get it by this Saturday . Will compare it to my T1 once I receive it.


----------



## cooperpwc

fnkcow said:


> Oh boy oh boy!
> Hope its amp can one-up the Quickstep!
> High expectations!


 
  
 One-up the Quickstep for SQ? We will see about that. Nonetheless the size, features and DAC could make the UHA760 very attractive.


----------



## lee730

cooperpwc said:


> One-up the Quickstep for SQ? We will see about that. Nonetheless the size, features and DAC could make the UHA760 very attractive.


 
  
 So the UHA6 MKII didn't already do that? .


----------



## cooperpwc

lee730 said:


> So the UHA6 MKII didn't already do that? .


 
  
 YMMV.


----------



## lee730

cooperpwc said:


> YMMV.


 
  
 lol


----------



## GeoD

My UHA760 arrived in the mail today.  I listened to my UHA-6S.mkII extensively over the past 2 months at work on a daily basis.  The headphones I use to listen are a pair of Brainwavz B2 IEMs.  I listen almost exclusively to streaming music on soundcloud, di.fm and youtube, which was what attracted me to the UHA760.
  
 Before you read any of this please note that my UHA-6S.mkII has the default AD8610ARZ op-amp, where I chose the OPA209AID op-amp for the UHA760.  I won't know what is the cause of the differences I'm hearing but I'd still like to share some initial impressions.
  
 The genre of music I listen to the most is electronic music, all genres, but I really focused on some melodic dubstep, vocal trance, progressive psy and drum and bass to produce my experiences I'll do my best to describe.
  
 Not to start off on a bad note, but the upon plugging in the UHA760, the first thing that irked me is when the volume is all the way down, it still plays music at low volume.  My UHA-6S.mkII didn't do that, it was dead silent with 0 volume.  _Edit: I realize this is now because of the digital volume compared to the analogue one in the 6S.  The 6S would be silent but as I turned up the volume it first only played out of 1 ear, then engaged in the other after more volume.  The UHA760 plays the volume equally right from the lowest volume setting, which is a very cool feature!_
  
_EDIT: Upon listening further with xfeed, I've come to enjoy this feature more than I initially posted.  See posts #38 - #41_
 How am I enjoying the UHA760? 
	

	
	
		
		

		
			





 
  
 The best way I can describe the differences is the music feels more alive, more engaging.  Instrument separation was more apparent, random noises I would have to listen closely for had it's moment without trying.  The sound stage does seem wider, especially with xfeed on the off position.  As a general statement, the overall presentation of the music sounds more accurate and how the recording was meant to be heard.  I'm assuming this has something to do with the USB upconversion to 192 kHz.  _Edit: Another thing I'm noticing is that vocals sound clearer, crisper and more separate and spacious from the music._
  
 Bass response may seem more accurate, tighter and less sloppy, but I'm having a tough time determining if that's from the improvements in the DAC or the different op-amp.  I miss having a little extra boom but I'm not disappointed by any means.  I remember I noticed a little additional warmth after my UHA-6S.mkII had some time to break in, so I'll monitor that as time goes on.  _Edit: After listening some more, I think what I'm experiencing in addition to tighter more controlled bass, is that the mids and highs I wasn't hearing as much before is what was causing the bass sound slightly more recessed, but in a good way!_
  
 While I'm sure I'll be able to provide more info on this over time, the UHA760 did seem less fatiguing.  My ears are pretty sensitive and I noticed one song on the UHA-6S.mkII got to me and it didn't on the UHA760.  _Edit: Using the xfeed has helped prevent fatiguing even further, another awesome feature!_
  
 I know overall I'll be very pleased with the upgrade to the UHA760 and it'll make my work experience that much more enjoyable.
  
 For anyone interested, the music I used to compare the two units were:
https://soundcloud.com/housemusic/electric-glow-by-tritonal-ft
https://soundcloud.com/seven-lions/royksopp-running-sevenlions-remix
https://soundcloud.com/tritonalmusic/tritonal-now-or-never-pierce
https://soundcloud.com/xthemout/holly-drummond-out-of-my-mind-cto-remix
https://soundcloud.com/adventureclub/lullabies-yuna-adventure-club-remix
https://soundcloud.com/scullious/scullious-meant-to-be-ft-jdr-tiff-lacey
https://soundcloud.com/shogunaudio/optiv-btk-understand-vip
https://soundcloud.com/minnesota/relax-astral-projection-ep
https://soundcloud.com/omnia/bones
 http://youtu.be/IGHxe_QOHgc  - Psy Trance Mix
http://www.youtube.com/watch?v=NH56w5N4SeQ - Live Set
  
_Edit: I should have avoided an initial review after only an hour listening, it's becoming more and more apparent as time goes the benefits of the UHA760.  I'm in shock how beneficial the upconversion is for streaming music.  Nearly every track I've listened to sounds like an upgraded recording.  I'm also finding myself moving to the music more, tapping my foot, drumming a beat, etc._


----------



## musicheaven

geod said:


> My UHA760 arrived in the mail today.  I listened to my UHA-6S.mkII extensively over the past 2 months at work on a daily basis.  The headphones I use to listen are a pair of Brainwavz B2 IEMs.  I listen almost exclusively to streaming music on soundcloud, di.fm and youtube, which was what attracted me to the UHA760.
> 
> Before you read any of this please note that my UHA-6S.mkII has the default AD8610ARZ op-amp, where I chose the OPA209AID op-amp for the UHA760.  I won't know what is the cause of the differences I'm hearing but I'd still like to share some initial impressions.
> 
> ...


. 

Thank you so much for this review, exactly what I was waiting for what makes it even better is your choice of music, exactly as mine. What I like about EDM is the amazing frequency range being used. The ultimate music for gauging electronics from the warm subsonic of dubstep to the high pitch of cymbals, warm pads and synthesizers. I am so amazed about how far electronic based music has gone and the enchanting female vocals on those are pure bliss. By the way your selection will be added to my already vast collection of edm music including some of the authors I already own. Please do come back and give us a second round once you have burned in your amp. This amp is definitively on my buyer's list.


----------



## GeoD

musicheaven said:


> .
> 
> Thank you so much for this review, exactly what I was waiting for what makes it even better is your choice of music, exactly as mine. What I like about EDM is the amazing frequency range being used. The ultimate music for gauging electronics from the warm subsonic of dubstep to the high pitch of cymbals, warm pads and synthesizers. I am so amazed about how far electronic based music has gone and the enchanting female vocals on those are pure bliss. By the way your selection will be added to my already vast collection of edm music including some of the authors I already own. Please do come back and give us a second round once you have burned in your amp. This amp is definitively on my buyer's list.


 
  
 Hi Jon, thanks for the reply.  I'll be happy to post some updates after I get a few weeks burn in and listening done.  Overall, I'm impressed and to me it is worth the extra $100 in cost.  I think this version may struggle with hard to drive headphones, but I'm very pleased with the performance on IEMs.  I'd love to hear what kind of EDM music you're into and use to test your equipment, I always love discovering new artists.  Shoot me a PM with some of your favorites and I will do the same.


----------



## musicheaven

geod said:


> Hi Jon, thanks for the reply.  I'll be happy to post some updates after I get a few weeks burn in and listening done.  Overall, I'm impressed and to me it is worth the extra $100 in cost.  I think this version may struggle with hard to drive headphones, but I'm very pleased with the performance on IEMs.  I'd love to hear what kind of EDM music you're into and use to test your equipment, I always love discovering new artists.  Shoot me a PM with some of your favorites and I will do the same.




Thanks it'll be great. I PM you with an initial list. 

Enjoy!


----------



## castleofargh

geod said:


> Spoiler: Warning: Spoiler!
> 
> 
> 
> ...


 
  
 thank you for the feedback.
 if your ears are sensitive to fatigue, I have some little suggestions.
 -use the crossfeed! if it's well done it will ease the work of you brain trying to understand why some sounds only get into one ear when it's loud and should in natural environment enter the other one too. it's less work for the brain to have some extent of crossfeed. 
 but yes it reduces the wideness of the stage, on the other hand it will add some depth so you don't really lose space (but I get it that some people love super wide sound, a matter of tastes).
 - get rid of the B2 ^_^.  the 10khz spike were killing me for as long as I owned them.
  
 now about the gain, why but holy grail full of guacamole why would you want high gain on the B2?
 I'm done trying to say the with matched volume lower gain is almost always better, nobody would trust the nobody I am when it is so easy to get done in by the "louder is better" effect when switching gains. but here is what Nick (some other dude except he's the one making the amp ^_^) had to say on gain when I spammed him with irrelevant questions a few months back.
  

```
The gain switch on the UHA760 does not change the output impedance. The output impedance is less than 1 ohm for all three gain settings. My approach is to try and keep the output impedance as low as possible to avoid altering the frequency response of IEMs. Using output impedance to create different sounds is an interesting idea, though. I may consider that type of feature for my future designs. Regards, Nick
```
  
  
  
 anyway if the dac part is good, it's all I was hoping for as it is what needed improvement over last version, the amp section was already good enough for me.
 is the volume knob really harder to turn by mistake on the 760? I always feared big knobs in a pocket.


----------



## GeoD

castleofargh - thanks for the reply!
  
 I'm going to try out the crossfeed on low all day today and see how that goes.  I'll be sure to report back.  I guess I didn't understand what it did fully and just assumed it only narrowed the soundstage.  Thank you for the explanation, I would prefer depth over soundstage, so I'm excited to see what comes about.
  
 Also, I appreciate the suggestions on getting rid of the B2's =)  To be honest, for the price I paid for these things ($105) they are amazing.  I'm looking into the 1964-V3 as my next purchase.  If you have any other suggestions within that price range, please let me know ($425+impressions).
  
 It's funny you mentioned the gain, over the course of a day, I ended up switching down to the low gain setting.  It was just always strange for me to have the volume past 12 o'clock, feeling I'm pushing the amp more than I should.  I like to set the volume to the lowest volume setting where I can begin to hear the bass I want.  It was always just easier to use high gain and use a lower volume setting.  
  
 Just to confirm, you're offering the suggestion that the lowest gain with a higher volume setting is going to perform better than a higher gain with a lower volume setting assuming they are at equal volume levels.
  
 The DAC part is great to my ears, a step up from the UHA-6S.mkII ... I would think that the volume knob is harder to turn by mistake on the 760 compared to the 6S.II , the knob is smaller for one thing and due to the smaller size, requires slightly more effort to turn.  
  
 Thanks a bunch for your suggestions, they are greatly appreciated!
  
 George


----------



## castleofargh

crossfeed is not an easy thing to get right for a number of reasons, so it might be nice for you, or not. that's why I was interested in this amp in the first place.
  
 can't advise you much for an IEM, they're all so different. I only heard one 1964 it was the quad I believe (not even sure about that). and there was a lot of bass ^_^.  but going custom in those prices is a great thing. when it's well done comfort is really superior.
  
  
  
 about gain: usually using the lowest gain that still gives you enough volume is the way to get the best out of an amp.
 with high gain and low value on the volume knob, you boost the voltage a lot more than you need for your IEM, then reduce all that excess volume with the knob (knob volume maxed out= no reduction of the amplified signal). it might just bring troubles like noise, distortion, or clipping, but it will not bring more power. gain plays with voltage(how loud it is) not power.


----------



## GeoD

castleofargh said:


> crossfeed is not an easy thing to get right for a number of reasons, so it might be nice for you, or not. that's why I was interested in this amp in the first place.
> 
> can't advise you much for an IEM, they're all so different. I only heard one 1964 it was the quad I believe (not even sure about that). and there was a lot of bass ^_^.  but going custom in those prices is a great thing. when it's well done comfort is really superior.
> 
> ...


 
 Thank you castleofargh, for your insight.  I spent most of today listening to the 760 with xfeed on and I can honestly say I'm not missing as much soundstage as I originally thought.  I also have noticed it is less fatiguing and have experienced a little more depth as you mentioned.  It's comical how fast I rushed into publishing my impressions without even understanding the purpose and benefits of the amp.
  
 I have also been listening on low gain all day and it has been great.  I recall the days of when I had custom car stereo's installed, I'd also set the volume to the max and adjust the amp to my peak listening volume so I'd have the entire volume range to work with.  Using the lowest gain on the 760 (-12 db) I would still never crank it up 100%, so there it will remain.  In fact even on the lowest gain, I cannot see venturing much more than 12 o'clock, leaving me with plenty of power and I know my ears will thank me for that insight with additional years of enjoyment.  Thank you!
  
 Was the bass overwhelming on the 1964?  Were the mids and highs recessed because of that at all?  The extra bass is actually what is attracting me to the 1964s, but wouldn't want that unless the mids and highs were still presented properly.  Thanks again for everything, you've been very helpful.


----------



## lee730

castleofargh said:


> thank you for the feedback.
> if your ears are sensitive to fatigue, I have some little suggestions.
> -use the crossfeed! if it's well done it will ease the work of you brain trying to understand why some sounds only get into one ear when it's loud and should in natural environment enter the other one too. it's less work for the brain to have some extent of crossfeed.
> but yes it reduces the wideness of the stage, on the other hand it will add some depth so you don't really lose space (but I get it that some people love super wide sound, a matter of tastes).
> ...


 
  
 To be honest as of now I am nt noticing the crossfeed providing any benefit or negative for me on my AK120 S mod. Seems to not even alter the soudn at all. Will have to use it more to see if this is still the case... Like I usually notice the left and right pan to be more centered but not in this case...


----------



## shotgunshane

I thought I'd post this here from the Herus thread:



shotgunshane said:


> Some very brief Herus and UHA760 thoughts (the 760 is brand new and I've only got a couple of hours with it) using an iPhone 5>CCK>USB>DAC/amp:
> 
> The Herus sounds more dynamic and bigger in size than the 760, with a little bit better deep bass.
> The 760 sounds more laid back and smoother to me; doesn't quite have the sparkle of the Herus.
> ...




***760 with ad 4627brz opamp


----------



## bearFNF

Just ordered mine last night...


----------



## cooperpwc

shotgunshane said:


> I thought I'd post this here from the Herus thread:





> shotgunshane said:
> 
> 
> > Some very brief Herus and UHA760 thoughts (the 760 is brand new and I've only got a couple of hours with it) using an iPhone 5>CCK>USB>DAC/amp:
> ...





> ***760 with ad 4627brz opamp


 
  
 Great post within a post.


----------



## lee730

cooperpwc said:


> Great post within a post.


 
  
 Would you be interested in buying my 760 off me lol .


----------



## cooperpwc

lee730 said:


> Would you be interested in buying my 760 off me lol .


 
  
    Kind of but I'm a bit rich on the portable amp side right now and I also have an expensive home amp (GS-X mk2) coming down the pipe. The 760 is an indulgence that I will have to pass on for now.


----------



## Shini44

i am between this one and pico slim, the slim got better treble and mids compared with uha6mkii, also does last longer per charge, uha is warmer though, i wish someone who had the pico go and test the uha760 for us


----------



## shotgunshane

I thought the pico slim was on the bright side. It was a good match with the Tera player. I did not like it with iPods and the iPhone. 

The 760 seems neutral to me. Neither bass tilted, like the Quickstep and neither treble tilted, like the pico slim. The 760 is also laid back to me. It is not an aggressive amp like the the O2.


----------



## Shini44

seems like i will go with the Pico Slim, the Uha6mkii was one of the best amps i had, and the 760 take this line to another level but sadly it won't give me what i need, i am crazy enough to buy the 760 to add it to my collection  nothing reward a good product that you respect a lot better than buying it :3 will lend it to my friends etc.


----------



## shotgunshane

Yeah if you really like the treble of the slim, the 760 is not going to give you that, at least with the 4627brz opamps.


----------



## Shini44

lee730 said:


> Would you be interested in buying my 760 off me lol .


 
 i wonder how long will it last XD why did you order it? you sold the older version which didn't last this long after you decided that the Triad was better than it  or going to toy around with it to see how better it is then sell it?  i think you will do so as usual hehe


----------



## lee730

shini44 said:


> i wonder how long will it last XD why did you order it? you sold the older version which didn't last this long after you decided that the Triad was better than it  or going to toy around with it to see how better it is then sell it?  i think you will do so as usual hehe


 
  
 I wanted the better volume control, the multi gain and crossfeed features. But ultimately I wanted better audio quality than my T1 amp which I don't feel I get from the 760. It is a more aggressive and upfront amp overall. It gets fatiguing on my AK120-S mod. I'm using the stock Op-amp Nick includes. The amp is intimate and has good depth to its sound. I consider it on the neutral side.


----------



## lin0003

I'll be getting these in for review soon and perhaps arrange a tour if Nick permits it...


----------



## cooperpwc

I am curious as to how the 760's USB DAC + amp combo sounds. My DX50 + Pico Power which is exquisite with the Heaven VI is a bit bright with the Kaede. The brightness issue is in the DX50 not the Pico Power. 
  
 (I do not think that the DX50 line out is generally too bright. Actually the Kaede is quite bright but sounds great with USB Monica - NOS Philips TDA1545 - as a source. It is a synergy issue.)
  
 The 760 could be an interesting all-in-one to listen to the Kaede from my laptop on the road. Highly theoretical but if anyone has a comment on the sound signature of the DAC + amp combo, it would be appreciated.


----------



## musicheaven

cooperpwc said:


> I am curious as to how the 760's USB DAC + amp combo sounds. My DX50 + Pico Power which is exquisite with the Heaven VI is a bit bright with the Kaede. The brightness issue is in the DX50 not the Pico Power.
> 
> (I do not think that the DX50 line out is generally too bright. Actually the Kaede is quite bright but sounds great with USB Monica - NOS Philips TDA1545 - as a source. It is a synergy issue.)
> 
> The 760 could be an interesting all-in-one to listen to the Kaede from my laptop on the road. Highly theoretical but if anyone has a comment on the sound signature of the DAC + amp combo, it would be appreciated.




I also got my eyes on the 760 but the yet to be released coax in version, I like to be able to use it as a transport with the DX50.


----------



## castleofargh

lin0003 said:


> I'll be getting these in for review soon and perhaps arrange a tour if Nick permits it...


 

 same here, but when I asked if I could send it to some fellow reviewers he told me he didn't have enough demo at the moment to let me/us keep it for an extended time. my guess is that he already has his own tour fully booked.
  
 anyway people expect feedbacks coming soon.


----------



## Bazirker

I'm very interested to hear a comparison between the 760 and the 6S which have the same op amps. I really enjoy my 6S and want to know if the upgrade might be worth it...


----------



## castleofargh

```
The amp section in the UHA760 is basically the same as the UHA-6S.MKII.
```
 from Nick 2months ago.
  
  
  
 in my opinion you should upgrade if you have a real use of the dac. the 192khz upsampling should be a nice jitter killer.
 or if you want some crossfeed. usually the older the album the more I find a need for crossfeed, but it's not good for all musics so the different settings are nice.
  for the volume knob being less subject to accidental changes (smaller).
 or for the digital volume and 3gain positions. for IEMs specially this is a life changer for ease of use and ridding yourself of channel imbalance troubles. since I've had the pico slim (my first digitally controlled volume amp), I can't see myself going back to analog volume, even on my RSA there was really no imbalance trouble and the knob was great, but it was just not as convenient.
  

 well here are my reasons ^_^ if it was 100% the amp section that concerned me I would get the 6S and buy pringles with the difference.


----------



## FlySweep

I've had the 760 for almost two weeks now.. my 760 has the ADA4627-BRZ opamps.  In the past, I've owned two 6S MKII's (one w/ the OPA209.. and another w/ ADA4627-ARZ).  I much preferred the 4627 to the 209 in the 6S MKII.. so much so that when it came time to purchase another amp (the wonderful Neco Soundlab V4), I had the ADA4627 installed in it as well.. just so you know where my preferences lay.  I may be getting a 6S on loan.. but going off memory (so take this with a grain of salt), the 760's DAC section seems to sound virtually the same as the 6S MKII's DAC section.  Again, I'm going totally off memory.. but having spent a lot of time with the 6S, I don't seem to sense any large difference (either positive or negative) vs the 6S's DAC.  Generally speaking, I found the 6S (and 760's) DAC section quite serviceable.. not the last word in resolution.. but in terms of having a bundled DAC with an amp section that's the 'star of the show,' the DAC held up quite well.  I did find the 760 noticeably scales up with a better DAC (in my case, I tossed the Vio V800 at it).
  
 Moving onto the amp sections (comparing the 6S' 4627A vs the 760's 4627B).. again, the 760's amp section seems very similar to the 6S'.  My 760's amp section (w/ the 4627B) seems a little transparent.. perhaps a little more refined.. and more dynamic than how I remember the 6S' 4627A sounding.. but being that these two opamps are very similar, I wouldn't expect much difference.  From what I understand, the BRZ's datasheet indicates slightly better specs than the ARZ.
  
 General sonic impressions?  Like the 6S, the 760 is a wonderful amp.  Very very transparent, fast, dynamic, and tonally accurate.  _Frighteningly_ silent background.. terrific control, and smooth dynamics.  I use the 760 almost exclusively with the UERM & JH13Pro.. the combo sounds nothing short of phenomenal.  I'll echo @shotgunshane's opinion that it pairs exceptionally well with the JH13.. but the UERM/760 pairing was eye-popping for me.  I've had the UERM & JH13Pro for some time and I can't choose a favorite between them.  They're both considered neutral phones, but also tend to compliment each other perfectly (the UERM being neutral to slightly bright.. while the JH13 leans to the warm side of neutral).
  
 Running both through the paces with the 760, the UERM has revealed itself to be my favorite IEM to date.  The JH13 certainly isn't going anywhere.. in some areas, it's more technically capable than the UERM.. but IME, the UERM with the 760 (ADA4627-BRZ) & a HQ, dedicated DAC makes for one of the most compelling listens in all of audio.  Back to the 760.. I think it offers a ton of sound for the price I paid ($379).  While the SQ of the amp section is marginally better than the 6S MKII (a near perfect portable amp as it is, IMO).. the digital pot (especially if you use IEMs), three gain levels (again, especially if you use IEMs), and crossfeed make the 760's $100 premium more than worth it for me.


----------



## castleofargh

thank you for this feedback, pretty much what I'm expecting and that's a good thing.


----------



## Bazirker

Fantastic impressions, FlySweep.  Thanks!


----------



## kimvictor

So the amp section is same for both mk.ii and 760. I guess I'll hold on to my mk.ii. I do need an optical input after all.


----------



## Shini44

kimvictor said:


> So the amp section is same for both mk.ii and 760. I guess I'll hold on to my mk.ii. I do need an optical input after all.


 
 in that case i should go for MKII with lower gain, will ask them to lower it to be good for a CIEM, yet how many DBs lower? -12?


----------



## kimvictor

shini44 said:


> in that case i should go for MKII with lower gain, will ask them to lower it to be good for a CIEM, yet how many DBs lower? -12?


idk. Ask Nick. He knows what he's doing.


----------



## thegunner100

shini44 said:


> in that case i should go for MKII with lower gain, will ask them to lower it to be good for a CIEM, yet how many DBs lower? -12?


 

 Depends what IEMs you're using, and the line-out output of your DAC/DAP. -12dB is a safe point for most CIEMs but may be a little bit low for full sized headphones with a lower voltage source. And of course if your source has a volume control without any SQ loss, then even better.


----------



## Shini44

thegunner100 said:


> Depends what IEMs you're using, and the line-out output of your DAC/DAP. -12dB is a safe point for most CIEMs but may be a little bit low for full sized headphones with a lower voltage source. And of course if your source has a volume control without any SQ loss, then even better.


 
 planing to use it CIEMs wise only so -12 db it is  got the M-Stage amp so its good for full size cans yet very bad control for the 1ohm CIEMs


----------



## castleofargh

it really depends on the source.
 just take your M-stage and make a few mp3s with a gain to simulate a few values.


----------



## H20Fidelity

Thanks to a fellow Head-fier and Leckerton, I've had this dac/amp on demo for almost a week so far.

 To be honest guys, I'm not really feeling the magic with this amp, I've been running it from IHIFI 760 line out and the dac section from my laptop. it has some good aspects, such as tight refinement, soundstage width, a nice amount of control and it does improve over the headphone out, it does clean up the signal and improve areas, certainly sounds more professional although I'm not really a fan of how far you need to turn the volume pot to get sufficient volume levels from this little thing. I need to have the pot at about 60% for normal listening levels with 10ohm and 32ohm IEM using the middle gain setting. Don't get me wrong it's a decent amp I just don't feel any vibe from it personally compared to some other cheaper offerings by JDS Labs.

 I'll have the amp for another week and keep playing with it. I've tried the DAC section from my laptop and again, I'm just not being swept away as a $439 product should suggest, there might be some synergy issues with my gear because I've spoken to others who own the amp (they're now selling it) though they said they found it rather capable but again decided something at half the price was their preference, I think it was Tralucent T1 they liked more? So that's where I am, while I think UHA760 is enjoyable and the build is nice (it's rather heavy too btw) I haven't had any thoughts I need this dac/amp in my life, not when I have been juggling with JDS C5 and C421 this past week.


----------



## lin0003

h20fidelity said:


> Thanks to a fellow Head-fier and Leckerton, I've had this dac/amp on demo for almost a week so far.
> 
> To be honest guys, I'm not really feeling the magic with this amp, I've been running it from IHIFI 760 line out and the dac section from my laptop. it has some good aspects, such as tight refinement, soundstage width, a nice amount of control and it does improve over the headphone out, it does clean up the signal and improve areas, certainly sounds more professional although I'm not really a fan of how far you need to turn the volume pot to get sufficient volume levels from this little thing. I need to have the pot at about 60% for normal listening levels with 10ohm and 32ohm IEM using the middle gain setting. Don't get me wrong it's a decent amp I just don't feel any vibe from it personally compared to some other cheaper offerings by JDS Labs.
> 
> I'll have the amp for another week and keep playing with it. I've tried the DAC section from my laptop and again, I'm just not being swept away as a $439 product should suggest, there might be some synergy issues with my gear because I've spoken to others who own the amp (they're now selling it) though they said they found it rather capable but again decided something at half the price was their preference, I think it was Tralucent T1 they liked more? So that's where I am, while I think UHA760 is enjoyable and the build is nice (it's rather heavy too btw) I haven't had any thoughts I need this dac/amp in my life, not when I have been juggling with JDS C5 and C421 this past week.


 
 Interesting... I guess I'll see when I listen to it I guess.


----------



## desmoface

h20fidelity said:


> I have been juggling with JDS C5 and C421 this past week.




Is it safe to assume you prefer the c5 to the UHA760? Thanks for the post.

Steve


----------



## H20Fidelity

lin0003 said:


> Interesting... I guess I'll see when I listen to it I guess.




See what you think.  




desmoface said:


> Is it safe to assume you prefer the c5 to the UHA760? Thanks for the post.
> 
> Steve




From a value for money perspective, yes quite easily. However taking the price away the Leckerton does have darker background and offer more refinement, it also has the most width to the soundstage. We need to remember that UHA760 has the added dac section which adds up the cost. 

I had these 5 amps this week, I ended up choosing C421 (OP2227) as my new amp from the bunch.


----------



## castleofargh

h20fidelity said:


> Thanks to a fellow Head-fier and Leckerton, I've had this dac/amp on demo for almost a week so far.
> 
> To be honest guys, I'm not really feeling the magic with this amp, I've been running it from IHIFI 760 line out and the dac section from my laptop. it has some good aspects, such as tight refinement, soundstage width, a nice amount of control and it does improve over the headphone out, it does clean up the signal and improve areas, certainly sounds more professional although I'm not really a fan of how far you need to turn the volume pot to get sufficient volume levels from this little thing. I need to have the pot at about 60% for normal listening levels with 10ohm and 32ohm IEM using the middle gain setting. Don't get me wrong it's a decent amp I just don't feel any vibe from it personally compared to some other cheaper offerings by JDS Labs.
> 
> I'll have the amp for another week and keep playing with it. I've tried the DAC section from my laptop and again, I'm just not being swept away as a $439 product should suggest, there might be some synergy issues with my gear because I've spoken to others who own the amp (they're now selling it) though they said they found it rather capable but again decided something at half the price was their preference, I think it was Tralucent T1 they liked more? So that's where I am, while I think UHA760 is enjoyable and the build is nice (it's rather heavy too btw) I haven't had any thoughts I need this dac/amp in my life, not when I have been juggling with JDS C5 and C421 this past week.


 
  
 I find the sound to be mighty clean. and as you might know I struggle with hiss and other noises all the time because I listen mostly at very low volumes. my 334 alone makes this amp a great value, if you ever had any trouble with hiss, it doesn't know what hiss means. most amps do a good job at lowering noise levels, but this one really is noise free from tip to toe.
 but I guess the sound can be almost too transparent to really feel the benefits of adding the amp.
  
 also I won't make solid statement as soon after having it (didn't try test tones yet), but it doesn't have the sub bass presence of some other amps. I feel like there might be a slight roll off in the sub bass (and sub bass only, bass is super tight and very well controlled). it would explain why I love the bass of my 334 so much on it. but with say ... er4  I guess a little bass boost wouldn't be a bad thing.
  
 also what displeases you with the volume control is what I like about it ^_^. in the end it goes loud enough for anything I own (mid gain is ok for my hd650 to sound loud), and I believe as far as sound technicalities go, that it is better to get the op amp to a certain level and then use the less possible volume reduction, instead of having a power house and then need to use the knob to reduce volume to a minimum.
 ofc you need to have a loud enough sound in the end, but any phone I consider portable will be driven loud enough, the hd650 is already an extra in the portable universe. so other amps extra volume is just for show when it comes to my usage. I never ever had to go above low gain on a RSA amp and even then I don't think I ever passed 12 o'clock. that's great if you need that extra volume for some phones, but else ...
 if I ever buy an orthodynamic, I will also buy a dedicated amp that will most likely be of very poor practical use as portable gear with my IEMs. I don't believe in the all in one wonder amp.
  
 now between this one and the UHA6 I really wouldn't know as I have little use of the integrated dac so maybe saving money is a good idea? on the other hand I do use the crossfeed and I don't know how lee couldn't tell the difference. maybe it's because of the kind of music he's listening or the phones he used? I really don't know, but the crossfeed works just as intended, first level is subtle and 2nd level is what I'm used to have (smaller soundstage but brought slightly in front of me as if I went from 180degree sound to ... let's say 130 (I don't really know what 10degrees look like so don't take the value too seriously plz ^_^). anyway when you have use for crossfeed you will use this one (the more you listen to speakers the more corssfeed should appeal to you).
  
 all in all I find it to be a great option for IEM users. as in, no noise, volume control, channel balance, neutral signature, low impedance.
 the sound is something you will like or not, that's not for me to decide but I didn't ear any noticeable weakness except maybe the discrete sub bass section. more on this when I have really looked into it, that's a first impression only.


----------



## lin0003

Got this a few days ago and truth be told I'm a little disappointed with this amp. I mean I've read wonderful things about the 6S and supposedly this is almost the same but like H20 I'm just not feeling the magic. I tried the DAC and it's decent, but falls short of the one on my DX50. For some reason I feel like this is a little warm while other people have been saying that it is neutral. It is quite good everywhere especially with the background noise. Like others have mentioned it's completely silent. It has good imaging ans separation but I just don't find it a much better than something like a T1. 
  
 Also it isn't loud enough. It was too soft for my IEMs on low gain and I listen pretty softly (I think). Build is good and the design is nice as well. 
  
 I wanted to like it, I really did, but unfortunately I don't find it necessarily better than amps in the $200 range. This would be competitive at $250-300 but I just can't recommend it at  $439. Sorry Nick, but maybe this is just not for me.


----------



## eyal1983

Guys
 on my 6smk2 i replaced the OPAMPs
 but on this unit, the OPAMPs are soldiered !


----------



## bearFNF

eyal1983 said:


> Guys
> on my 6smk2 i replaced the OPAMPs
> but on this unit, the OPAMPs are soldiered !



Correct, they are.


----------



## Fungus

flysweep said:


> I've had the 760 for almost two weeks now.. my 760 has the ADA4627-BRZ opamps.  In the past, I've owned two 6S MKII's (one w/ the OPA209.. and another w/ ADA4627-ARZ).  I much preferred the 4627 to the 209 in the 6S MKII.. so much so that when it came time to purchase another amp (the wonderful Neco Soundlab V4), I had the ADA4627 installed in it as well.. just so you know where my preferences lay.  I may be getting a 6S on loan.. but going off memory (so take this with a grain of salt), the 760's DAC section seems to sound virtually the same as the 6S MKII's DAC section.  Again, I'm going totally off memory.. but having spent a lot of time with the 6S, I don't seem to sense any large difference (either positive or negative) vs the 6S's DAC.  Generally speaking, I found the 6S (and 760's) DAC section quite serviceable.. not the last word in resolution.. but in terms of having a bundled DAC with an amp section that's the 'star of the show,' the DAC held up quite well.  I did find the 760 noticeably scales up with a better DAC (in my case, I tossed the Vio V800 at it).
> 
> Moving onto the amp sections (comparing the 6S' 4627A vs the 760's 4627B).. again, the 760's amp section seems very similar to the 6S'.  My 760's amp section (w/ the 4627B) seems a little transparent.. perhaps a little more refined.. and more dynamic than how I remember the 6S' 4627A sounding.. but being that these two opamps are very similar, I wouldn't expect much difference.  From what I understand, the BRZ's datasheet indicates slightly better specs than the ARZ.
> 
> ...


 
 Do you hear any background hiss on all 3 gain setting with the volume turned all the way up to max and with no music playing on your JH13s?


----------



## SDBiotek

Even if you do get some hiss with no music playing, why should it matter? Hiss is only a problem if you can hear it when actually listening to music. I get some hiss with my Centrance HiFi M8 when using iems, but it isn't noticeable while music is playing. The M8 is optimized for powering full size headphones, though, so the gain is higher and is expected. My 6s MkII has a black background with all of my iems.


----------



## Fungus

sdbiotek said:


> Even if you do get some hiss with no music playing, why should it matter? Hiss is only a problem if you can hear it when actually listening to music. I get some hiss with my Centrance HiFi M8 when using iems, but it isn't noticeable while music is playing. The M8 is optimized for powering full size headphones, though, so the gain is higher and is expected. My 6s MkII has a black background with all of my iems.


 
 It matters because a lot of music I listen to involves some quiet passages. I would of expected the HIfI M8 to be hiss free like the dacport.


----------



## lee730

I can hear a very slight hiss on the high gain. On low gain it is completely black. With medium gain its pretty much black as well.


----------



## Fungus

lee730 said:


> I can hear a very slight hiss on the high gain. On low gain it is completely black. With medium gain its pretty much black as well.


 
 Thanks. So on high gain, does the hiss increases as you turn the volume up or stay at a constant level.


----------



## SDBiotek

fungus said:


> Thanks. So on high gain, does the hiss increases as you turn the volume up or stay at a constant level.



Just a guess on my part, but I can't imagine anyone needing to use high gain to power iems. My Noble K10s have a black background on my 6S MkII on low gain, whose amp section is similar to that on the UHA 760. The low gain setting on the UHA 760 was probably designed with iems in mind. I do not think hiss will be an issue with any iem and the 760, but contact Nick at the Leckerton website and ask him directly if you need additional assurance.


----------



## lee730

fungus said:


> Thanks. So on high gain, does the hiss increases as you turn the volume up or stay at a constant level.


 
  
 It stays the same from what I can tell. But you'd go def way before that would become an issues anyways. I get to about a quarter volume on high gain at most on my IEMs.
  
 Mine is also up for grabs if you like .


----------



## Fungus

lee730 said:


> It stays the same from what I can tell. But you'd go def way before that would become an issues anyways. I get to about a quarter volume on high gain at most on my IEMs.
> 
> Mine is also up for grabs if you like .


 
 Interested. So how much are you looking for? Please send me a pm.


----------



## castleofargh

I dare you to find someone complaining about hiss on this amp. impossibru!!!!!!!!! cleaner would mean removing part of the music itself. and I'm a guy whining on noises others don't seem to hear(dx50, f886, ...).


----------



## Uchiya

Woooow, the 760 is a nice match with my re-272's.  Very nice soundstage all around, and also deep.  The 6s mk.2 was a little dry for me but I'm liking what I'm hearing from the 760.  Wish it had longer battery life though.  I'd pay something extra to be able to have this in a bigger case with a large battery.  Source is LG G2, usb out.


----------



## lee730

Glad you like it! Don't forget to leave me feedback and I'll do the same for you .


----------



## headwhacker

uchiya said:


> Woooow, the 760 is a nice match with my re-272's.  Very nice soundstage all around, and also deep.  The 6s mk.2 was a little dry for me but I'm liking what I'm hearing from the 760.  Wish it had longer battery life though.  I'd pay something extra to be able to have this in a bigger case with a large battery.  Source is LG G2, usb out.


 
  
 You must be comparing 2 different opamps. 760 and 6S share the same amp design.


----------



## lee730

headwhacker said:


> You must be comparing 2 different opamps. 760 and 6S share the same amp design.


 
  
 There is differences in the design overall though including the power supply. He improved upon that on the 760. Cleaner soound, lower noise floor to my knowledge. Read the specs on his site.


----------



## Uchiya

lee730 said:


> There is differences in the design overall though including the power supply. He improved upon that on the 760. Cleaner soound, lower noise floor to my knowledge. Read the specs on his site.


 
 This.


----------



## headwhacker

lee730 said:


> There is differences in the design overall though including the power supply. He improved upon that on the 760. Cleaner soound, lower noise floor to my knowledge. Read the specs on his site.


 
  
 Sure yeah it's improved. Power supply/regulation, additional crossfeed, digital volume control and 3 step gain settings, but the overall design of the amp section is similar. I asked him the same question and other than the improved/added features everything else is similar.
  
 Besides, how can you hear a "cleaner" sound when it's already clean? I was thinking the difference must have come from listening with 2 different opamps. But then hearing differences is a matter of subjective opinion.


----------



## lee730

headwhacker said:


> Besides, how can you hear a "cleaner" sound when it's already clean? I was thinking the difference must have come from listening with 2 different opamps. But then hearing differences is a matter of subjective opinion.


 
  
 There is a difference with a lower noise floor and cleaner power to the source. The Fiio X5 is a really good example of this and it shows through with its crazy micro-detailing & low noise floor. If you cannot hear that or haven't experienced that then there really is no point in dragging this on with you. Connecting my Triad L3 to its power supply vs the batteries is a huge difference (blacker background, more dynamic, bigger sound staging, improved separation/imaging, deeper bass. The better your sources & headphones/IEMs are, the more apparent those differences will be (IMO).


----------



## Brendanz

What attracted me to buy this at first was the cross feed functionality and base on the fact that the UHA 6s Mk2 was well received. I received my UHA760 on Christmas Eve last year .... After a few months of listening to it feel that for the price tag it should have been much better (OPA627). I paired it with AK120 and 1964 ears quads with the gain on low with high cross feed. The crossfeed does help a bit but not greatly with the channel inbalance in IEMs or whatever you call it . When paired with my Audeze Lcd 2.2 on high gain I would require the volume knob to be at around 3'o clock when listening to rock or blues . When listening to some classical pieces I would have to crank the volume up to almost max volume. I feel that the power could have been better but that might compromise the extremely low noise floor which I absolutely love.


----------



## Uchiya

I like the RE-272's with Meier house sound.  Was going to sell the 760 until I tried them with my Blox M2c's.  I really like what I was hearing.  Have to keep it now.  Source is USB out from Surface 2.  Sweetness.


----------



## castleofargh

I posted a long, non informative, hard to read review on the 760(needless say, in a poor english). viewer discretion's advised. if you feel adventurous, or if you really have nothing better to do, go read it:
 http://www.head-fi.org/products/leckerton-audio-uha760/reviews/10732


----------



## Kendoji

Haha great review, and good read.


----------



## namaiki

I'm really liking the UHA760 at the moment. Great dynamics, great soundstage/separation (I have crossfeed set to 'bypass') and immersion (much better than the other portable DAC/amp combos that I have previously owned) and pleasurable bass rumble on my headphones that are capable of it - and I'm only using the inbuilt DAC.


----------



## gixxerwimp

After reading about 3G/4G/Wi-Fi interference with the UHA760, I sent Nick an email asking which op-amp option would have the best EMI properties. Before he had a chance to answer, I found this blog entry, which would seem to answer the question. I'll update if he gives me a more detailed reply.
  
http://www.leckertonaudio.com/blog/2012/11/choosing-output-op-amps


> The AD8610 is currently the best choice for most customers. It measures very well electrically, it has low susceptibility to interference, and it has a proven record in the world of portable hi-fi.


----------



## gixxerwimp

Nick's reply.


> Leckerton Audio <nick@leckertonaudio.com> wrote:
> 
> 
> > Hi Jack,
> ...


 
  
 I've asked him if he has any recommendations on OTG cables for use with Android phones.


----------



## Bazirker

My old UHA-6SmkII with the 8610 had virtually no noise from EMI out of my Galaxy S5 via USB OTG.  Same goes for my UHA760.


----------



## gixxerwimp

bazirker said:


> My old UHA-6SmkII with the 8610 had virtually no noise from EMI out of my Galaxy S5 via USB OTG.  Same goes for my UHA760.




Do you also have the 8610 in your 760? 

Any differences in SQ between the 6SmkII and 760? Why did you upgrade to the 760?

What kind of battery life have you seen running them as DAC/amps?


----------



## gixxerwimp

*gixxerwimp* /img/forum/go_quote.gif 





> I've asked him if he has any recommendations on OTG cables for use with Android phones.


 
  
 Nick's reply:


> I don't have any specific OTG USB cable recommendations, but generally the shorter, the better. Some OTG cables are more like adapters with a micro B plug and a standard A socket on the other – they're meant to connect to a cable with micro B and standard A plugs, but this means you end up with two cables and perhaps some unnecessary length. There are some short micro B to micro B cables around, although they don't seem that common. I've been told this cable works with Android, although I haven't tried it myself:
> 
> https://hakshop.myshopify.com/products/micro-to-micro-otg?variant=211796287
> 
> Regards, Nick


----------



## Bazirker

gixxerwimp said:


> Do you also have the 8610 in your 760?
> 
> Any differences in SQ between the 6SmkII and 760? Why did you upgrade to the 760?
> 
> What kind of battery life have you seen running them as DAC/amps?




No, I don't. (See signature for op amp) I like the 760 better, but it's mostly because of the lower gain setting being nicer with my sensitive customs. Honestly, I don't think there's much difference between the 760 and the 6SmkII, and I wouldn't have gotten/kept the 760 if it weren't for the excellent deal I got on a used 760. The battery life is better in the 6SmkII. I don't use it as an amp, but the DAC gets 10 hours or less of battery life. It's not the best, but I can make it through a day without any trouble.


----------



## gixxerwimp

bazirker said:


> No, I don't. (See signature for op amp) I like the 760 better, but it's mostly because of the lower gain setting being nicer with my sensitive customs. Honestly, I don't think there's much difference between the 760 and the 6SmkII, and I wouldn't have gotten/kept the 760 if it weren't for the excellent deal I got on a used 760. The battery life is better in the 6SmkII. I don't use it as an amp, but the DAC gets 10 hours or less of battery life. It's not the best, but I can make it through a day without any trouble.



Sorry, didn't see your sig on the mobile site. 

If your not using it as an amp, how does low gain make a difference? Or do you still have the 6SmkII and use it as a DAC only (but there's no line out?) and the 760 as a DAC/amp? 

Do you find crossfeed a useful feature?


----------



## Bazirker

gixxerwimp said:


> Sorry, didn't see your sig on the mobile site.
> 
> If your not using it as an amp, how does low gain make a difference? Or do you still have the 6SmkII and use it as a DAC only (but there's no line out?) and the 760 as a DAC/amp?
> 
> Do you find crossfeed a useful feature?




Low gain matters because it basically detirmines the sensitivity and resolution of the volume control. You reduce the maximum volume in exchange for finer tuning of the volume. When you're using headphones like customs or most IEM's that have a low impedance, you want to use a low gain setting while high impedance headphones will want a high gain setting. 

I don't still have my mkII. I used both it and my current 760 as a DAC/amp; I don't think I ever used the analog input once. The behavior of the device is identical regardless of input. There isn't a "line out" on either device; there's one output, and it's for your headphones. I think it would be an odd setup to use this headphones output as a line out for use in yet another amp, but to each his own, I guess.

I don't use crossfeed, but some people swear by it. For what it's worth, it does work well on the 760.


----------



## gixxerwimp

bazirker said:


> Low gain matters because it basically detirmines the sensitivity and resolution of the volume control. You reduce the maximum volume in exchange for finer tuning of the volume. When you're using headphones like customs or most IEM's that have a low impedance, you want to use a low gain setting while high impedance headphones will want a high gain setting.
> 
> I don't still have my mkII. I used both it and my current 760 as a DAC/amp; I don't think I ever used the analog input once. The behavior of the device is identical regardless of input. There isn't a "line out" on either device; there's one output, and it's for your headphones. I think it would be an odd setup to use this headphones output as a line out for use in yet another amp, but to each his own, I guess.
> 
> I don't use crossfeed, but some people swear by it. For what it's worth, it does work well on the 760.




Thanks for the clarification. I was confused when you said "I don't use it as an amp". I guess you meant "amp only".

I understand the need for adjustable gain and that the 760 has -12db / 0db / +12db (I think).

Now that the HA-2 is finally out, I'd love to get a direct comparison of the two.


----------



## Bazirker

gixxerwimp said:


> Thanks for the clarification. I was confused when you said "I don't use it as an amp". I guess you meant "amp only".
> 
> I understand the need for adjustable gain and that the 760 has -12db / 0db / +12db (I think).
> 
> Now that the HA-2 is finally out, I'd love to get a direct comparison of the two.


 
  
 I meant I use it as a DAC/amp, where I use the USB input.  I never use it just as an amp, where the analog input would be used.
  
 What's the HA-2?


----------



## gixxerwimp

> *Bazirker* /img/forum/go_quote.gif
> What's the HA-2?


 
  
 http://www.head-fi.org/t/737787/oppo-to-reveal-pm-3-planar-magnetic-headphones-and-ha-2-portable-headphone-amplifier-at-rmaf
  
 http://www.head-fi.org/t/755879/oppo-ha-2-portable-headphone-amplifier-dac-discussion-thread


----------



## Bazirker

gixxerwimp said:


> http://www.head-fi.org/t/737787/oppo-to-reveal-pm-3-planar-magnetic-headphones-and-ha-2-portable-headphone-amplifier-at-rmaf
> 
> http://www.head-fi.org/t/755879/oppo-ha-2-portable-headphone-amplifier-dac-discussion-thread


 
  
 Oooooooh, that looks pretty awesome.  Yeah, I'd love to hear them both next to one another.


----------



## gixxerwimp

bazirker said:


> gixxerwimp said:
> 
> 
> > http://www.head-fi.org/t/737787/oppo-to-reveal-pm-3-planar-magnetic-headphones-and-ha-2-portable-headphone-amplifier-at-rmaf
> ...


 
  
 If you have an OPPO dealer nearby, maybe you can take your UHA760 there for a shootout!


----------



## diamondears

Anybody has used/tried/heard the PSB M4U1 or NAD HP50 with the Leckerton UHA-760 (or UHA-6S MkII)? And has compared it with the iFi nano or micro iDSD + O2? I'm "itching" for a better portable. 

Wondering if there's any, and whether the Leckerton has ateast equally good sound but different house sound signature?


----------



## castleofargh

diamondears said:


> Anybody has used/tried/heard the PSB M4U1 or NAD HP50 with the Leckerton UHA-760 (or UHA-6S MkII)? And has compared it with the iFi nano or micro iDSD + O2? I'm "itching" for a better portable.
> 
> Wondering if there's any, and whether the Leckerton has ateast equally good sound but different house sound signature?


 

 o2 is transparent, leckerton is transparent. so different house sound is going to be a problem. I only know of one transparent.


----------



## uchihaitachi

castleofargh said:


> o2 is transparent, leckerton is transparent. so different house sound is going to be a problem. I only know of one transparent.


 
 Don't say that on head-fi!


----------



## Bazirker

uchihaitachi said:


> Don't say that on head-fi!


 
  
 Hahahaha spot on!!


----------



## diamondears

castleofargh said:


> o2 is transparent, leckerton is transparent. so different house sound is going to be a problem. I only know of one transparent.


Hehe...you're right...there can't be different transparent "house sounds"...maybe I should have used neutral also like the O2 but with different house sound. 

So the Leckerton is very similar to the O2's sound, eh?


----------



## castleofargh

diamondears said:


> castleofargh said:
> 
> 
> > o2 is transparent, leckerton is transparent. so different house sound is going to be a problem. I only know of one transparent.
> ...


 

 with my limited testing methods(volume matched and a switch but no blind testing), they're pretty darn hard to tell apart. I won't pretend like they would sound the same to everybody on any headphone, but I doubt I could abx them successfully with most "portable" uses. 
 of course when using a very sensitive IEM, I can tell the O2 from the leckerton sometimes thanks to some channel imbalance in my O2 at very low volume setting.
 and for hard to drive headphones, the O2 added power(significantly more) can also become an audible fact. depending on what you plan to use, you may want to check the power output and the gain values. some were bummed out, but the settings are allowing for a better IEM experience and volume setting. no point using a 1W amp and then kill it down to 8mW with a lousy volume control if from the start it was to use with IEMs. different amps for different purpose IMO.
  
 but with average sensitivity portable headphones, both sound neutral, both have reasonably low impedance so they don't mess around too much with IEM's signatures, *both are the most hissless portable devices I had in my hands*. the reason I still have both. but again it really matter mostly on sensitive IEMs. 
  
 can't talk about the DAC section, to me they're all so close that I just don't bother wondering which is best. just that the 6mkII can survive longer with one charge when using the internal DAC I think, so I would have bought it instead if I had planned to mainly use the internal DAC. the amp part is what I use mostly, I only really plug the DAC into a tablet when I'm on a train or on a plane and it's to watch movies anyway, so my feedback on DACs won't help anybody ^_^.


----------



## diamondears

castleofargh said:


> with my limited testing methods(volume matched and a switch but no blind testing), they're pretty darn hard to tell apart. I won't pretend like they would sound the same to everybody on any headphone, but I doubt I could abx them successfully with most "portable" uses.
> of course when using a very sensitive IEM, I can tell the O2 from the leckerton sometimes thanks to some channel imbalance in my O2 at very low volume setting.
> and for hard to drive headphones, the O2 added power(significantly more) can also become an audible fact. depending on what you plan to use, you may want to check the power output and the gain values. some were bummed out, but the settings are allowing for a better IEM experience and volume setting. no point using a 1W amp and then kill it down to 8mW with a lousy volume control if from the start it was to use with IEMs. different amps for different purpose IMO.
> 
> ...



Thanks. Just what I'm looking to hear/read. Cheers.


----------



## Frederick Wang

Itching for one to pair up with my er4s
 but they are out of stock, bummer


----------

