# Icon Audio HP8/MP 3



## Ozer

This is two very uncommon amps... Can't find anything about it on any forums.... I want to know if anyone know anything about it ?
   
  I want to buy a new amp, but the problem is that I don't want to pay import duties, as the import duties is 45% of the price here in Sweden... I have to buy inside EU if I don't want to pay that. It's really hard to find any amps here in EU....
   
  I found out about Icon Audio HP8, and I know where to buy it here in EU, by Audioaffair (http://www.audioaffair.co.uk/index.php?act=viewProd&productId=1402) or from them self...but as I've said I can't find any impressions about it... Then I found on their site that there's a newer headphone amp, Icon Audio MP3, it costs 40£ more, but I don't know if it's much better.... It looks very well made and everything. I've also read that they can upgrade to better tubes and capacitors if you buy from them....
   
  I know that someone will post an identical Ming Da amp.... It's cause Ming Da and Icon Audio uses the same production facility and share technology with each other....
   
  Here's Icon Audio's site: http://www.iconaudio.com/index2.htm
   
  The MP8 uses: 2 x Russian 6H30pi super triodes
                         1 x ECC81 first stage valve
   
   
  If you have some tips on other tube amps I can buy in EU here's my requirements.
  I'm looking for an amp that is leaning to the warmer side rather than the light.
  My budget is a maximum of 700$
  Good with Sennheiser HD650
   
   
  EDIT: NVM about the MP3... Just read on their site that it's suitable for headphones between 4-60 Ohm... I use Senn HD650....


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## Skylab

Well, as I posted elsewhere, that sure looks like this Meixing amp, which has been around forever:
   
  http://cgi.ebay.com/Meixing-MingDa-MMC66-AE-Vacuum-Tube-HEADPHONE-Amplifier-/390186065182
   
  So maybe the take that Chinese amp and mod it?


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## Ozer

Quote: 





skylab said:


> Well, as I posted elsewhere, that sure looks like this Meixing amp, which has been around forever:
> 
> http://cgi.ebay.com/Meixing-MingDa-MMC66-AE-Vacuum-Tube-HEADPHONE-Amplifier-/390186065182
> 
> So maybe the take that Chinese amp and mod it?


 

 Maybe... Is the Ming Da version good?


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## Ozer

Somebody has to know something about this amp.....


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## Skylab

I've never heard it so I cannot say.


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## Ozer

Ok, I know that apparently nobody have heard/heard about this amp (Icon Audio HP8), but I maybe will take a chance and buy one of those, I can send it back if I don't like it...
  
I'm wondering if the tubes on the Icon Audio HP8 is good..... I've mailed Icon Audio for some question, and they responded that they have a MKII version  the amp witch is upgraded... This amp uses 6SN7 tubes... And I think it still uses the ECC81 tube... Are these any good ? If you buy from Icon Audio themselves, you can get an upgrade with "Jensen Cu foil paper in oil caps", but I have no idea what this does 
	

	
	
		
		

		
		
	


	




 I also got two pictures of the amp, 'cause it's a totally new product and they haven't updated their homepage with this product yet.... Here's the pictures...


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## Ozer




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## Leonardo_BVB

Hi Ozer, all I can say is that they are a very good company based in Leicester. I have bought direct from them the Icon BA2 buffer preamplifier (Musical Box) and it is built like a tank. They are also very nice to talk to if you give them a call.
  I am thinking in buying one HP8 MkII myself (I have a collection of 6sn7s so it is very tempting) but I have 3 hedphones amplifiers already so I'm thinking Christmas... so I can get my wife in the right mood!
  They are valve specialist so it can only be very good.


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## alvin sawdust

Contacted Icon about the HP8 mkII and they have it in stock.Price is £449 + shipping.They have a 30 day refund policy with a 10% restocking fee + shipping back to them.
   
  Tempting,especially as my darkvoice 337se has died on one channel.


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## Painterspal

I thought I'd resurrect this thread. Anyone care to share any thoughts on the Icon HP8 mk2? Anyone heard it? I'd be particularly interested in how it might compare to other competing products such as the Little Dot IV se, Woo Audio WA6 or Dark Voice 336 etc.
   
  Thanks All.


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## Xymordos

Mingda's version of the amp...I can say for IEMs it'll suck. There's much too much hiss for them. I've never heard them on a full sized can so I don't know. The sound signature is very tubey, but I found the details to be lacking.


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## Painterspal

Thanks for your reply. It's the more recent MK2 version of the HP8 that interests me - pictured in post 6 above. It looks completely different to the earlier version and the spec seems different. Has anyone actually heard it - especially with full size cans?


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## project86

Quote: 





painterspal said:


> Thanks for your reply. It's the more recent MK2 version of the HP8 that interests me - pictured in post 6 above. It looks completely different to the earlier version and the spec seems different. Has anyone actually heard it - especially with full size cans?


 
   
  I've got one that I've been playing with recently, soon to be reviewed at InnerFidelity. Spoilers - it's very well built, and sounds good too. Easily as good an anything else I've heard for the price. I like it with my D7000, Thunderpants, and especially W1000x. 
   
  I'll add a link to the full review when I have it completed.


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## Painterspal

Thanks project86, much appreciated and I'll certainly look forward to that review. Your V200 review certainly helped tip the balance for me into making that purchase, and I was very happy with the outcome. Now I'm on the tube trail and being in the UK, one of these could really work for me.


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## alvin sawdust

Is the review any closer project86?


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## project86

Quote: 





alvin sawdust said:


> Is the review any closer project86?


 
   
   
  Getting there. Slowly though. I've got 2 things ahead of it, and then assuming I can get all my annoyingly-detailed questions answered in time from Icon Audio, I'll have the review up after that. If I could get more time to write I'd be done by now, but family and "real" work come first.


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## alvin sawdust

Ok thanks. Yeah family and work definitely come first.


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## project86

Having said that, the HP8 mkII is really sounding great with several different headphones I'm using. Currently borrowing the Audio Technica AD2000 from a friend and it is a great pairing, as is the W1000x. Thunderpants TP1 is good but not perfect, but Lawton LA7000 is really nice. I also love the HD650 on this thing - it reminds me that the HD650 was a flagship headphone for many years and is still a really good performer.


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## Painterspal

I've gone ahead and bought the SE version of the HP8 mk2. Still burning in (currently around 70hrs) but I'm quite impressed so far. I'll post some impressions soon, I'm just waiting for a new cable so that I can hook it up to my DAC alongside my v200 and switch easily between the two. So far my ears are telling me that it will give the v200 a run for its money.
   
  The SE version uses Treasure CV181’s in place of the standard Shuguang 6SN7s’ - these are a direct replacement - and a gold pin JJ 12AX7/ECC83 in the front end. I also have a NOS ecc83 tesla on the way which will be interesting too.
   
  Like project86 I think it shines with the HD650s but I've been using it mainly with my LCD-2r2s.


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## alvin sawdust

Quote: 





painterspal said:


> I've gone ahead and bought the SE version of the HP8 mk2. Still burning in (currently around 70hrs) but I'm quite impressed so far. I'll post some impressions soon, I'm just waiting for a new cable so that I can hook it up to my DAC alongside my v200 and switch easily between the two. So far my ears are telling me that it will give the v200 a run for its money.
> 
> The SE version uses Treasure CV181’s in place of the standard Shuguang 6SN7s’ - these are a direct replacement - and a gold pin JJ 12AX7/ECC83 in the front end. I also have a NOS ecc83 tesla on the way which will be interesting too.
> 
> Like project86 I think it shines with the HD650s but I've been using it mainly with my LCD-2r2s.


 
  Ahh it was you who bid for it in the dying seconds?  Strange how he dropped the price then upped it several times.
   
  Please let us know your impressions after some good burn in.


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## Painterspal

Quote: 





alvin sawdust said:


> Ahh it was you who bid for it in the dying seconds?  Strange how he dropped the price then upped it several times.
> 
> Please let us know your impressions after some good burn in.


 

 Not me, I bought mine direct from Icon Audio - best option for me as I'm in the UK. I'll certainly post my impressions though - more people need to get to know what this very nice amp can offer.


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## alvin sawdust

Quote: 





painterspal said:


> Not me, I bought mine direct from Icon Audio - best option for me as I'm in the UK. I'll certainly post my impressions though - more people need to get to know what this very nice amp can offer.


 
  Ok right. One just sold on fleabay for £450 with Shugang Treasure bottles and Jenson paper in oil caps, was very tempted.


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## Painterspal

Quote: 





alvin sawdust said:


> Ok right. One just sold on fleabay for £450 with Shugang Treasure bottles and Jenson paper in oil caps, was very tempted.


 

 It's a steal at that price.


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## alvin sawdust

Any post burn-in impressions on this amp?


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## project86

Yep, but I'm sort of waiting for my full review at InnerFidelity to describe it in depth. The designer is doing some travelling, so I'm waiting for his return to finish our discussion about design choices.
   
  In a nutshell - it's a really good amp. Has an excellent "tube sound" without being overly dark or slow. It's rich and warm and tends to bring out the best in average recordings as well as most headphones.


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## alvin sawdust

Thanks for the quick response.


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## Spakka

Hi, I know you're still writing the review, but those who have this amp I'm considering getting it to use with my ah-w1000x and possible future HD800 or LCD-2r2. Would it be a good match for the latter headphones? 

In terms of value - good/worth it/bad? 

Thanks!


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## Spakka

double post - delete this one please.


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## ScuderiaHeadFi

Interestingly, I'm looking for a dedicated headphone amp for my own W1000X.  This Icon sounds really tempting and I'll be looking forward to the review.  Hoping to learn about the connectivity options, though - seems like a single RCA input with a single TRS headphone jack, right?  Which I could work with, if the sound is truly stellar, but of course the rest of my system might need a little reworking to make everything work for me...
   
  MusicDirect is selling it for $1K...


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## project86

Quote: 





scuderiaheadfi said:


> Interestingly, I'm looking for a dedicated headphone amp for my own W1000X.  This Icon sounds really tempting and I'll be looking forward to the review.  Hoping to learn about the connectivity options, though - seems like a single RCA input with a single TRS headphone jack, right?  Which I could work with, if the sound is truly stellar, but of course the rest of my system might need a little reworking to make everything work for me...
> 
> MusicDirect is selling it for $1K...


 
   
  Yep, it's very simplistic in terms of input and output. I guess "purposeful" would be the correct term. This could be troublesome depending on the rest of your gear, and is therefore one of my few minor gripes about the unit.


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## Painterspal

Quote: 





spakka said:


> Hi, I know you're still writing the review, but those who have this amp I'm considering getting it to use with my ah-w1000x and possible future HD800 or LCD-2r2. Would it be a good match for the latter headphones?
> In terms of value - good/worth it/bad?
> Thanks!


 
   
  I can't comment on the former but I liked mine with the LCD2r2 and absolutely love it with the HD800, which I'm currently using. To put that in context I should add that I prefer the HD800 to the LCD  with other amps too, it wasn't really a reflection on that particular combination. I should add that I'm using the SE version which is upgraded from the standard specification. It's a fine amp and I really like it.


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## Spakka

Quote: 





painterspal said:


> I can't comment on the former but I liked mine with the LCD2r2 and absolutely love it with the HD800, which I'm currently using. To put that in context I should add that I prefer the HD800 to the LCD  with other amps too, it wasn't really a reflection on that particular combination. I should add that I'm using the SE version which is upgraded from the standard specification. It's a fine amp and I really like it.


 
   
   
  I took the plunge a month or so ago, as one came up for £350 2nd hand. Got some nice new tubes etc. 
   
  It's sounding great with my HD800 (arrived this morning so first impressions, pinch of salt, etc. etc.), maybe it's just me but I have no idea why they could be described as bass-light. 
   
  Sounds lovely with my W1000X if sometimes a little bass heavy for my tastes (I don't like heavy bass), and actually made my K702s listenable by allowing them to express some bass rather than none as from my previous amp. 
   
   
  It's also built so well I feel if I dropped it out the window all it'd do is dent the pavement.


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## ScuderiaHeadFi

Quote: 





spakka said:


> I have no idea why they could be described as bass-light.


 
   
  Spakka, where did you see the HP8/MP3 described as bass-light? Since my two cans for home use are some aging Ultrasone PRO-2500 and the Audio-Technica ATH-W1000X (the former being a bass-heavy phone, the latter having a frustrating upper bass hump), I have really wanted an amp that can tame the bass in both sets while leaving alone the beauty of, especially, the W1000X. So I'm going to be very sensitive on the issue of bass control.... I'd just like to see the comments describing the bass of the Icon so I can judge for myself the writer's perspective/matching gear/etc. and determine how much that applies to my case.


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## ScuderiaHeadFi

Quote: 





painterspal said:


> I should add that I'm using the SE version which is upgraded from the standard specification. It's a fine amp and I really like it.


 
   
  I haven't seen any mention of an alternate version of the Icon.  Where did you find it?  How much was it?  What are the differences?


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## Spakka

Quote: 





scuderiaheadfi said:


> Spakka, where did you see the HP8/MP3 described as bass-light? Since my two cans for home use are some aging Ultrasone PRO-2500 and the Audio-Technica ATH-W1000X (the former being a bass-heavy phone, the latter having a frustrating upper bass hump), I have really wanted an amp that can tame the bass in both sets while leaving alone the beauty of, especially, the W1000X. So I'm going to be very sensitive on the issue of bass control.... I'd just like to see the comments describing the bass of the Icon so I can judge for myself the writer's perspective/matching gear/etc. and determine how much that applies to my case.


 
  Sorry I was referring to the HD800. I haven't heard many amps so I don't feel I can comment on the relative bass of the HP8. All I can say is that the bass is well extended and controlled on the HD800 with the HP8 MK2. I am very much not a fan of large amounts of bass; I'm very sensitive to it and get fatigued fast. It can indeed be a bit boomy, but only occasionally, with the W1000X, but hasn't been at all with the HD800.
  My previous headamp had pretty extreme bass rolloff so I got used to that signature, but the HP8 is much, much more satisfying, controlled and natural. 
   
   
  The SE edition is a special thing you can ask for from the factory, it's just upgraded tubes and caps. There isn't an official 'SE' version though.


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## Painterspal

That's right, the SE edition just has upgraded caps and tubes. I've no idea what the stock version sounds like but the SE version sounds terrific and the sound improved significantly over the first 100-200 hours. I've also done a bit of tube rolling, replacing the supplied gold pin JJ ecc83 with various nos options such as Tesla and Mullard. They have improved the sound still further and, with my hd800, I'm frequently astonished how good it now sounds. I agree with the other comments regarding bass from the hd800 with this amp - there's nothing anaemic about the sound. I'm now convinced that the HP8 mk2 is outperforming my Violectic v200 with virtually all the material I throw at it.


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## ScuderiaHeadFi

Ah, I misread the sentence!
 Better than the Violectric?  That's a really exciting proposition, especially the SE version with improvements coming from further tube rolling...


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## project86

My review of the HP8 is finally ready to read: see it HERE.
   
  This is a stunning amp overall - as happy with current-hungry planars as it is with voltage-hungry high impedance dynamics. Very impressive and definitely a contender at its price.


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## alvin sawdust

Excellent review. Helpful that you have such an array of headphones to test the amp with, very informative.
   
  Thanks.


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## project86

Quote: 





alvin sawdust said:


> Excellent review. Helpful that you have such an array of headphones to test the amp with, very informative.
> 
> Thanks.


 
   
   
  Thanks for reading it - glad it was useful.


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## zenpunk

Can the 6SN7 be swapped with 6SL7 tubes? I happened to have a nice collection of those..


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## project86

Quote: 





zenpunk said:


> Can the 6SN7 be swapped with 6SL7 tubes? I happened to have a nice collection of those..


 
   
  I'm guessing yes but I'd check with Icon to be sure. The 6SN7/6SL7 relationship is something like that of the 12AX7/12AU7. Some amp designs won't care at all and some will definitely object. 
   
  If I recall correctly the 6SL7 will have higher gain so it might not be desirable. This amp doesn't need more gain.


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## Paul Meakin

Another thanks for the review. As I'm in the UK this looks like something of a bargain for the price.


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## project86

Yes, UK buyers have it particularly good with this one.

Btw if people enjoy the review feel free to comment on it (on the review itself rather than here). Those are always good as it makes it look like people actually read it and enjoy. Thanks for the support everyone!


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## Spakka

Yes I agree with your review. 
   
  I feel I got an awesome bargain as I got it 2nd hand for about £350, it's built in such a solid feeling way that if I dropped it out my window the pavement would be much worse off than the amp.
   
  I agree with your thoughts on the W1000X pairing, I find the bass a bit too much when using them together, but the HD800 is excellent. 
   
   
  I think the strong sales are because English hifi magazines have recently given it very good reviews - so I suppose more people here have heard of Icon. 
   
   
   
  Hmm, I have realised I never tried anything other than high output impedance with my HD800s, I'll have to compare the L and M soon...
   
   
   
   
  EDIT:
   
  One criticism I have is that there  is quite noticeable tube hum with the Icon - definitely worst on the higher output impedences. It's perhaps something to avoid if you're v.sensitive to this, and use sensitive cans.


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## ScuderiaHeadFi

Thanks Project86!  I'm actually on my way to AXPONA in Chicago right now (as soon as I submit this comment) to see what good preamp/headphone amps I might find.  You make the Icon sound tempting, but I'm still not sure it offers the connectivity I need...


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## project86

scuderiaheadfi said:


> Thanks Project86!  I'm actually on my way to AXPONA in Chicago right now (as soon as I submit this comment) to see what good preamp/headphone amps I might find.  You make the Icon sound tempting, but I'm still not sure it offers the connectivity I need...




Connectivity is the one area where this amp doesn't excell. Not that it is bad - lots of amps have a single input. It's sort of the purist approach. But it does make it a little less useful in complex systems.


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## blasjw

Here's a fresh review of the HP-8 by John Grandberg on InnerFidelity:
   
http://www.innerfidelity.com/content/icon-audio-hp8-mk2-tube-headphone-amplifier


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## project86

Quote: 





blasjw said:


> Here's a fresh review of the HP-8 by John Grandberg on InnerFidelity:
> 
> http://www.innerfidelity.com/content/icon-audio-hp8-mk2-tube-headphone-amplifier


 
   
  That guy's a terrible writer. Can't stand him.


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## blasjw

Quote: 





project86 said:


> That guy's a terrible writer. Can't stand him.


 
   
  Tell me how you really feel.  
	

	
	
		
		

		
			





  On a more serious note, what don't you like about his writing?


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## lithium1085

Quote: 





blasjw said:


> Tell me how you really feel.
> 
> 
> 
> ...


 
  Go ahead Project86.....explain it slowly and in excruciating detail what is it that you don't like? It will be good moment for introspection...


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## blasjw

Quote: 





lithium1085 said:


> Go ahead Project86.....explain it slowly and in excruciating detail what is it that you don't like? It will be good moment for introspection...


 
   
  Wait.  Project86 *is* John Grandberg.


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## lithium1085

Quote: 





blasjw said:


> Wait.  Project86 *is* John Grandberg.


 
  did you shout eureka?


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## blasjw

Quote: 





lithium1085 said:


> did you shout eureka?


 
  lol, no I was just surprised when I actually looked at his sig. showing that the HP8 review was done by him.


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## project86

Yeah, I was just messin with ya.


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## lithium1085

Quote: 





project86 said:


> Yeah, I was just messin with ya.


 
  This has been good fun....


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## donlin

John, thanks for the excellent review.  It's great that this amp is getting some exposure on Head Fi.  I've had one for about two months and continue to be amazed at the sound quality and extremely solid build quality for $1000.00!  This amp drives my LCD-2.2's with more authority than anything else I've tried.  Another aspect I really appreciate, especially for a powerful tube amp, is that at the highest volume setting, there is absolutely no hiss audible on the headphones-just dead silence.  I spoke to David Shaw at Axpona last weekend and he seemed very surprised that I already owned one of their amps.


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## project86

David Shaw is a super nice guy. We went back and forth via email many times during my review prep, and he was always exceedingly helpful. Sometimes people just answer my questions in a matter-of-fact sort of way, which is fine, but other times you get a sense of their passion for audio - which is what I got from David. 
   
  He's funny in that he works differently than a lot of popular audio companies. If you look at Schiit for instance - and this is not a knock on them at all, it's just an example - they seem very well aware of what the market is, and release products very carefully designed to fit in the various spots in said market. In contrast, David Shaw seems like the type who just builds stuff he would want to listen to, without a clue if others will have any interest in buying it. I'm not judging this as a good thing or bad thing, just pointing it out.
   
  It's funny that he was surprised to meet an HP8 owner!
   
  The HP8 is a great amp though. It sort of combines the traits of my Violectric V200 (powerful, direct, smooth) and my Analog Design Labs Svetlana 2 (airy, precise, beautiful) into one amp. Not that it succeeds in replacing them but it does compete on the same level.


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## donlin

Quote: 





project86 said:


> David Shaw is a super nice guy. We went back and forth via email many times during my review prep, and he was always exceedingly helpful. Sometimes people just answer my questions in a matter-of-fact sort of way, which is fine, but other times you get a sense of their passion for audio - which is what I got from David.
> 
> He's funny in that he works differently than a lot of popular audio companies. If you look at Schiit for instance - and this is not a knock on them at all, it's just an example - they seem very well aware of what the market is, and release products very carefully designed to fit in the various spots in said market. In contrast, David Shaw seems like the type who just builds stuff he would want to listen to, without a clue if others will have any interest in buying it. I'm not judging this as a good thing or bad thing, just pointing it out.
> 
> ...


 
  Exactly correct about David Shaw, he was very friendly and enthusiastic and completely unpretentious.  Icon had a great sounding speaker setup at Axpona and I overheard people commenting on the quality of sound.


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## project86

Quote: 





donlin said:


> Exactly correct about David Shaw, he was very friendly and enthusiastic and completely unpretentious.  Icon had a great sounding speaker setup at Axpona and I overheard people commenting on the quality of sound.


 
  It's cool that you got to hear it. Pics? 
	

	
	
		
		

		
		
	


	



   
  It's funny because I've seen plenty of threads about "Why don't any high end amp manufacturers make headphone amps?" Yet here's an example of just that. Granted, Icon might not be priced like Lamm, Atma-sphere, Jadis, etc. But still. 
   
  I was just checking out the Icon MB90 monoblocks. Those look mighty tasty for $4200.


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## blasjw

Quote: 





project86 said:


> It's cool that you got to hear it. Pics?
> 
> 
> 
> ...


 
   
  Or, how about the Jolida Fusion monblocks?  Oh darn... That's $2999 ea.


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## project86

Quote: 





blasjw said:


> Or, how about the Jolida Fusion monblocks?  Oh darn... That's $2999 ea.


 
   
  Those look nice, but I think I'd take the Icon option based on price, looks, and tube compliment.


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## donlin

Quote: 





project86 said:


> It's cool that you got to hear it. Pics?
> 
> 
> 
> ...


 
  Sorry, I didn't take any pictures but there is a grainy photo on the Stereophile website.


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## deniall83

I like what I'm hearing in this thread. So the HP8 pairs well with the HD650?


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## project86

Quote: 





deniall83 said:


> I like what I'm hearing in this thread. So the HP8 pairs well with the HD650?


 
   
  Yes, very much so. I like it set with the "medium" impedance setting which makes the HD650 seem to dig deeper in the bass region. Very, very nice indeed.


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## Painterspal

Great to see your review project86. I've been putting some thoughts together on the Icon too, but it'll be very boring because I agree with you completely. Oh well!
   
  I'm still loving my Icon and have settled on what I think is an outstanding tube combination: Shuguang Treasure CV181Z and Mullard MC1. It's a perfect balance between insight and euphony. Combined with my HD800 it's pure bliss.
   
  Loved the accidental humour in this thread too - simply joyous and totally brightened up my day.
   
  Amazed this little amp isn't more appreciated.


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## project86

Quote: 





painterspal said:


> Great to see your review project86. I've been putting some thoughts together on the Icon too, but it'll be very boring because I agree with you completely. Oh well!
> 
> I'm still loving my Icon and have settled on what I think is an outstanding tube combination: Shuguang Treasure CV181Z and Mullard MC1. It's a perfect balance between insight and euphony. Combined with my HD800 it's pure bliss.
> 
> ...


 
   
   
  Thanks! I'd still be interested in seeing your write-up, regardless of what's already been covered. Just because I say something, doesn't make it so, and all other viewpoints are always welcome - even if it's mostly in agreement.
   
  I'm also surprised this amp isn't more well regarded. It's a great amp. But like my Analog Design Labs tube amp, not many people seem to have even heard of it much less are interested in spending 4 figures on it. Oh well, their loss.


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## Painterspal

I'll certainly post my review - it's 3/4 done now anyway - and, as you would expect, my approach is somewhat different. However, where we overlap our impressions are similar, strikingly so where the HD800 is concerned, which is the 'phone I've mainly focused on.
   
  I'd certainly like to hear the Beyer T1 with the Icon - sounds like a great combination.
   
  With the exchange rate for UK exports now more favourable, I hope others will take the chance to sample the delights of this amp, which competes strongly at around the $1K price point IMO.


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## project86

Quote: 





painterspal said:


> I'll certainly post my review - it's 3/4 done now anyway - and, as you would expect, my approach is somewhat different. However, where we overlap our impressions are similar, strikingly so where the HD800 is concerned, which is the 'phone I've mainly focused on.
> 
> I'd certainly like to hear the Beyer T1 with the Icon - sounds like a great combination.
> 
> With the exchange rate for UK exports now more favourable, I hope others will take the chance to sample the delights of this amp, which competes strongly at around the $1K price point IMO.


 
   
  Yes, T1 is excellent with the Icon. Perhaps the best I've ever heard it sound. 
   
  I especially look forward to reading your thoughts about various tube options (if that's included in your write-up, if not that's OK).


----------



## Painterspal

Yup, will cover the tubes I've used and their effect on the sound.


----------



## donlin

Without getting into expensive or NOS tubes, I think the current production Tung-Sols in all positions is a nice improvement over the stock Chinese tubes.  The 12AX7 switch is the most noticeable, better resolution and less sibilant treble.


----------



## Spakka

I've replaced mine with 2X Full music 6SN7 and a Genelex Gold Lion 12AX7. I felt they were all a big upgrade from stock (but mine were 2nd hand, no idea how many hours on stock), better resolution etc, with reduced background noise. 
   
  I didn't like the PSVane 12AX7 though, didn't feel right.


----------



## lithium1085

Quote: 





painterspal said:


> I'll certainly post my review - it's 3/4 done now anyway - and, as you would expect, my approach is somewhat different. However, where we overlap our impressions are similar, strikingly so where the HD800 is concerned, which is the 'phone I've mainly focused on.
> 
> I'd certainly like to hear the Beyer T1 with the Icon - sounds like a great combination.
> 
> With the exchange rate for UK exports now more favourable, I hope others will take the chance to sample the delights of this amp, which competes strongly at around the $1K price point IMO.


 
  It would be great to read your review. Also has anyone heard the Icon audio mp3? It seems a weird amp that is rated for 4-60 ohm headphones


----------



## project86

Thanks for the info about tubes. I tried some that I liked but nothing really made me fall in love with it - maybe I just need to spend more time to get to know each set. 
   
  Quote: 





lithium1085 said:


> It would be great to read your review. Also has anyone heard the Icon audio mp3? It seems a weird amp that is rated for 4-60 ohm headphones


 
   
  It sure does. Not attractive imo, from an external standpoint. And reminds me of some Chinese amps I have seen (which I can't recall the brand at the moment.... maybe Ming Da?)


----------



## lithium1085

Quote: 





project86 said:


> Thanks for the info about tubes. I tried some that I liked but nothing really made me fall in love with it - maybe I just need to spend more time to get to know each set.
> 
> 
> It sure does. Not attractive imo, from an external standpoint. And reminds me of some Chinese amps I have seen (which I can't recall the brand at the moment.... maybe Ming Da?)


 
  yup Ming Da has an amp which looks like this........Is it just me or does anyone else feel that the price difference of the HP8 in the UK/EU and through music direct is a little too high?


----------



## lithium1085

The official price on the icon audio site is 600 pounds. Subtracting 20% EU VAT the price is 480 pounds,i.e, 729 USD. The music direct price being 999 USD, I feel that this is a little unjustifiable to hike the price by almost 271$. Since I am calculating it is an increase of 37.2% over the european price.


----------



## Spakka

Remember shipping of such a heavy amp will be high + additional cost of any warranty issues etc.
   
  In the UK we pay about 50-100% more for identical items when they originate from the US. Works both ways


----------



## lithium1085

Quote: 





spakka said:


> Remember shipping of such a heavy amp will be high + additional cost of any warranty issues etc.
> 
> In the UK we pay about 50-100% more for identical items when they originate from the US. Works both ways


 
  100% !! I find it astonishing that people are ready to pay 100% more ......well I guess I need more money thats all....I just feel that shipping plus some warranty issues don't justify this hike as music direct probably pays less per amp than the average customer. This probably means that the markup is even higher than the general maximum retail prices that I have used for the calculation.


----------



## lithium1085

also they definitely don't ship it one amp at a time, which means shipping costs per amp will be much lower.


----------



## donlin

Quote: 





lithium1085 said:


> also they definitely don't ship it one amp at a time, which means shipping costs per amp will be much lower.


 
  I'm not so sure about that.  Music Direct listed it as "ships today"  the day I bought it and since then it shows availability in "4 to 6 weeks".


----------



## lithium1085

Quote: 





donlin said:


> I'm not so sure about that.  Music Direct listed it as "ships today"  the day I bought it and since then it shows availability in "4 to 6 weeks".


 
  I feel if they shipped one amp at a time they would have ship it from UK to you. If you received your amp from UK then I guess they are shipping them one at a time. Otherwise, they probably order them in consignments. Anyway perhaps I have made this too much of an issue.


----------



## Spakka

The thing is as parts are handmade they are made to order (at least if you order one from the UK), and very few places keep one in stock for auditions etc. 
   
  But yeah it sucks paying more for things because they aren't 'local-ish'. 
   
  Imo it's a very nice amp and worth considering at least.


----------



## lithium1085

What other output transformer coupled amps should I consider in the under 1000$ region?


----------



## lithium1085

Quote: 





spakka said:


> The thing is as parts are handmade they are made to order (at least if you order one from the UK), and very few places keep one in stock for auditions etc.
> 
> But yeah it sucks paying more for things because they aren't 'local-ish'.
> 
> Imo it's a very nice amp and worth considering at least.


 
   
  I am sure considering all the reviews that it must be a really good amp. It's just difficult to keep things in perspective as I (and probably most people) cannot audition a amp before buying it...


----------



## Spakka

Oh I agree being unable to audition most things sucks. 
   
  I was lucky in that I got mine 2nd hand on the back of not seeing many reviews, and happened to be very pleased with my luck!


----------



## lithium1085

Does anyone have any experience with the ten year old consonance cyber-20?


----------



## Tony1110

I'm very close to pulling the trigger on the Icon Audio HP8 to drive my T1's. I'm in the UK and it seems like a viable alternative to the Woo amps without having to go through the hassle of customs/expensive delivery charges etc. I'm yet to read anything negative about the amp and everything points to it being a superb match with the T1.


----------



## lithium1085

Quote: 





tony1110 said:


> I'm very close to pulling the trigger on the Icon Audio HP8 to drive my T1's. I'm in the UK and it seems like a viable alternative to the Woo amps without having to go through the hassle of customs/expensive delivery charges etc. I'm yet to read anything negative about the amp and everything points to it being a superb match with the T1.


 
  according to project86's comparisons it is better than the WA-6 SE and significantly cheaper since you are in the UK


----------



## Tony1110

Yeah, it certainly seems to have the power and the characteristics to be a good match with the T1. The only thing that's keeping me back is that it's a bit of an unknown quantity and nobody seems to have heard it.


----------



## Painterspal

I wouldn't say no one has heard it, there are a few impressions out there.
   
  Whereabouts are you in the UK?


----------



## Paul Meakin

Quote: 





tony1110 said:


> Yeah, it certainly seems to have the power and the characteristics to be a good match with the T1. The only thing that's keeping me back is that it's a bit of an unknown quantity and nobody seems to have heard it.


 
   
  I wouldn't be _too _discouraged by that. Icon have been around for a while and their full sized amps seem to be well regarded (although admittedly this guarantees nothing, anyone can produce a dud).
   
  I suspect they may just be one of those brands that gets somewhat overlooked here on Head-fi (e.g. Naim, Densen, EAR-Yoshino, etc.), which is not that unusual for UK/EU manufactured kit... maybe due to a big price hike for transport and import duty? This holds for North American kit being imported into the UK, it's pretty typical to just change the $ symbol to a £ and leave the numbers unchanged.
   
If you are in the UK and anywhere near Sussex, I think I remember reading that Hi-Fi headphones might have one on demonstration. Or try Icon directly if you are in the Midlands.


----------



## lithium1085

Quote: 





tony1110 said:


> Yeah, it certainly seems to have the power and the characteristics to be a good match with the T1. The only thing that's keeping me back is that it's a bit of an unknown quantity and nobody seems to have heard it.


 
  have you seen project 86's review in this thread?


----------



## project86

Quote: 





tony1110 said:


> Yeah, it certainly seems to have the power and the characteristics to be a good match with the T1. The only thing that's keeping me back is that it's a bit of an unknown quantity and nobody seems to have heard it.


 
   
  Yep, that's a downside of sorts. Some people do care about prestige and such - even if you don't, that sort of thing plays a role in determining resale value on the used market. Not that you necessarily intend to sell your new amp anytime soon but things happen. The trade-off for that is superior sound (imo). 
   
  The Woo stuff is certainly nice though. It's not like you have a good option and a terrible one - more like good and better.


----------



## smial1966

Just to let potential UK purchasers know that if they buy direct from Icon Audio, they make each HP8 to order and lead time from ordering to delivery is two weeks.
   
  Adrian Feary (Icon Audio) phoned today to confirm that there'll be someone at my delivery address this Thursday to accept delivery of the HP8. 
   
  Great customer service and I'm proud to buy British.
   
  Cheers,
   
  Andy.
   
  P.S. HP8 impressions to follow in a week or so.


----------



## project86

Nice!


----------



## Painterspal

Quote: 





smial1966 said:


> Just to let potential UK purchasers know that if they buy direct from Icon Audio, they make each HP8 to order and lead time from ordering to delivery is two weeks.
> 
> Adrian Feary (Icon Audio) phoned today to confirm that there'll be someone at my delivery address this Thursday to accept delivery of the HP8.
> 
> ...


 

 Nice to hear that you're joining the Icon club Andy - I think you're going to be pleased with your purchase. Mine continues to amaze me with its performance.


----------



## Tony1110

Oh no, I'm not at all interested in prestige brands and like Andy I'll also be proud to buy British, should I opt for the Icon. What I value is superior sound and good value. I was a little deterred as the only decent review I could find was John's and you know how reviewers' opinions often differ. I'm in the North East so getting a demo wouldn't be easy for me. 

I'd be very interested in hearing your views, Andy. I placed a bid on the Cary amp you were selling on eBay and I know you were also selling a WA6 not so long ago. Be sure to let us know how the Icon stacks up against them.


----------



## zenpunk

While those amps are said to be designed in England I am pretty sure they are made in China .
  Please correct me if I am wrong.


----------



## lithium1085

Quote: 





zenpunk said:


> While those amps are said to be designed in England I am pretty sure they are made in China .
> Please correct me if I am wrong.


 
  I actually checked up on this and though there is a ming da amp which resembles the mp3 amp, I could not find one that resembles the HP8. So I still believe the designed in UK tag


----------



## project86

Quote: 





zenpunk said:


> While those amps are said to be designed in England I am pretty sure they are made in China .
> Please correct me if I am wrong.


 
   
   
  I think that's correct. Or at least some of the work is done in China. When I spoke with designer David Shaw he was in China for a long period of time.


----------



## Spakka

Quote: 





lithium1085 said:


> I actually checked up on this and though there is a ming da amp which resembles the mp3 amp, I could not find one that resembles the HP8. So I still believe the designed in UK tag


 
   
  The original HP8 (Mk I) looked like the ming das, and I think was wholly made over there. The Mk II however is a new design and I think is made partially there, partially in the UK.


----------



## smial1966

Ah yes, I divested myself of two fine headphone amps (Cary HH-1 and WA6) in my haste to adopt computer audio, regret my impulsiveness at selling both and have purchased the HP-8 to appease my regretful musical soul!  
	

	
	
		
		

		
		
	


	



   
  Cheers,
   
  Andy. 
   
  Quote: 





tony1110 said:


> Oh no, I'm not at all interested in prestige brands and like Andy I'll also be proud to buy British, should I opt for the Icon. What I value is superior sound and good value. I was a little deterred as the only decent review I could find was John's and you know how reviewers' opinions often differ. I'm in the North East so getting a demo wouldn't be easy for me.
> 
> I'd be very interested in hearing your views, Andy. I placed a bid on the Cary amp you were selling on eBay and I know you were also selling a WA6 not so long ago. Be sure to let us know how the Icon stacks up against them.


----------



## Spakka

Quote: 





smial1966 said:


> Ah yes, I divested myself of two fine headphone amps (Cary HH-1 and WA6) in my haste to adopt computer audio, regret my impulsiveness at selling both and have purchased the HP-8 to appease my regretful musical soul!
> 
> 
> 
> ...


 
   
   
  Well you'll be very pleased with your purchase then! The HP8 is a really nice amp, and very versatile with the output impedance switch.
   
  What will you be pairing it with?


----------



## Tony1110

Andy sells some really nice gear at great prices. I'd have snapped up that CD player a few months ago but I'm also transitioning into computer audio and am in the process of flogging all my CDs as well as my Graham Slee Solo, Music Streamer ii and Grado PS500's. I'll be using the proceeds to fund a Benchmark DAC and a nice tube amp for my T1's - probably the HP8. As far as tube amps go, there's only the Earmax and Icon readily available in the UK. For some reason, the Earmax doesn't appeal.


----------



## smial1966

I'm planning to use my HD650 with a Piccolino cable that young Frank (Mr. Toxic) has constructed for them, plus an LCD2 with another of Franks superb cables. Plus possibly an Edition 8 if my friend is amenable to an extended loan.
   
  Cheers,
   
  Andy.
   
  Quote: 





spakka said:


> Well you'll be very pleased with your purchase then! The HP8 is a really nice amp, and very versatile with the output impedance switch.
> 
> What will you be pairing it with?


----------



## smial1966

Sounds good to me, as I definitely think that a separate DAC, amplifier and server and/or streaming device is the way to go. I borrowed a Weiss Man301 and couldn't fault it's functionality and convenience, but it sounded kind of 'sterile' and not especially 'musical' to my ears. I'll try the Lessloss Laminar Streamer when it's released but fear that it's cost will be prohibitively expensive. 
   
  Cheers,
   
  Andy.
   
  Quote: 





tony1110 said:


> Andy sells some really nice gear at great prices. I'd have snapped up that CD player a few months ago but I'm also transitioning into computer audio and am in the process of flogging all my CDs as well as my Graham Slee Solo, Music Streamer ii and Grado PS500's. I'll be using the proceeds to fund a Benchmark DAC and a nice tube amp for my T1's - probably the HP8. As far as tube amps go, there's only the Earmax and Icon readily available in the UK. For some reason, the Earmax doesn't appeal.


----------



## Painterspal

Look forward to hearing your impressions once you've had some time with your new amp Andy. I may get a review (of sorts) complete this weekend - particularly if the weather continues to be foul!


----------



## Spakka

smial1966 said:


> Sounds good to me, as I definitely think that a separate DAC, amplifier and server and/or streaming device is the way to go. I borrowed a Weiss Man301 and couldn't fault it's functionality and convenience, but it sounded kind of 'sterile' and not especially 'musical' to my ears. I'll try the Lessloss Laminar Streamer when it's released but fear that it's cost will be prohibitively expensive.
> 
> Cheers,
> 
> Andy.




How about using the Tera player as the source?


----------



## ab_ba

Project86, based on your innerfidelity review, I'm considering my first tube amp purchase, and seriously considering the Icon. Thank you for peaking my interest! I've also read wonderful things about the Woo WA6 here, so Andy, I'd love to hear your thoughts on that comparison. I listen with JH-13 IEMs, HE-500's, and 650's, so the prospect of a silent background and a lot of power sounds ideal.


----------



## Spakka

ab_ba said:


> prospect of a silent background and a lot of power sounds ideal.





For my HP8 at least the background is not silent. I wouldn't really recommend it with IEMs! It was just about tolerable with W1000X (which are quite sensitive to hiss).


----------



## project86

As Spakka mentioned, the HP8 isn't really idea for ultra-sensitive IEMs. For one, the output impedance is too high - even on the "low" setting. Also, there's potential noise issues with IEMs which tends to be the case on nearly all tube amps.
   
  I noticed my HP8 was very sensitive to ground loop issues. I have one spot in the house with a little system set up, and the HP8 would be super noisy there. The noise came when I plugged in RCA cables, even if those weren't attached to anything yet. Adding the Yulong P18 power conditioner fixed the problem in that spot. But in a different room, nothing I tried was able to get rid of the noise. In other rooms it is totally fine. Some amps are more picky than others when it comes to this type of thing. Also some tubes are more sensitive.


----------



## donlin

Quote: 





spakka said:


> For my HP8 at least the background is not silent. I wouldn't really recommend it with IEMs! It was just about tolerable with W1000X (which are quite sensitive to hiss).


 
  I guess I'm lucky.  With my LCD-2's (obviously way less sensitive than IEM's)  the background is dead silent with all settings on maximum.


----------



## project86

Quote: 





donlin said:


> I guess I'm lucky.  With my LCD-2's (obviously way less sensitive than IEM's)  the background is dead silent with all settings on maximum.


 
   
  LCD-2 is not a good test for sensitivity though - it's good even on noisy amps. W1000X is pretty sensitive but I got it nice and quiet with the HP8 once I fixed the ground loop issues.


----------



## Spakka

Oh I should probably mention I have a ground loop problem - I get crackles when plugging in my laptop via another socket etc. My noise issue isn't just the amp itself. 

I can even get crackles when I touch my laptop with the USB cable from my external HDD.... Nothing I try has solved the problem though, maybe I do need a power conditioner...


----------



## zigy626

I am looking for an amplifier to drive my HD800. Currently I am using the Audiolab M-Dac and Meier Corda Jazz and find the sound to be harsh. Since I am in the UK Icon looks like a really good option but at £600 it is a bit over my budget. I have heard many good things about the Voilectric V100. Wondering which one to go for?


----------



## project86

Quote: 





spakka said:


> Oh I should probably mention I have a ground loop problem - I get crackles when plugging in my laptop via another socket etc. My noise issue isn't just the amp itself.
> 
> I can even get crackles when I touch my laptop with the USB cable from my external HDD.... Nothing I try has solved the problem though, maybe I do need a power conditioner...


 
   
  Even then, a power conditioner doesn't always solve the problem. I have one corner of a room with a little setup where nothing fixes it. I can have just the amp alone, nothing else plugged in, and it's still noisy. Weird. 
   
  Quote: 





zigy626 said:


> I am looking for an amplifier to drive my HD800. Currently I am using the Audiolab M-Dac and Meier Corda Jazz and find the sound to be harsh. Since I am in the UK Icon looks like a really good option but at £600 it is a bit over my budget. I have heard many good things about the Voilectric V100. Wondering which one to go for?


 
   
  I loved the V181 and continue to love the V200, but I haven't yet heard the V100. I did try the Lake People G109 which is very similar to the V100. It's an excellent amp for the price. Sounds more neutral than the HP8. The Icon has a bit of tube warmth, sweetness, whatever you want to call it.


----------



## Tony1110

The Violectric is also an option as it's supposed to pair well with the T1 - although most T1 owners swear by tube amps. Just wish I had the opportunity to audition them both.


----------



## smial1966

Tony1110,
   
  I have the Violectric V200 and now the Icon Audio HP8. You're welcome to audition both if you can get to Norfolk sometime for a demo. 
   
  Cheers,
   
  Andy. 
   
  Quote: 





tony1110 said:


> The Violectric is also an option as it's supposed to pair well with the T1 - although most T1 owners swear by tube amps. Just wish I had the opportunity to audition them both.


----------



## zigy626

Quote: 





smial1966 said:


> Tony1110,
> 
> I have the Violectric V200 and now the Icon Audio HP8. You're welcome to audition both if you can get to Norfolk sometime for a demo.
> 
> ...


 
  Which one out of the two do you like more with your LCD's?


----------



## smial1966

Too early to tell as the HP8 was only delivered yesterday and isn't burnt in yet.
   
  Cheers,
   
  Andy. 
   
  Quote: 





zigy626 said:


> Which one out of the two do you like more with your LCD's?


----------



## Painterspal

Quote: 





project86 said:


> I noticed my HP8 was very sensitive to ground loop issues. I have one spot in the house with a little system set up, and the HP8 would be super noisy there. The noise came when I plugged in RCA cables, even if those weren't attached to anything yet. Adding the Yulong P18 power conditioner fixed the problem in that spot. But in a different room, nothing I tried was able to get rid of the noise. In other rooms it is totally fine. Some amps are more picky than others when it comes to this type of thing. Also some tubes are more sensitive.


 
   
  Interesting you should say that. I had ground loop problems with mine too and found it to be very sensitive to mains noise issues generally. I assumed it was a tube amp thing, rather than a HP8 specific issue. I'd also assumed it was partly that I live in an house with old wiring and noisy appliances in the centre of town.
   
  When I had the HP8 running side by side with my v200 both would exhibit the ground loop problem, but the Violectric was far less badly affected. With that amp I could only hear the hum when the volume was turned up well beyond normal listening levels, and then not very loudly. With the HP8 it was clearly noticeable even at normal listening levels. Eventually I reduced the problem by switching from a mains powered DAC to a USB powered alternative (Meridian Dragonfly), then cured it completely by buying the iFi USB power conditioner. This not only cured the noise but dramatically improved the overall sound too - £ for £ the best upgrade I've ever made. I'm regularly astounded by how revealing and musical it is now. I also found cable placement made a surprising difference too.
   
   Quote: 





			
				smial1966 said:
			
		

> Tony1110,
> 
> I have the Violectric V200 and now the Icon Audio HP8. You're welcome to audition both if you can get to Norfolk sometime for a demo.
> 
> ...


 
  Quote: 





			
				zigy626 said:
			
		

> Which one out of the two do you like more with your LCD's?


 

   
  When I had both I don't remember having a clear preference for either with my LCD2r2 that I owned at the time. However, I eventually decided that I didn't like the LCD full stop, which may have been why neither combination really impressed me. With the HD800 it's a different story.


----------



## zigy626

Quote: 





painterspal said:


> Interesting you should say that. I had ground loop problems with mine too and found it to be very sensitive to mains noise issues generally. I assumed it was a tube amp thing, rather than a HP8 specific issue. I'd also assumed it was partly that I live in an house with old wiring and noisy appliances in the centre of town.
> 
> When I had the HP8 running side by side with my v200 both would exhibit the ground loop problem, but the Violectric was far less badly affected. With that amp I could only hear the hum when the volume was turned up well beyond normal listening levels, and then not very loudly. With the HP8 it was clearly noticeable even at normal listening levels. Eventually I reduced the problem by switching from a mains powered DAC to a USB powered alternative (Meridian Dragonfly), then cured it completely by buying the iFi USB power conditioner. This not only cured the noise but dramatically improved the overall sound too - £ for £ the best upgrade I've ever made. I'm regularly astounded by how revealing and musical it is now. I also found cable placement made a surprising difference too.
> 
> ...


 
  Please expand a bit on the HD800 story. As I own HD800 myself it would be great to get your opinion on the difference between the HP8 and V200.


----------



## Painterspal

Quote: 





zigy626 said:


> Please expand a bit on the HD800 story. As I own HD800 myself it would be great to get your opinion on the difference between the HP8 and V200.


 

 I'll go into it in more detail in my review which I'll try and finish in the next few days.
   
  I ended up preferring the Icon to the Violectric with the HD800. The difference isn't night and day; I like the v200 a lot and consider it a very fine amp. It's more an accumulation of small differences that ultimately meant I found that HP8 a more involving listen. One particular difference, which I found crucial to really enjoying the HD800 fully, is that the Icon manages to provide a little more bass/lower mid weight. It does that without noticeably loosing any tightness/grip and without any sense of exaggeration either. But the additional weight makes the Senns seem fuller, and balances with its already wonderful mids and extended treble. A great pairing IMO.


----------



## zigy626

Quote: 





painterspal said:


> I'll go into it in more detail in my review which I'll try and finish in the next few days.
> 
> I ended up preferring the Icon to the Violectric with the HD800. The difference isn't night and day; I like the v200 a lot and consider it a very fine amp. It's more an accumulation of small differences that ultimately meant I found that HP8 a more involving listen. One particular difference, which I found crucial to really enjoying the HD800 fully, is that the Icon manages to provide a little more bass/lower mid weight. It does that without noticeably loosing any tightness/grip and without any sense of exaggeration either. But the additional weight makes the Senns seem fuller, and balances with its already wonderful mids and extended treble. A great pairing IMO.


 
  Will wait for your review. I think I am going to go for the Icon HP8 when funds permit. I like that the fact that its made in Leicester,UK and has received so many positive reviews from the international press. Plus its a tube amp and since I have mostly used SS amps till now would like to go for something different.


----------



## project86

Quote: 





painterspal said:


> Interesting you should say that. I had ground loop problems with mine too and found it to be very sensitive to mains noise issues generally. I assumed it was a tube amp thing, rather than a HP8 specific issue. I'd also assumed it was partly that I live in an house with old wiring and noisy appliances in the centre of town.


 
   
   
  To some degree it is a tube amp thing. Not all, but most, tend to be more concerned with AC as compared to the average SS counterpart.


----------



## ianmedium

smial1966 said:


> Too early to tell as the HP8 was only delivered yesterday and isn't burnt in yet.
> 
> Cheers,
> 
> Andy.




I will be interested to hear what you think of it in comparison to the TU-05 Andy. Have your Siemens arrived yet?


----------



## Painterspal

Project86: how did you find the Sylvania metal base 6SN7W in the Icon? I've been trying out a pair of the black plastic based large bottle version and am liking the sound quite a bit.


----------



## project86

Quote: 





painterspal said:


> Project86: how did you find the Sylvania metal base 6SN7W in the Icon? I've been trying out a pair of the black plastic based large bottle version and am liking the sound quite a bit.


 
   
  It was probably my favorite, though unfortunately among the most expensive. Very nice liquid midrage though - almost addicting. I didn't try those plastic base large bottle ones though.
   
  Most surprising to me was the Northern Electric 6SN7 - normally I say go NOS before going expensive Chinese reissue, but man are these good! Not as liquid in the midrange but the highs and the details are something special.


----------



## Kevin Brown

I am looking at this amp now vs Woo's new WA7.  This one seems more powerful into low impedance loads.  I'd primarily be using it with Grados, in addition to the Q701, DT880/250, AT AD900x, etc.
   
  Dang.  My WA7 will be here in a few days, and already I'm feeling this might be the better match.  Might have to compare both side by side.


----------



## project86

Quote: 





kevin brown said:


> I am looking at this amp now vs Woo's new WA7.  This one seems more powerful into low impedance loads.  I'd primarily be using it with Grados, in addition to the Q701, DT880/250, AT AD900x, etc.
> 
> Dang.  My WA7 will be here in a few days, and already I'm feeling this might be the better match.  Might have to compare both side by side.


 
   
  Could be better, or maybe not... I'd say listen to your WA7, get to know it, and if you love it.... then enjoy what you have and don't second guess yourself. That sort of thing causes us a lot of unnecessary grief. Now, if you DON'T love the WA7 and feel it's completely worth the money, that's when you might look elsewhere. And the Icon is a good place to look.


----------



## Kevin Brown

^^^
   
  You're exactly right.  This what peaked my interest in the Icon:
   
  Icon:  http://www.innerfidelity.com/content/icon-audio-hp8-mk2-tube-headphone-amplifier  =>
   
  Low setting - 451mW at 32 ohm, 720mW at 50 ohm, 667mW at 150 ohm
   
  WA7:  http://kenrockwell.com/audio/woo/wa7.htm#meas  =>
   
*Output Levels: At the ¼" jack , LO-Z setting; **37.5 Ω*

 *At 0.1% THD *
  115 mV RMS @ 9:30 = 352 µW
 *At 1% THD *
  1.05 V RMS @ 1:00 = 37 mW
 *At Max. Gain *
  5% THD @ 5 V @ max. = 667 mW

   
   
  Substantially more power output by the Icon.  But we don't know what the measurement conditions are for the Icon though, although I'd guess 1%.


----------



## project86

Quote: 





kevin brown said:


> Substantially more power output by the Icon.  But we don't know what the measurement conditions are for the Icon though, although I'd guess 1%.


 
   
  True, I didn't clarify that. I just appreciate the fact that a person actually measured and got these results, rather than quoting a spec from an opamp datasheet or something, as is usually the case.


----------



## zigy626

Ok guys I finally went with the Lehmann Black Cube for my HD800's. Mainly because I read somewhere that Icon Audio HP8/MP3 is only designed in UK but is manufactured in China. Nothing against made in China, my Macbook air is made in China. But to be very frank how much of that £600 asking price for this amplifier is attributed to the fact that it has a designed in UK badge on it.


----------



## hodgjy

Just to play total devil's advocate, how much of your Macbook Air's price stems from a little Apple with a bite out of it that glows when turned on?  How much did you pay for the "Designed by Apple in California" tagline on the bottom?
   
  Quote: 





zigy626 said:


> Ok guys I finally went with the Lehmann Black Cube for my HD800's. Mainly because I read somewhere that Icon Audio HP8/MP3 is only designed in UK but is manufactured in China. Nothing against made in China, my Macbook air is made in China. But to be very frank how much of that £600 asking price for this amplifier is attributed to the fact that it has a designed in UK badge on it.


----------



## zigy626

Quote: 





hodgjy said:


> Just to play total devil's advocate, how much of your Macbook Air's price stems from a little Apple with a bite out of it that glows when turned on?  How much did you pay for the "Designed by Apple in California" tagline on the bottom?


 
  But its the design, how the hardware works with the software, and look at those nicely designed Icons sitting in the Dock. And its made out of Aluminium. Ohhhhhhhhh


----------



## project86

Quote: 





zigy626 said:


> Ok guys I finally went with the Lehmann Black Cube for my HD800's. Mainly because I read somewhere that Icon Audio HP8/MP3 is only designed in UK but is manufactured in China. Nothing against made in China, my Macbook air is made in China. But to be very frank how much of that £600 asking price for this amplifier is attributed to the fact that it has a designed in UK badge on it.


 
   
  It's not so much the location where it was designed, but rather the people who designed it. Icon is a legit company who has been around for a while. They have a solid history behind them making tube related audiophile gear. So that quality shows in the HP8. Yes, you can find a Darkvoice or Little Dot or other quality amp designed in China, and those may be good options.... or you can go with a device made in Germany. Nothing wrong with that.
   
  While we are at it though - you actually pay a lot more for the device being made in Germany as compared to China. I don't know about Lehmann at all, but Violectric is a German company who does everything local. They pay a lot more for their labor, their facilities, their taxes, etc. And that all gets passed down in the final price. Is it worth it? Depends. I love their gear, and I love the Icon HP8. The Violectric gear could be cheaper if it was outsourced to China for production. The Icon would be significantly more expensive if it was built in house at Icon HQ in the UK.


----------



## zigy626

Yeah I guess you are right but I wish they would be a bit more forthright with the information on their website. I wonder if someone would pay £600 for a hp8/mp3 if it had Made in China also printed on it. You can buy a Darkvoice tha337Se dual monaural for £730 because its made in China. And it's internals look like a piece of art (end to end wiring and no printed circuits). It's literally double the Amp when compared to HP8.


----------



## project86

Quote: 





zigy626 said:


> Yeah I guess you are right but I wish they would be a bit more forthright with the information on their website. I wonder if someone would pay £600 for a hp8/mp3 if it had Made in China also printed on it. You can buy a Darkvoice tha337Se dual monaural for £730 because its made in China. And it's internals look like a piece of art (end to end wiring and no printed circuits). It's literally double the Amp when compared to HP8.


 
   
  I tend to assume everything is made in China unless I hear otherwise. That's just the state of things right now. I don't necessarily love it, but then again I'm not sure I want to see the 30-60 percent price increase (or more) that would apply if things changed. It's a tough subject.
   
  Regarding Darkvoice - I owned the 337SE for several years, and it was my reference amp. I like Darkvoice and respect their product, but I'd call the Icon HP8 mkII a superior amp in every way. The 337SE sure _looks _like a more intimidating piece of gear and as I said, it sounds great. But the HP8 is just a whole different league. 
   
  HP8 is also hand wired point to point, and has really well designed output transformers which I assume is the secret to the excellent sound:


----------



## khaine1711

Just dropping in to say curiosity gets the best of me and I received my Icon Hp8 today, not sure why did I get another amp though 
	

	
	
		
		

		
			




   
  Quite surprising to me, but the Hp8 mkii now received the "facelift" treatment like some of their recent statement gear (The La5 pre + 845 mono) - a copper plate on top. Also the paint is matte black instead of glossy black.


----------



## project86

Nice! I actually do like the facelift - the original looks nice enough, but perhaps a little "plain", and sort of blends in compared to the many other fine tube amps out there. This new look is more distinctive.


----------



## alvin sawdust

Quote: 





khaine1711 said:


> Just dropping in to say curiosity gets the best of me and I received my Icon Hp8 today, not sure why did I get another amp though
> 
> 
> 
> ...


 
  Congrats, looks really good. Let us know what you think after it has settled in.
  Slightly OT, seen your Copland for sale on the Wam. What do you think of it powering the HE6?


----------



## khaine1711

Quote: 





alvin sawdust said:


> Congrats, looks really good. Let us know what you think after it has settled in.
> Slightly OT, seen your Copland for sale on the Wam. What do you think of it powering the HE6?


 
  Pretty much the best sound I heard with the he6. It makes me stop bugging dealers for demo speaker amp 
	

	
	
		
		

		
		
	


	




. It does soundstage and piano "right", which are the most important requirements for me. Would have worked as my sole He6 rig if it's missus-approved though.
   
  About the Icon, I think it sounds pretty nice, and the impedance switch has some interesting effect on the He6. The stock tube (the 12AX7 in particular) is crap though, and matched pair of 6sn7 is quite hard to source in the UK as I only have 14 days to decide whether to keep the Icon.


----------



## smial1966

khaine1711
   
  Congratulations on your purchase and I hope that you decide to keep it. You're right in stating that the supplied valves are rubbish, so bang in some NOS Mullards instead. Steve from http://www.mullardmagic.co.uk/mullard/default.aspx has a large stock and is a nice guy to deal with, so search his website and email him if what you're after isn't listed, as he can normally acquire most NOS valves. 
   
  Cheers,
  Andy. 
   
  Quote: 





khaine1711 said:


> Pretty much the best sound I heard with the he6. It makes me stop bugging dealers for demo speaker amp
> 
> 
> 
> ...


----------



## khaine1711

Thanks for the recommendation Andy! He does have some nicely priced Mullard.
   
  I'm still waiting for Icon's response about using 5751 instead of the 12ax7, and 7n7 (with adapter) instead of 6sn7. Quite safe substitution in most cases, but I don't wanna risk anything. Wonder if anyone has tried this?


----------



## alvin sawdust

Quote: 





khaine1711 said:


> Pretty much the best sound I heard with the he6. It makes me stop bugging dealers for demo speaker amp
> 
> 
> 
> ...


 
  Shame the Copland has to go especially when you really like it so much. They have always, to my eyes, made beautiful gear. Before moving into computer audio I lusted for one of the older Copland cd players with the VRDS transport. Anyway sorry for going OT.
   
  Does the HP8 have sufficient juice for the HE6?


----------



## project86

I'd like to hear it from the horses mouth, but I suspect the HE-6 is probably being underpowered by the HP8. Probably gets decently loud but doesn't have the same level of drive and control as with the big amp. Just guessing though.
   
  And I have to disagree with you all about the stock tubes being terrible. They aren't amazing, but I've heard far worse.


----------



## khaine1711

alvin sawdust said:


> Shame the Copland has to go especially when you really like it so much. They have always, to my eyes, made beautiful gear. Before moving into computer audio I lusted for one of the older Copland cd players with the VRDS transport. Anyway sorry for going OT.
> 
> Does the HP8 have sufficient juice for the HE6?




I'm a fan of Copland gear too, and Danish stuff in general. Hopefully a few years into the future, I can afford a s/h Copland 506 and the matching preamp.

I've heard from Icon today, and they call the current HP8 Mk2.2; which is the same as the MkII, just different look together with the stereo/mono and the loop out. Didn't get approval on using 5751 and 7n7 though =p.

The stock valve isnt as bad as some Chinese gears - Mingda and Darkvoice comes to mind; but then it still hinders the Hp8 a lot - and I think they will sell a lot better if one was to put in some NOS valves (hopefully) for the demo unit at their HQ. With the stock valve, the sound is kinda tense and flat/congested. Also there's some weird tonal issue with piano. I've put in a few 12AX7 (left over from the Copland) and it becomes much better. Still waiting for some NOS 6SN7 to arrive though, quite hard to source them locally here in a timely manner. 

About the He6, with a standard 2.5V rms source, my comfortable listening position is around 9-11 o'clock for rock/metal, and slightly higher for classical/dsd. If I change the source voltage to 1.25, I'll need to crank up quite a bit. Hard to say about the "juice" part, ime the hd800 and the he6 scale pretty high, so it depends on what is the best amp you've tried/heard. At least the Hp8 doesn't clip/distort on some difficult classical stuff that I usually listen to. Of course it can't really compete with the Copland, or a few other speaker amp that I've used, but it's quite formidable that this tiny amp doesn't clip.

I'm curious on how it fares against similar priced amp though, in particular the Little dot mkvi; quite tempting to grab the one in classified to compare.


----------



## project86

Soren Mac Larsen, chief designer of some of my favorite Copland gear, is now designing for Lead Audio/Northern Fidelity. I've got a nifty DAC/headphone amp of theirs in for review, and it seems promising so far. 
   
  I'm glad to hear Icon threw in a loop out. Makes the devices more versatile, and easier to integrate into some systems. Good call.


----------



## Xcalibur255

I officially have an HP8 on order with Music Direct.  Hopefully some more people will follow soon.
   
  I have something else in the wings amp-wise that's coming soon as well, but I wanted to make use of my 6SN7 collection and this seemed like a great way to do it.  All of my other new/existing amps don't use this tube now.
   
  I pinged Icon with a few fairly technical questions and ended up having them forwarded to David Shaw himself to answer.  On a Sunday no less.    Great guy all around.  He told me he sees no problem using the 5751 in the amp even though it isn't "officially" approved by Icon.  The only point of concern I had was a slightly higher heater current draw vs. the 12AX7 and David assured me it wouldn't be a problem.  So owners wanting to try out the 5751 should be able to do so without concern.
   
  I'm looking forward to getting the amp.


----------



## khaine1711

Quote: 





xcalibur255 said:


> I officially have an HP8 on order with Music Direct.  Hopefully some more people will follow soon.
> 
> I have something else in the wings amp-wise that's coming soon as well, but I wanted to make use of my 6SN7 collection and this seemed like a great way to do it.  All of my other new/existing amps don't use this tube now.
> 
> ...


 
  Weird, I usually get a salesman who advised against anything but the stock 6SN7 + Ecc83. That said I've been using 5751 in the Icon for a while now without prior approval. I heard from someone in Spain that you can actually use 12AU7/ECC82 too.


----------



## Xcalibur255

The regular support staff did tell me not to use the 5751 as it is untested by them, but I sent some followup questions that were quite technical in nature so they put me in touch with David directly who told me the tube would not be an issue for the amp.
   
  The 12AU7 should be safe too, but the plate resistance is different on that tube.  The 5751 and 12AU7 have the same gain, but overall the 5751 is closer electrically to a 12AX7 (particularly in plate resistance) so it makes for the better 12AX7 substitute.
   
  When I get mine my intention is to run the 5751 primarily.


----------



## khaine1711

Quote: 





xcalibur255 said:


> The regular support staff did tell me not to use the 5751 as it is untested by them, but I sent some followup questions that were quite technical in nature so they put me in touch with David directly who told me the tube would not be an issue for the amp.
> 
> The 12AU7 should be safe too, but the plate resistance is different on that tube.  The 5751 and 12AU7 have the same gain, but overall the 5751 is closer electrically to a 12AX7 (particularly in plate resistance) so it makes for the better 12AX7 substitute.
> 
> When I get mine my intention is to run the 5751 primarily.


 
  5751 can be used safely, otherwise we've probably seen some tranny blown report from Spain . What 5751 are you intending to use? Syl gold print/GE/Tungsol/Ray? I've been finding sone Tungsol 5751 from the EU without much success.
   

   
   
  I think other "idiot-proof" substitution for 12ax7 are 12AT7 and 12AY7. I won't put any 12au7 in until I got confirmation though.


----------



## project86

Man I love that new top plate. Looks so nice, and unique! Mine is boring by comparison but sure sounds good. Just used it with LCD-2 and remembered how great of an amp it really is. Need to try some more tubes soon.


----------



## smial1966

Thanks very much for sharing this information as it gives HP8 owners another tube rolling option. 
   
  Cheers,
  Andy.
   
  Quote: 





xcalibur255 said:


> The regular support staff did tell me not to use the 5751 as it is untested by them, but I sent some followup questions that were quite technical in nature so they put me in touch with David directly who told me the tube would not be an issue for the amp.
> 
> The 12AU7 should be safe too, but the plate resistance is different on that tube.  The 5751 and 12AU7 have the same gain, but overall the 5751 is closer electrically to a 12AX7 (particularly in plate resistance) so it makes for the better 12AX7 substitute.
> 
> When I get mine my intention is to run the 5751 primarily.


----------



## Painterspal

Great to drop back in and see that this thread has moved on a bit and some more listeners have discovered the delights of this excellent amp. I'm still very happy with mine - so content with my current rig in fact that I haven't even been thinking about further purchases. My favourite tube combination has settled down too: Mullard MC-1 and a pair of Full Music 6SN7. Expensive, yes, but more than worth it IMO, it's sublime with my HD800, and makes the HP8 sound better than I ever imagined it could.
   
  By the way, apologies to anyone waiting for the review I promised way back in March (unlikely!). It's 90% ready but real life kind of intervened and I had to put it on the back burner for a while. Things are sorted now and I'll try and get it done.


----------



## Painterspal

Happy days...


----------



## khaine1711

Quote: 





painterspal said:


> Happy days...


 
  Hmmm the led looks ultra bright lol - much brighter than mine at least.
   
  I got the same Mullard (MC1), but the glass is smokier so it doesn't shine as brightly as yours. Got mine for cheap though - no where near expensive as the top rca 12ax7 black plate or the amperex. Still I prefer 5751 in both my speaker amp and the Icon though. 
   
  Did you try any NOS 6SN7 with the Icon?


----------



## Xcalibur255

Quote: 





khaine1711 said:


> 5751 can be used safely, otherwise we've probably seen some tranny blown report from Spain . What 5751 are you intending to use? Syl gold print/GE/Tungsol/Ray? I've been finding sone Tungsol 5751 from the EU without much success.
> 
> 
> 
> ...


 
  I am thinking either Sylvania Gold Brand or a Raytheon with the windmill getter.  I used to love tube rolling, but ultimately once you confirm which are the best the rest of the collection sits so I'm cutting right to the chase this time.  I keep reading the RCAs are the best 12AX7 and 5751 tubes but I have never been a fan of their 6SN7s so I'm sticking with Sylvania until I have a good reason not to.
   
  I think having confirmation on the 12AU7 might be wise, it pulls 10mA on the heater where as the 12AX7 and 5751 only pulls 1mA.  Which makes sense seeing as how their plate resistance values are almost 10x apart from each other too.  Neither is a big number but without knowing what the power tranny is rated for it's always better to be safe than sorry.  I'm curious how the radically lower plate resistance of a 12AU7 would affect the amp's bass response, there should be some effect.  Not that I'm some expert on tubes or anything, I'm just floating a "what if" statement here really.
   
  I must be the only person who doesn't like the new top plate.  It looks like an afterthought rather than integrated into the design.  I initially was going to wait for the new version because the loop-out would have been useful, but I ended up finding another solution for that and went for the existing MKII model just so I could avoid that new copper plate.


----------



## khaine1711

Quote: 





xcalibur255 said:


> I am thinking either Sylvania Gold Brand or a Raytheon with the windmill getter.  I used to love tube rolling, but ultimately once you confirm which are the best the rest of the collection sits so I'm cutting right to the chase this time.  I keep reading the RCAs are the best 12AX7 and 5751 tubes but I have never been a fan of their 6SN7s so I'm sticking with Sylvania until I have a good reason not to.
> 
> I think having confirmation on the 12AU7 might be wise, it pulls 10mA on the heater where as the 12AX7 and 5751 only pulls 1mA.  Which makes sense seeing as how their plate resistance values are almost 10x apart from each other too.  Neither is a big number but without knowing what the power tranny is rated for it's always better to be safe than sorry.  I'm curious how the radically lower plate resistance of a 12AU7 would affect the amp's bass response, there should be some effect.  Not that I'm some expert on tubes or anything, I'm just floating a "what if" statement here really.
> 
> I must be the only person who doesn't like the new top plate.  It looks like an afterthought rather than integrated into the design.  I initially was going to wait for the new version because the loop-out would have been useful, but I ended up finding another solution for that and went for the existing MKII model just so I could avoid that new copper plate.


 
  RCA 12AX7 black plate is very very nice (the ones with red print). I had them in my speaker amp - got my top recommendation for p/p. I never had the chance to try RCA 5751 though, but I did have some Rca 12AU7 (called 5814 me think) - also very nice. Worth looking into Madza 5751 or Siemens 5751 if you can find them cheap.
   
  The plate is the new "look" of the (revised) Icon lineup. It started with their speaker amps which btw sound very nice, and look nice too. Part of the reason is idk, maybe to further differentiate themselves from Mingda =p. I think they succeeded - I like the matte paint + copper plate. Only thing I'd change is to move the power button in the front - instead of the useless mono-stereo switch.


----------



## Xcalibur255

I have the official word on the ecc32 and the 12au7 from David. The answer was no for both. More so the ecc32 as it draws too much heater current as I feared. He did not recommend the 12au7 since it is too different electrically for the circuit. The 5751 is okay because it is practically identical to a 12ax7 aside from the lower gain.

 That should help owners narrow down their rolling options at least.


----------



## Painterspal

Quote: 





khaine1711 said:


> Hmmm the led looks ultra bright lol - much brighter than mine at least.
> 
> I got the same Mullard (MC1), but the glass is smokier so it doesn't shine as brightly as yours. Got mine for cheap though - no where near expensive as the top rca 12ax7 black plate or the amperex. Still I prefer 5751 in both my speaker amp and the Icon though.
> 
> Did you try any NOS 6SN7 with the Icon?


 
   
  The apparent brightness is misleading - it's only due to the very long exposure used for the photograph. The led is brighter than the valves but isn't unusually bright. I've tried a couple of NOS 6SN7 but I can't remember off hand which ones - I'm at work.


----------



## Xcalibur255

A quick question for owners:  The power switch on my HP8 is inverted, having it flipped down turns it on and flipping it up turns it off.  Is this normal or did they accidentally install it upside down?  No biggie either way I was just surprised to see the tubes light up when I plugged the power cord in when I thought I had the main power off.
   
  With 5 minutes of both burn-in and warm-up I'm pleased at the potential of the little amp.  It doesn't sound veiled or muddled at hour zero.  The effect of the impedance switch on my 600ohm Beyer 880s is quite pronounced.  I started the amp off with some NOS National Union 6SN7GT blackglass and will slowly work my way through the collection from there.  For now it is running the stock 12AX7 since I haven't been able to source the ones I want yet.  I thought the stock tube was a JJ, but this is an unbranded tube that only says "Made In China" on it so I'm guessing it is a Shuguang like the stock output tubes are.


----------



## khaine1711

Not sure about the power switch since mine got relocated to the side, but judging from the picture on the web of the old MkII - it's the correct direction (down = on, up = off)
   
  Yeah both the stock 12ax7 and 6sn7 are Shuguang. Hmm how is the effect on the beyer? I'm really curious on its effect on high impedance can - but I won't have access to my dt990/600 or hd800 for a while. With orthos it's like a volume boost - which is quite understandable since their FRs generally does not change with output Z


----------



## Xcalibur255

Volume increases considerably going from each step L ---> H with the Beyers too.  This is an oversimplification but basically the sound goes from thin to thick as you move to the higher settings, the midrange picks up more body with each step and the bass gains more weight.  Interestingly enough I found the middle setting the best for highs, both the low and high setting are fairly sibilant right now which I am chalking up to needing break-in until I have reason to believe otherwise.  But the M setting shelves down the treble a bit for some reason.  I actually wish there were a setting between M and H, this would be a good fit for the Beyer DT880-600.  I think in general Icon could have simplified it to Low and High with low targeting 32ohm and high targeting 250ohm.  Assuming the Beyer actually is 600 ohms over a decent frequency range (which it probably isn't) we are technically only getting a 1:1 damping ratio on the high setting.  I didn't really feel the bass to be more "loose" on high though.
   
  Right now my two areas of disappointment are the soundstage which is pretty poor right now, and the fact that I can tell very plainly the circuit has negative feedback.  It just throws a wet blanket on the sound and takes the air and sense of space out of the notes.  This is only my initial impression, I think the soundstage and note separation will improve with more use.  Whatever coupling cap they are using between the 12AX7 and the 6SN7s must be a poly cap too it has that plasticky overtone to it.  Once I have a better feel for how the amp is voiced these coupling caps will probably get changed for some flavor of PIO cap.
   
  I'm going to go out of my way to run it the next few weeks to see how it improves.


----------



## project86

http://www.innerfidelity.com/images/BeyerdynamicDT880600ohm.pdf

The DT880/600 actually maintains a 600 to just over 700 ohm impedance throughout the range. So damping factor should not vary by much. 

There is a small amount of global negative feedback. As always, some people hate it and some find it worthwhile. I have mixed feelings - my ADLabs Svetlana 2 has zero NFB and does indeed have that air and grace between notes. But the Icon has more drive, more guts. So they each have character. Of course, this could be related to other factors aside from NFB. 

Icon does offer the Jensen PIO cap upgrade which may be a worthwhile option to get done right from the start. I don't really hear the plastic you mentioned but I have always liked PIO upgrades and found them worthwhile.


----------



## khaine1711

Similar to what I feel about the impedance switch - unfortunately to me, as the sound getting thicker, the air/ss seems to narrow down, so I just stick with the L setting.
   
  I'm not so sure about the feedback part though - just heard that both feedback and no feedback has their own drawnback, and one isn't exactly superior to another. Some of the very best amp I've heard have neg feedback (manley 300b/stingray/copland), while a few stuff  which boosts no feedback anywhere (*cough* audio-gd *cough*) isn't that special.
   
  You're right about the caps, the stock coupling caps are two tiny poly caps (SCR poly cap, not exactly the best for this type of duty). Still pondering on which cap to replace though. Generally I like Jensen, but they tend to sound a bit "crowded" and might not be the best match with the Icon. Once I decided on a cap I'll report back (will be either Mundorf S/G/O or Jensen, or even Duelund)


----------



## Xcalibur255

You are right about the feedback issue, it is only one component of the larger picture that determines sound.  In my general experience the amps I have had which use negative global feedback just don't have the same sense of openess so I've come to shy away from amps that use it.  Some designs must have feedback in order to work properly, and some amps use it as a crutch to get away with bad design.  Because this is an all triode design I think it would have been possible to design it without any global feedback, but I'm sure David had his reasons for doing so.
   
  My custom OTL amp has no feedback of any kind and it has the most open, transparent and uncolored sound I have ever heard from a headphone amp.  It puts you in front of the microphones, and at a fraction of the cost that most other amps in this league do.  I only mention this so people know my point of reference when talking about the Icon.  At any rate it is far too soon to judge the little amp, and I haven't even tried it with my LCD-2s yet.
   
  At the end of the day the 6SN7 output stage is what drew me to this amp.  I was facing the choice of selling off my collection or finding an amp to use them in and I made my choice.


----------



## Xcalibur255

khaine, can I ask you what the value was on those coupling caps?


----------



## khaine1711

Quote: 





xcalibur255 said:


> khaine, can I ask you what the value was on those coupling caps?


 
  0.33uF; 630VDC; tolerance is 5%. It's the same cap as this one. The one Icon offers as upgrade is Jensen Copper foil  (aluminum can with silver lead out) of the exact value.
   
   

  I heard from a friend who build amp that this particular cap is not usuall for signal/coupling. He also hints at changing the resistors to better ones, but I'm not sure I'm confident enough to replace transistor inside the Icon chassis.
   
  On an unrelated note, have you tried Glenn's OTL with the Hd800?


----------



## Xcalibur255

I haven't tried my own amp with HD800 (don't own them, went for the other end of the spectrum with the LCD-2), but Glenn himself has HD-800's and uses them to check when building his amps.  A number of other owners of his amps report extremely good synergy with both the HD800 and HD650.  This is one of those things that makes me question what I know about things like impedance matching.  Unlike most OTLs his design has an unusually low output imedance, something we were going for deliberately so it could drive phones like Grados or the LCDs well.  With 5998 tubes my own amp has about a 25 ohm output impedance which is pretty great for an OTL design, but in theory this should make it less ideal for phones like my Beyers.  Yet that isn't the case and the synergy between the Beyers and my amp is excellent, and so is the synergy between it and the LCD2s.  Honestly any quality well engineered headphones seem to sound their best on the amp, which makes me wonder why the whole impedance thing is up in arms all the time in the first place. 
   
  Thanks for the info on the caps.  0.33 is not the value I would have expected, but then again I'm still pretty much a novice when it comes down to the details.


----------



## khaine1711

Impedance matching is still preference I guess. I prefer my Beyer 600 ohm from a SS amp (low output Z). I tried adding 120 ohm (IEC standard), or using some high imp (various typical OTL amp) stuff but it didn't work for me. Sennheiser seems to hint at electrical dampening to change the signature in their hdvd600/800 too (43Ohm out I think?)
   
  Thanks for the info on Glenn stuff, I might have to ... acquired one. I'm a fan of good OTL designs (Berning/Atma-sphere/Zana Deux).


----------



## Xcalibur255

FWIW the amp I have isn't made anymore.  He is doing a variation on it now I believe.  I brought about the version I have with the 5998 output, but both Glenn and I have had...... unfortunate things happen to our headphones due to these tubes developing shorts so he decided to move away from them.  He was working on a design using 6336 tubes for high power output that sounds really promising, but that'll be a pretty good size amp and a real room heater.  Of course you could always stick with the 6AS7, but honestly once we did the design mods the amp sounded so much better with the 5998 there was just no going back.  That tube is a sleeper.  People use them in 6AS7 amps not knowing their potential because the 5998 is starved of plate current in a 6AS7 circuit.  If you open it up and "let her buck" so to speak they are incredibly transparent tubes with amazing inner detail and completely liquid and effortless presentation.  Too bad they are so unreliable.  Still I love my amp and wouldn't give it up for anything.  I'm looking forward to having it back.
   
  Anyway, apologies to all for the off-topic chatter.
   
  I've been listening to the Icon for the last hour or so.  It took a big shift in sound about 30 minutes ago, the treble tamed way down and the soundstage let itself out a few belt sizes.  Just the chance I was waiting for.  I love actually listening to amps while they break in, they pretty much all seem to go through the same stages, but sometimes I can literally hear the treble setting down in the space of a single song and I love experiencing that.


----------



## Painterspal

My review is up - here. Hope you enjoy it - go easy on me!
   
  I have some listening impressions based on actual tracks that I'll post at some point. I'll probably add some photos too.


----------



## alvin sawdust

Quote: 





painterspal said:


> My review is up - here. Hope you enjoy it - go easy on me!
> 
> I have some listening impressions based on actual tracks that I'll post at some point. I'll probably add some photos too.


 
  That's a really good read, thanks for taking the time.
  What are your thoughts with it powering the LCD-2s?


----------



## Xcalibur255

I think it's noteworthy that all of the reviews so far have been amps which have the upgraded Jensen PIO coupling caps.  I am beginning to feel this is a very important thing for potential buyers to keep aware of.  The US distribution of this amp by Music Direct is only for the standard version so we can't get ahold of the version with the Jensen caps.  I feel I have enough hours on my amp now to be able to say this cap upgrade makes a pretty significant difference in the performance of this amp.  So far I'm consistently disappointed by how compressed, grainy and unnatural the highs are, and the whole sound in general is thin and edgy with the Beyers.  It sounds smoother with the LCD2's, but there is no transparency or realism to instrument timbres.  This is with some of the best NOS 6SN7 tubes around keep in mind.  I will grant running the stock 12AX7 is a bottleneck that I'm trying to keep aware of in my judgements, but until the new tubes I bought for this position arrive there is nothing I can do. 
   
  What I'm hearing doesn't jive with the reviews, so I'm going to upgrade the coupling caps in my amp and put the theory to the test and find out.


----------



## Painterspal

Quote: 





alvin sawdust said:


> That's a really good read, thanks for taking the time.
> What are your thoughts with it powering the LCD-2s?


 
   
  Thanks - much appreciated. Actually, I thought it was fine with the LCD-2, in my view it drove them well. I can't comment on the sound specifically because I sold them some months ago. Others may want to chime in...


----------



## khaine1711

Well I think a cap change will do far more than any tube rolling - especially to a transformer coupled amp. Good thing is you can replace the caps yourself, and it's much cheaper than what Icon is charging here in the UK (of course it might not be as pretty). One of the reasons I didn't order mine with the cap upgrade.


----------



## Xcalibur255

Quote: 





alvin sawdust said:


> That's a really good read, thanks for taking the time.
> What are your thoughts with it powering the LCD-2s?


 

 It drives them well generally speaking.  There is enough current swing on tap for everything but very loud listening.  It doesn't sound off pace or lacking in dynamics.  The biggest issue is the bass, the lowest octave is pretty MIA probably due to the limitations of such small output transformers.  Bass notes don't seem to carry through with the sense of weight that the LCD-2 is so very good at conveying, the notes feel a bit hollow on the Icon.  The bass control is there, nothing sounds "one note" althought sometimes I feel like it just barely has a grip on that control if you know what I mean.  It doesn't sound dark or overly damped on the high end though, at least not with appropriate tubes.  The LCD-2s are painfully revealing of the amp's lack of inner detail and low level resolution, again I think those coupling caps are the major contributor to this.  A quick upgrade there and a quality driver tube and the amp will make a fine companion for the LCD-2.  I feel the synergy with the amp is actually quite a bit better than with my Beyer DT880s.  The Beyers sound too thin with anything other than the National Unions in the output sockets, but those tubes have quite a few weaknesses of their own so it is a compromise either way.


----------



## Xcalibur255

I've finally got a good tube for the driver socket, a triple mica black plate Sylvania 5751.  This was a major upgrade.  If any owners got their amp with the OEM Shuguang 12AX7 instead of the JJ tube project86 had in his review my advice is to get rid of it ASAP.  It seriously holds this amp back.  I was expecting an improvement when the Sylvania went in but not this much of one.  Gone is the edgy hifi-ish sound and in its place is the open effortless sound I expect from a good tube amp.  I still plan to do something with the coupling caps for curiosity sake but with this change the amp is now pretty nice to listen to.


----------



## Painterspal

Quote: 





xcalibur255 said:


> I've finally got a good tube for the driver socket, a triple mica black plate Sylvania 5751.  This was a major upgrade.  If any owners got their amp with the OEM Shuguang 12AX7 instead of the JJ tube project86 had in his review my advice is to get rid of it ASAP.  It seriously holds this amp back.  I was expecting an improvement when the Sylvania went in but not this much of one.  Gone is the edgy hifi-ish sound and in its place is the open effortless sound I expect from a good tube amp.  I still plan to do something with the coupling caps for curiosity sake but with this change the amp is now pretty nice to listen to.


 
   
  Yes, reinforces my view that a good 12AX7 really makes a big contribution to the sound of this amp.


----------



## project86

Quote: 





painterspal said:


> Yes, reinforces my view that a good 12AX7 really makes a big contribution to the sound of this amp.


 
   
  I'd agree with that. Better to spend some money on upgrading that first rather than the other pair - they matter too, but not as much. 
   
  That said, you still have to spend some money to get a reasonable improvement over the stock 12AX7. I have some basic (new) Mullard and Sovtek and EH and none of them really do a whole lot. My favorite cheap upgrade is the Genalex Gold Lion which can be had for like $40. I also really like the JAN GE long plate which is really nice for under $100.


----------



## mironathetin

I'd like to come back to the hum of the HP8. Is it related to the electric environment or is it an inherent property of the HP8s noise floor?
   
  I remember how the Leben amps were praised. Finally I listened to them at a local dealer and both, the CS300 and the CS600 produced a noticable hum in my HD 650. Since I like to listen at low volumes and also listen to classical a lot, their hum is certainly not tolerable. It completely rules out both Leben amps for me, although they do sound excellent.
   
  That said, my Earmax silver amp is a terrific pairing with the HD 650, but a bit underpowered for the HD 800 and I'd like to find a new tube amp. The Earmax is absolutely free of hum, though. So it seems to be possible to design a tube based circuit without any hum.
   
  Can someone comment on the hum of the HP8, please?


----------



## project86

Quote: 





mironathetin said:


> I'd like to come back to the hum of the HP8. Is it related to the electric environment or is it an inherent property of the HP8s noise floor?
> 
> I remember how the Leben amps were praised. Finally I listened to them at a local dealer and both, the CS300 and the CS600 produced a noticable hum in my HD 650. Since I like to listen at low volumes and also listen to classical a lot, their hum is certainly not tolerable. It completely rules out both Leben amps for me, although they do sound excellent.
> 
> ...


 
   
  On my HP8, it ends up being caused by ground loop issues. I figured that out by feeding it from a battery powered DAP - it was very quiet in that situation. Not completely silent at full blast volume, but very few amps are..... 
   
  I did some tweaking and eventually got the system as quiet with a regular transport as it had been with the battery powered DAP.


----------



## mironathetin

So you would say, even in quieter passages of the music, the noise of the HP8 is not audible?


----------



## project86

Quote: 





mironathetin said:


> So you would say, even in quieter passages of the music, the noise of the HP8 is not audible?


 
   
  Definitely not.


----------



## mironathetin

Quote: 





ozer said:


> ( ... )
> 
> I want to buy a new amp, but the problem is that I don't want to pay import duties, as the import duties is 45% of the price here in Sweden... I have to buy inside EU if I don't want to pay that. It's really hard to find any amps here in EU....
> 
> ...


 
   
  If you use the HD 650, I cannot help to recommend the Earmax Silver. It is the best amp I heard so far with the HD 650, and I listend to many (Earmax Pro, XCan V3 and 8, MF HP1, Black Cube Linear, Leben CS 300 and 600, Violectric (forgot which one) etc.).
   
  I am not pleased enough with the HD 800 / Earmax combination. This may not the the fault of the Earmax though, I don't know. People say, it is underpowered for the HD 800 and that's why the combination is not stellar. But people say the same about the Earmax and the LCD2 and I cannot confirm that at all (see below).
  But from time to time I like to get some ideas how to power the HD800 in a way, that I'll enjoy it as much as my HD 650 with the Earmax.
   
  If you are interested, here are two posts about the Earmax, that I wrote:
  http://www.head-fi.org/t/473691/comparison-lehmann-back-cube-linear-earmax-pro-x-can-v8p-with-hd-650
  http://www.head-fi.org/t/635784/lcd-2-amps-earmax-silver-and-lehmann-black-cube-linear
   
  And a similar post from Jornfin, who happens to have the same amps and headphones, that I use. Very nice review, btw.
  http://www.head-fi.org/t/232635/earmax-pro-over-mf-and-lehmann


----------



## Xcalibur255

I have not experienced any audible hum with either the dt880 or the lcd-2.


----------



## khaine1711

I have a very slight hum with the He-6 - couldn't hear it with music playing but not as dead silent as my other valve gear. The He-6 is so insensitive that it is quite immune to hum/hiss -  this makes me worry a bit since I don't have my other cans here with me to check out (hd800 and dt990/600 mainly).
   
  However with the Dt1350, the hum is very loud. Anyone has portable/iem they wanna try with the Icon?
   
  I'm pondering if I should send it back to Icon for a check-up


----------



## project86

I get some hash type noise with IEMs, which is similar to most other Class A tube amps out there. But I can't imagine the HE-6 is normal. When you say "hum", is it independent of volume level or does it get louder as you turn the knob? Also, have you tried to listen with no interconnects and see if it's there? What about different outlets, in different parts of the house? All things I'd try before sending it back.


----------



## khaine1711

Quote: 





project86 said:


> I get some hash type noise with IEMs, which is similar to most other Class A tube amps out there. But I can't imagine the HE-6 is normal. When you say "hum", is it independent of volume level or does it get louder as you turn the knob? Also, have you tried to listen with no interconnects and see if it's there? What about different outlets, in different parts of the house? All things I'd try before sending it back.


 
  I think it's a transformer hum. It's independent of volume level or whether there's a source plug in or not. It's really faint with the He-6 though, similar to the noise level of a silent (~500rpm ish computer cooling fan).  The only thing that can "increase" the hum is the impedance tap.
   
  Do you get a transformer hum on IEM or just the hash noise (symptom of too high gain)?


----------



## mironathetin

Thanks guys, keep going. This is THE interesting information.
  I don't know what's typical for tube gear in general. My Earmax silver is completely silent as was my X-Can V8 (which is a hybrid).


----------



## Painterspal

When no music is playing and if the house is completely silent I can just faintly hear a hum. It doesn't change with the volume so I assume it's caused by the transformer. Icon Audio actually mention in the information sheet that a slight hum is to be expected and is completely normal. It's slightly louder on the highest output impedance setting but I can't hear it at all during music playback at any setting, even during the quietest pianissimo passages of classical music, so it's a non-issue for me.
   
  Like Project86 I did have problems initially with ground loop hum, but as it's also raised its ugly head with my speaker rig I assume it's more to do with the electrical supply in the house. However, once I cured it all has been fine for me.


----------



## mironathetin

Internet research: 
  Earmax Silver Signal to noise level > 95db, hum, vol. max.: < -85 dB
  Icon Audio HP8 Signal to noise level 90 db
  X-Can V8 Signal to noise level > 100 db
  Leben CS 300 - no info to compare numbers


----------



## Xcalibur255

I have to say the genalex gold lion is the first new production tube I've ever really been impressed with. Very smooth and airy with better staging and imaging than the NOS Sylvania. I think the syl still has it beat on low level detail retrieval but the genalex is still no slouch. Well done, New Sensor.


----------



## tigerkg13

[size=small]Big thank yous to Painterspal, Project86 and Spudharris for helping me in making the decision to order one (the upgraded version). I really appreciate the time they took to reply to my PMs and this helped explain a lot of my queries. The unit is on the way at this very moment! As regards the hum issue this is what Adrian from Icon Audio has to say:[/size]
   
   
   
  [size=small] "This unit has been fully tested  (referring to my unit) and the hum level is normal and only audible at full volume (at which the music would be too loud to listen) and certainly never audible at normal listening levels. Some people use the HP8 MkII near to other units and this can lead to the HP8 MkII picking hum from external sources/magnetic fields such as motors and transformers, or they use extremely sensitive headphones at the same time, so please bear this in mind when you position your HP8 that it is not near to other motors/transformers." [/size]
   
   
   
   
  [size=small]Hope the explanation from Icon Audio helps.[/size]


----------



## khaine1711

That statement from Adrian is a bit inaccurate. The transformer hum always stays at a constant level, and does not get louder when you turn up volume. This is true for most transformer coupled amp. The only thing that increase the hum on the Icon is the impedance tap.
   
  On the L setting, once you turn up the music, you cannot hear the hum. You can still faintly hear it when no music is playing, or the music suddenly goes quiet (think Shostakovich's Leningrad -  Allegretto). But I will agree on the point that it's not audible at normal listening level, and with the majority of the recordings.
   
  That is on the L position though. With the H position, you can hear the hum with say ... a video of someone talking about something on youtube. But then I doubt anyone would specifically need a 600 ohm output Z 
	

	
	
		
		

		
			





.
   
  Did you opt for both the cap upgrade and valve, or just the caps?


----------



## tigerkg13

Sorry, I don't know much about tube amps. but I do believe the upgrade in question refers to the capacitors. Whether the valve is included or not I can't be sure. In one sentence he talks about the capacitors and then refers to it in more detail as follows:
   
   
'The benefit of  having the Jensen copper foil upgrade is that you will get a more “silky smooth” sound reproduction. The cost of this upgrade is and additional 85.00 pounds.'
 
   
I also upgraded the tubes he recommended. The costs of this upgrade is separate. BTW, my unit is the HP8 Mk2 (matte) not the HP8/MP3 version.


----------



## Xcalibur255

Unfortunately for your wallet the amp needs both a driver tube upgrade and a coupling cap upgrade to sound good.  It doesn't have to be Jensens, there are lots of good caps out there that can improve upon the stock choice.  I feel fairly confident that the remaining midrange coloration I'm hearing will go away once I get my new caps in.  Power tubes will improve your sound too, but the driver upgrade over the basic stock Shuguang is essential. 
   
  Not to contradict khaine but rather just to offer my own experience for additional perspective, my own HP8 is silent during operation on all impedance settings.  I haven't gotten a hint of tranny hum and I have yet to pick up any microphonics from tubes either.  I was pleased to discover this evening that my BGRP Tung Sol 6SN7s which are noisy in driver applications work perfectly and noise free in this amp which is just what I was hoping for.
   
  I have some sensitive headphones I can use to further investigate the amp's noise floor, I'll check into this.  I think what it may come down to is build variation, how close certain B+ wiring comes to the power supply and how carefully any shielding is laid out can have a major effect on hum levels.  This can vary from unit to unit because they are mostly hand wired.  I recall from the Woo owner thread somebody who was constantly haunted by hum from his WA22 which is an amp that is usually quiet.  The issue only went away for him when he sent it back to Woo and they basically re-wired it again to prevent the interference that was getting into the B+ (the electricity that carries the actual audio signal) in the first place.


----------



## khaine1711

The noise floor is pretty low. At least in my case it's lower than the hum - which is quite good.
   
  Also nothing contradicting really, could be my unit, or it could be that their 120v trannies are more quiet than the 230V. But to get no hum on high setting, that's amazing. Still, I plan to send it back to Icon to check before I did my own capacitor upgrade. If it still hums I'll just accept that I'm way too anal sensitive about transformer hum in general.
   
  On the tube rolling thingy, I'm also using BGRP 6SN7, but with the Mullard Mc1 in front. Trying to track down some gold brand Sylvania 5751 from the EU with no luck.


----------



## Xcalibur255

There is some consensus that the triple mica black plate 5751 Syl and the Gold Brand are pretty much the same tube sonically.  I just went with what I could find for a reasonable price, the GB tubes get bid sky high.
   
  I'm suspicious there may be something going on with your amp.  I'll try out a few other headphones if it helps, but I've run the LCD-2 and the DT880 on every gain setting and never heard any transformer hum on any of them.  I've found the DT880 sounds best on the High setting now that I have the sibilance tamed, and the LCD-2 of course sounds best on Low. 
   
  I'd been meaning to try the other headphones out anyway since it helps give a better picture of the amp's flexibility. 
   
  The BGRP Tung Sols pair really nicely with the Genalex.  I had some Sylvania bad boys in the output position but this was a little too laid back sounding for the LCD-2s, the Tung Sols are still smooth but sounds better balanced overall.  With this setup I feel the caps in the amp are what is holding things back.  The amp doesn't feel very transparent on some material and I don't believe the tubes are contributing to this.
   
  Just a random thought here, but I really wonder why David didn't just design this amp to run 3 6SN7 tubes?  This amp has way more gain than it needs with the 12AX7, and the distortion and linearity are inferior to the 6SN7 anyway.  I think a lot of designers just automatically use the 12a series mini tubes simply because that's "what you use" in the first stage, them being the most popular tubes in use when tubes originally rode off into the sunset.  I think the amp would be better all around if it were driven entirely by 6SN7s.  Maybe in the MkIII?


----------



## khaine1711

I think all black plate Sylvania 5751 are the same. The one different is grey plate gold pin. 
   
  On the 3x 6SN7  I think it has more to do with availability and expectation. People generally expect valve amp to have those tiny preamp tubes, followed by several big power tubes - then add in some shiny rectifier/glowing phase splitter if possible. An amp running only one type of valve may throw some people off =p. Reminds me of the Super 7, my thoughts process is like what on earth should I do with various sets of seven 6SN7s in case I upgraded.
   
  Also good 6SN7 are rare in the UK, while ecc83 are numerous.
   
  Do you get no audible hum on the lcd2 with all impedance setting (especially High) - even in a dead quiet room with no music playing?


----------



## Xcalibur255

I'll have to check again when the air conditioner isn't running, but I don't recall hearing any.


----------



## khaine1711

Quote: 





xcalibur255 said:


> I'll have to check again when the air conditioner isn't running, but I don't recall hearing any.


 
  Appreciate you taking the time to check it out.
   
  One small request for owners, a bit silly though - could any of you try .... lifting the Icon up and turning it upside down to hear if there's any sound? - like a small sound of a nut/bolt tapping/touching the enclosure. I know it's heavy (7 kg) but if you could do that it would be a big help 
	

	
	
		
		

		
		
	


	



   
  I think I heard a sound similar to a screw coming loose inside the main transformer (the big black box on top) when I turn it upside down for cleaning purposes. Could be the source of the hum I'm experiencing (transformer isn't tightened enough).


----------



## Xcalibur255

Since the wiring is point to point I think the most likely source could be a small bead of solder loose inside the unit.  Sometimes they get under things and are missed during inspection but shake loose during shipping.  Just a guess of course. 
   
  Or another thought:  does it happen after the amp has been on a while?  If so it could be vibration coming from output transformer oscillation, which would be bad.  This shouldn't happen as long as there is a load on the circuit (aka you have headphones plugged into the jack).


----------



## khaine1711

Quote: 





xcalibur255 said:


> Since the wiring is point to point I think the most likely source could be a small bead of solder loose inside the unit.  Sometimes they get under things and are missed during inspection but shake loose during shipping.  Just a guess of course.
> 
> Or another thought:  does it happen after the amp has been on a while?  If so it could be vibration coming from output transformer oscillation, which would be bad.  This shouldn't happen as long as there is a load on the circuit (aka you have headphones plugged into the jack).


 
   
  The hum is constant, from the start up to when I turn it off. Oh well could be anything, could be I'm spoilt by Hashimoto/Tango and the likes 
	

	
	
		
		

		
		
	


	




.
   
  I've sent the Icon back today - with a note hoping they would at the very least check if something is loose inside the main transformer. I also did grab the capacitor upgrade from Icon - might as well be the first to hear both the stock and the SE version (sans the tube upgrade of course). Mundorfs S/G/O and Duelund also on the way, but they gotta sit inside my drawers for several weeks I guess.


----------



## Xcalibur255

Okay I did some checking and timed it so I could have total silence in the room (no running A/C, refrigerator, ect.).  With the LCD-2 I cannot detect any hum or background noise whatsoever at any of the 3 gain settings when no music is playing.  There is just dead silence.  So I grabbed my JVC HARX-900's I usually only use for late night TV watching and repeated.  On the low gain setting there is an incredibly slight amount of hum, at the threshold of being undetectable.  It gets very slightly louder on medium, and a bit louder again on high.  You don't have to strain to hear it on high, the hum is evident, but at a level I still feel is slight and not objectionable at all.  Volume setting has no effect on this, the level is constant.  The JVCs are quite sensitive, they hum loudly on my OTL amp when I'm running 5998 tubes to the point where it is a waste of time to even try listening to music on them that way.  I also noted some static/hiss that increases with volume on the JVCs on high gain.  Slightly more noticeable than the tranny hum was at higher volumes with no music playing.  With the JVCs I can also detect microphonics from the Tung Sols.  A tap on the metal cart the amp sits on produces some slight pinging I already knew these tubes were guilty of when they vibrate.
   
  For clarity sake, I cannot hear any of this whatsoever with music playing, these observations are all with no music being played.
   
  Hopefully this helps.  Some other factors such as the stability of the incoming power and what other gear is feeding the HP8 might have an impact too.


----------



## Xcalibur255

On a side note, the JVCs are pretty listenable on the HP8.  Best sound I have heard from these modest headphones.  I'll have to try my other forgotten/neglected headphones I have lying around.


----------



## Xcalibur255

My HP8 got its cap upgrade today:  NOS Soviet K40Y paper in oil caps.  I wasn't quite prepared for how much bigger they were than the tiny stock caps.  They are at least 6x in size.  It's a good thing the inside of the amp isn't crowded in that area or they would not have fit, as it was they just barely fit in there.
   
  Now the break-in clock gets reset since I know from experience these caps need it.


----------



## khaine1711

Just dropping in to say I got my Icon back today. Turnaround time is ~5 working days. Here's the cap upgrade. Impression compared to stock caps coming soon.
   

   
  Also the rattling sound I mentioned earlier turns out to be the spare fuse in the fuse box. Nothing went loose inside the Icon.
   
  The best part is the unit is completely free of hum now, even on the High setting (with the He-6). Icon said they did replace another capacitor (not the two jensen) to reduce the hum.
   
  Overall I'm happy; especially when I have a (literally) drawer of 5751s heading toward England


----------



## Xcalibur255

We'll have to compare notes. The K40 and the Jensen are supposed to be fairly similar sounding. I was able too get my caps in on each side since they are not as thick as the Jensens. They are longer though so that came with its own challenges.

I'm very pleased with the improvement I got. I actually agree with the positive reviews now. The stock cap was a major bottleneck for sound quality for this amp.


----------



## JamieMcC

Khaine1711 Hi I would be interested to read your Impression of the upgraded caps compared to the stock ones hows the amp sounding?


----------



## khaine1711

I never thought highly of the sonics of the stock Icon. I liked the cosmetic (the copper plate!) but that's it. The amp in its stock form lacks details, and sounds constricted compared to the better amps I have. That is with Tungsol BGRP and some of the best nos 12AX7 .
  
 With the caps upgraded it improved a lot - I'd say better than any tube rolling. It picks up small detail - like very small nuances in live recording better. The sound is more airy, and have a tiny bit of velvety tone - for the lack of better words.
  
 That's the effect of the Jensen caps. I've never heard the one in the Icon before (Jensen yellow aluminum can) - but I've heard its bigger brothers many times (Jensen paper can and copper can). They do add something very seductive and palpable to the human voice - we usually call that "taste the lips" of the singer 
	

	
	
		
		

		
			





 (female of course!).
  
 All in all, if you're buying the Icon, the order of importance to improve the sound would be: Caps -> The 12AX7/ECC83 tube -> The pair of 6SN7.


----------



## PTom

Sorry to resurrect an old thread.
  
 I'm thinking of getting these tube amps. Is it correct to say that it's quite important to request the Jensen caps  upgrade and also valve upgrades (Treasure CV181’s in place of Shuguang 6SN7s’ and a gold pin JJ 12AX7/ECC83) for this amp to sound  really good?


----------



## Spakka

Well I'm perfectly happy with my non-upgraded caps but I have upgraded the tubes (matched pair full music 6SN7, gold lion 12ax7).
 I would imagine the amp would be rather expensive if you upgraded it that much.


----------



## Xcalibur255

It cost me $20 to swap the coupling caps. 
  
 I considered the amp a waste of a thousand bucks before doing that upgrade, now I find it satisfying enough to keep it.  As someone who has had to opportunity to hear the amp both before and after I can't stress enough how badly this amp needs a quality paper in oil cap in place of the cheap Solens that start out in there.  The amp just doesn't have proper tone with the Solens, and the bass was completely devoid of any kind of weight or presence.  I'm honestly quite amazed the K40Y caps made as big of an improvement as they did, it's a very pleasant little amp to listen to now and I feel no temptation to mod or change anything else.
  
 If you are handy with a soldering iron it is a 5 minute job, one I can't recommend enough if you own this amp without the Jensen upgrade.


----------



## Spakka

Hmm maybe I should give that a try then... which caps are the ones that need replacing? (if you have a pic that'd be awesome).


----------



## khaine1711

Since it's p2p wiring, each unit will have slightly different layout - but it's the two 630v  0.33uf solen cap near the Ecc83


----------



## Spakka

Oh whow, those are tiny!
 Hmm seems like a tricky DIY as could be hard to get the space!


----------



## khaine1711

Depends on the cap used, you can easily fit any two caps inside the Icon (aside from the gigantic Duelund of course)


----------



## Spakka

khaine1711 said:


> Depends on the cap used, you can easily fit any two caps inside the Icon (aside from the gigantic Duelund of course)


 
  
 Yes, I have had a look and there is room, I've gone and ordered the required stuff to discharge old caps (and a soldering iron!). Once everything is ready to go I'll start taking pics to log it as it'll be my first DIY. I went for the Jenson caps - found a site selling them for about 1/2 what Icon wanted.


----------



## khaine1711

Icon price is a bit high since it includes labor cost (and they paid for return shipping). For their price, if you can DIY, you can even put Jensen paper cans instead of the copper can


----------



## Spakka

I went for the aluminum cans as those were the cheapest, and the ones offered by icon. I didn't want to spend £160+ on caps!


----------



## khaine1711

Might as well try Mundorf and *cough* Vcap *cough*.
  
 I remember reading some comparisons on caps on the Hp8, and the Vcap TFTF comes out on top (which it should considering the price) =p


----------



## Spakka

Those are... a tad expensive... I'm having to sell my old DAC to fund this anyways!


----------



## Xcalibur255

The Russian K40Y9 I used are every bit as good as the Jensens and costs far less.  They're a cult favorite in oil caps and sound lovely.  Like I mentioned I got my pair for $20 and you should be able to do the same on eBay.  The effect it had on the midrange was exactly what the amp needed.  The weight and body improves a lot. 
  
 They might be 10x bigger than the Solens they replaced but they still fit just fine in my amp, there is actually quite a bit of breathing room on that side of the amp to fit bigger caps.  I meant to take before and after photos when I had the cover off but ended up forgetting to do it once things got started.
  
 Mundorf silver oils would probably suit this amp nicely as well. 
  
 edit:  by the way good choice on the Gold Lion 12AX7 Spakka.  I'm currently running a Sylvania 5751W triple mica black plate to lower the gain a bit, but the Gold Lion has it beat in resolution and balance which is impressive for a new production tube.  That tube and a nice pair of NOS Sylvania 6SN7 is a good setup for the amp.


----------



## Spakka

So, I have a quick question now I have the capacitors (delivered rather quickly!)...
  
 I have the Jensen ones and they suggest placing them so that the outer foil is closest to the grounded side of the circuit (the output stage?) and the inner foil is closest to the positive side - I think this means the inner foil (which is marked by the black line on the cap) should be connected to the 6SN7, and the unmarked outer side to the 12AX7.
  
 Is this correct?
  
  
  
  
  
 Edit: This appears to be the case from the pictures posted in the thread, but it's not 100% clear as pics blurry/small.


----------



## Spakka

So I have inserted the new caps... 
  
 And, whilst I obviously can't A/B, I was feeling very cynical that I would be able to hear any difference... There definitely is a reasonably sized improvement - Bass is certainly improved, and I'm fairly sure that the higher end is a tad clearer. Of course it's hard to tell with certainty, but overall seems like an improvement well worth the cost!


----------



## Xcalibur255

The caps are new.  Run the amp as much as possible and put about 100 hours on the new parts, then listen again.  You'll be impressed all over again.


----------



## lithium1085

It seems that Icon audio has gone ahead and updated the HP8 with custom CV181 tubes.
  
 http://www.musicdirect.com/p-164284-icon-audio-hp8-mkii-cv181-triode-tube-headphone-amp.aspx
  
  
 I also had a question about the MP3 amplifier. Has anyone tried them with high sensitivity circumaural headphones ?


----------



## PTom

audioaffair.co.uk told me that Icon Audio are updating the HP8 MKII so I contacted Icon Audio directly regarding the specific upgrades and received the following reply:
  
 "The new version has some circuit improvements, improved cosmetics and a “loop through” facility for those with limited inputs/outputs."
  
 They also mentioned that they have a more expensive signature edition with Jensen caps and valve upgrades.


----------



## lithium1085

ptom said:


> audioaffair.co.uk told me that Icon Audio are updating the HP8 MKII so I contacted Icon Audio directly regarding the specific upgrades and received the following reply:
> 
> "The new version has some circuit improvements, improved cosmetics and a “loop through” facility for those with limited inputs/outputs."
> 
> They also mentioned that they have a more expensive signature edition with Jensen caps and valve upgrades.


 
 hmm.. So there will still be a 6SN7 version available? I am not sure if I interpreted that correctly...


----------



## PTom

I think so, the specs on their website seems to indicate that they are using 6SN7 valves. 
 http://www.iconaudio.com/portfolio-item/icon-audio-hp8-mkii/


----------



## PTom

I'm not sure what exactly he meant when he said that the upgraded version had "some circuital improvements".


----------



## khaine1711

ptom said:


> I'm not sure what exactly he meant when he said that the upgraded version had "some circuital improvements".


 
 It's actually out for quite a while. The one on Icon site is still the old Hp8 mkII (which project86 reviewed) with the power switch on front. The "new" version have the power button on the side, stereo/mono switch on the front and revised impedance setting.  
  
 I didn't keep that email last year but I recall Icon calling that version the Hp8 Mk2.2


----------



## lithium1085

khaine1711 said:


> It's actually out for quite a while. The one on Icon site is still the old Hp8 mkII (which project86 reviewed) with the power switch on front. The "new" version have the power button on the side, stereo/mono switch on the front and revised impedance setting.
> 
> I didn't keep that email last year but I recall Icon calling that version the Hp8 Mk2.2


 
  
 Thanks for the info. What exactly have they revised in the impedance settings?


----------



## khaine1711

I need to dig up the manual again but it was a very minor change I think the mid setting goes down from 300 ohm to 250 ohm. Will confirm back later. Also I forgot to mention the Mk2.2 got slightly better volume pot than the MkII.
  
 Anyway if you order after  I think June last year, you'll always get the Mk2.2 (with the copper plate). Was quite surprised myself when I received mine and it looks nothing like the picture .
  
 On another note, the US site (musicdirect) is slightly strange. Me and Excalibur have both emailed Icon and was told not to use the Cv 181 in place of the 6sn7. You can only use the Shuguang Cv181 which is technically a 6SN7, but all other "real" Cv181 can't be used.


----------



## lithium1085

khaine1711 said:


> I need to dig up the manual again but it was a very minor change I think the mid setting goes down from 300 ohm to 250 ohm. Will confirm back later. Also I forgot to mention the Mk2.2 got slightly better volume pot than the MkII.
> 
> Anyway if you order after  I think June last year, you'll always get the Mk2.2 (with the copper plate). Was quite surprised myself when I received mine and it looks nothing like the picture .
> 
> On another note, the US site (musicdirect) is slightly strange. Me and Excalibur have both emailed Icon and was told not to use the Cv 181 in place of the 6sn7. You can only use the Shuguang Cv181 which is technically a 6SN7, but all other "real" Cv181 can't be used.


 
 If you look at the musicdirect picture closely, the CV181 tube is labelled as David Shaw. I believe based on their new brochure for 2014 that these are custom CV181s made to order for Icon.


----------



## Xcalibur255

They are likely having Shuguang make a customized version for them.  Or possibly TJ, which would be better actually as the Full Music are decent tubes.  Seems like marketing to me, the bigger glass looks cooler to most people. 
  
 Electrically it is a 6SN7, a true vintage CV181 valve draws 50% more heater current and would fry the amp.  Shuguang uses this glass style and calls their Treasure series a CV181 as a marketing ploy.  They are nice 6SN7s, but that is what they are:  6SN7s.  Personally my suggestion to new owners of this amp is to grab a pair of Sylvania 6SN7GTB wedge plates for around $25 and go from there.  The new production tubes are very expensive for the performance they offer.


----------



## khaine1711

I agree, cheap pair of NOS Sylvania 6SN7 and a GE 5751/12ax7 Gold lion gotta be the best bang for bucks rolling option for this amp. Might as well stop there and not thinking about BGRP and Osram and other exorbitant 6SN7s haha.


----------



## Xcalibur255

The Gold Lion coaxes the best resolution out of the amp for sure, it actually beats NOS tubes and sounds very linear too.  I have stuck with my Sylvania 5751 because it lowers the gain enough to make the transformer hum completely inaudible for me.  That the Gold Lion sounds more resolving despite the higher noise floor is really saying something.
  
 I do think the amp gains something with the more "famous" 6SN7s in place, but diminishing returns kicks in pretty strongly so it's only really practical for people like you and me who had an existing collection to throw at the amp.  The cap upgrade made tube rolling more satisfying, changes in tone and presentation were a lot easier to detect afterwards.
  
 I've been meaning to put the Tung Sol BGRP back in, my hunch is they'll mesh very well with the K712.


----------



## wgkwgk

I've been following this thread, which has been immensely helpful.  I'm very interested in the HP8 Mk2 (or .2 I guess).  Tubes are the way I want to go.  Question: My DAC/amp is an AUNE T1 which is a great value, has a tube buffer and a very marginal amp.  (I now have an Asgard 2 as the amp.)  Are my priorities in the right order by getting a high-end amp and using the Aune T1 DAC?  Headphones: HD600, HE-500, W1000x, Rs1, and HF2. 
 Thanks!


----------



## sealykojac

I've been debating the HP8 or the WA6SE but I'm thinking I'm going to go for the Icon. I've got some NOS 12ax7s from a previous amp laying around I can test out.


----------



## donlin

I had the original version of the Icon for a while and have recently gotten the current version.  Although I didn't have them at the same time to compare directly, the new version sure seems to sound better and definitely looks a lot better.  I just got one of the new current production Telefunken 12ax7's and it really sounds good.  This amp works particularly well with my LCD-3's.


----------



## sealykojac

I'll be using he-500s with it which I believe should be a good match as well


----------



## sealykojac

gotta love overnight shipping..


----------



## donlin

sealykojac said:


> gotta love overnight shipping..


 
 It's amazingly well built, especially considering the price.


----------



## Poladise

donlin said:


> I had the original version of the Icon for a while and have recently gotten the current version.  Although I didn't have them at the same time to compare directly, the new version sure seems to sound better and definitely looks a lot better.  I just got one of the new current production Telefunken 12ax7's and it really sounds good.  This amp works particularly well with my LCD-3's.


 
  
 How does it compare to the BHA1?


----------



## donlin

poladise said:


> How does it compare to the BHA1?



It's very much the typical differences between tubes and solid state. The icon is definitely warmer in the midrange and easier to listen to on top. The Bryston has a little more resolution and tightness in the bass but seems less musical. I go back and forth a lot so it's a fun pair of amps to contrast.


----------



## sealykojac

I've put about 5 hours on my hp8 today and must say that I love it. I settled on medium output, replaced the stock12ax7 with a nos Ates ecc83 and its sounds great.


----------



## Blueshound24

Sorry if it has been mentioned before, but is there a list somewhere of all the compatible 6sn7's _*specifically*_ with the HP8? i.e. Russian 6H8C, 12sn7, CV1988, etc, etc, etc.
  
 I am aware of the 6sn7 Identification and Reference threads, however I am concerned some may not work specifically with the HP8.
  
 Also, has anyone found _the_ magical sounding tube compliment of 6sn7 + 12ax7 that works well with the LCD 2.2f?
  
 TIA


----------



## Bonesy Jonesy

Hi All,
 Has anybody compared the HP8 Mk2 or current MK2.2 with Woo Audio amps i.e. the WA3, WA6, WA6SE and WA22 ?


----------



## project86

bonesy jonesy said:


> Hi All,
> Has anybody compared the HP8 Mk2 or current MK2.2 with Woo Audio amps i.e. the WA3, WA6, WA6SE and WA22 ?


 
  
  
 I like the WA3 as a fun, sweet sounding amp. I also like the basic WA6, it's solid for the price. I'd say once you go up to the WA6SE the value does not correspond to the price increase. The WA22 is good as well but again too much for what it is. Personally I would take the Icon over all of them based on design, value, and sound. On pure sound quality alone the WA22 is competitive if we don't consider price comparisons. 
  
 The Woo stuff has excellent build quality and looks nicer than my Icon. The newer Icon version with that copper plate is pretty unique looking though, so maybe they are equal at that point.


----------



## Sadkmf

project86,
 Would you consider Hp8 an upgrade over Yulong A18 for HD800 ? 
 mostly for impact and soundstage depth..
  
 Thanx.


----------



## project86

sadkmf said:


> project86,
> Would you consider Hp8 an upgrade over Yulong A18 for HD800 ?
> mostly for impact and soundstage depth..
> 
> Thanx.


 
  
  
 Depends on your preferences. In this case the SS amp (A18) has the more stereotypical "tube" sound to it - warmer, smoother, more bass bloom. The Icon has a sweeter top end though, and can also be fairly warm if you turn up the output impedance knob. Soundstage depth is in fact a benefit of the Icon as well, though tube choice plays a large factor in that.


----------



## Sadkmf

Thanks..
 I got the A18, the problem is I crave more impact especially for rock and electronic..
 If a tube amp can't give me that, I will have to spend the money for a complementary headphone like He-560 or LCD2


----------



## Bonesy Jonesy

project86 said:


> I like the WA3 as a fun, sweet sounding amp. I also like the basic WA6, it's solid for the price. I'd say once you go up to the WA6SE the value does not correspond to the price increase. The WA22 is good as well but again too much for what it is. Personally I would take the Icon over all of them based on design, value, and sound. On pure sound quality alone the WA22 is competitive if we don't consider price comparisons.
> 
> The Woo stuff has excellent build quality and looks nicer than my Icon. The newer Icon version with that copper plate is pretty unique looking though, so maybe they are equal at that point.


 

 Thank you project86 for your post.   Much appreciated.


----------



## project86

To a large degree that's a property of the headphone itself. I'm thinking the A18 is already on the dynamic side and you probably won't get what you are after by switching amps. I'd try to audition an LCD and go from there.


----------



## Sadkmf

Got it...thanks a lot.
 That lack of bass of HD800 is a shame actually, for a headphone that gets 95% of everything right..It's 5% short of being an excellent all arounder..


----------



## Xcalibur255

bonesy jonesy said:


> Hi All,
> Has anybody compared the HP8 Mk2 or current MK2.2 with Woo Audio amps i.e. the WA3, WA6, WA6SE and WA22 ?


 

 I have owned a WA6 in the past.  At one point running it with tubes that cost more than the amp itself did (black glass Tung-Sol 6SN7 via adapters and EML 274B meshplate rectifier) so I've heard the best the WA6 can offer without modding.
  
 The HP8 is a solid step up overall, not a big leap, but there are clear improvements in low level detail resolution, imaging and overall balance.  The HP8 is a good deal less gainy at the top end too.  One thing to keep in mind is my HP8 has been modded with vintage PIO coupling caps.  A stock HP8 with no cap upgrade is barely superior to the WA6, and in terms of tone and bass impact I would even rate it inferior.  The stock Solen interstage coupling caps in the HP8 are terrible and the amps greatest weakness, put there deliberately to help sell the Jensen cap ugprade if you ask me.
  
 These comments are with the HP8 running the very same black glass Tung-Sol 6SN7s that were once in the WA6, along with a Genalex 12AX7 (hands down the best driver tube for this amp in my opinion).


----------



## Bonesy Jonesy

xcalibur255 said:


> I have owned a WA6 in the past.  At one point running it with tubes that cost more than the amp itself did (black glass Tung-Sol 6SN7 via adapters and EML 274B meshplate rectifier) so I've heard the best the WA6 can offer without modding.
> 
> The HP8 is a solid step up overall, not a big leap, but there are clear improvements in low level detail resolution, imaging and overall balance.  The HP8 is a good deal less gainy at the top end too.  One thing to keep in mind is my HP8 has been modded with vintage PIO coupling caps.  A stock HP8 with no cap upgrade is barely superior to the WA6, and in terms of tone and bass impact I would even rate it inferior.  The stock Solen interstage coupling caps in the HP8 are terrible and the amps greatest weakness, put there deliberately to help sell the Jensen cap ugprade if you ask me.
> 
> These comments are with the HP8 running the very same black glass Tung-Sol 6SN7s that were once in the WA6, along with a Genalex 12AX7 (hands down the best driver tube for this amp in my opinion).


 

 Thank you Xcalibur255 for your posting.   Most informative.   Much appreciated.    
  
 How much did it cost to upgrade to vintage PIO coupling caps ?    Did you fit them yourself ?


----------



## Xcalibur255

bonesy jonesy said:


> Thank you Xcalibur255 for your posting.   Most informative.   Much appreciated.
> 
> How much did it cost to upgrade to vintage PIO coupling caps ?    Did you fit them yourself ?


 
  
 Yes, the interstage caps are easy to access in this amp.  If you have any soldering experience the job is very simple.
  
 You can technically put any 0.33uF 630V rated cap in there you want, but I like the NOS Soviet K40Y9 PIO caps very much.  Wonderful tone.  You can find them for $20 or so online and they walk all over much more expensive boutique audiophile caps at that price.  I prefer them to the Jensens actually, although the two are more similar than different in presentation.


----------



## Bonesy Jonesy

xcalibur255 said:


> Yes, the interstage caps are easy to access in this amp.  If you have any soldering experience the job is very simple.
> 
> You can technically put any 0.33uF 630V rated cap in there you want, but I like the NOS Soviet K40Y9 PIO caps very much.  Wonderful tone.  You can find them for $20 or so online and they walk all over much more expensive boutique audiophile caps at that price.  I prefer them to the Jensens actually, although the two are more similar than different in presentation.


 
 Thank you Xcalibur255.  Much appreciated.


----------



## breizh

Hi,
  
 Just got the Icon this week
 I bought it to pair with my Beyer T1 and I can say that it's a wonderful combination
 My Teac HA-501 struggles to feed the T1, while it's very good with AKG K550 and Fidelio X2 low impedance headphones
 I previously owned a Schiit Asgard that was quite good with the T1, enough power but lack of clarity, transparency
  
 With the Icon, everything is on top ! the music is super vibrant, airy, full bodied, providing sparkling treble, great full bass, and marvellous midrange (the voices, the guitars !!!)
 Actually I'm discovering the fantastic skills of the T1 with this one
 It provides plenty of power in the T1's 600 ohms, in comparison with the Teac on which I have to crank up the volume knob really high
 It's also very very good with the AKG and X2, using low impedance positions of the switch
  
 But really a magical pairing with the T1 (either with rock'n roll or classical music), don't hesitate if you're looking for a great amp for the Beyer Flagship !
  
 richard


----------



## scriabinist

Thanks Richard. Which version with the amp did you get? The one with the power switch at the front (older) or on the side (newer)? Which tubes are you rolling? Thanks.


----------



## breizh

Hi scriabinist,
  
 i got the newer version with  the power switch on the side
 the 2 x 6SN7 are new Tung-sol GTB made in Russia, and the other tube is a JJ ECC83S
  
 note that it's not the more expensive SE version with upgraded tubes and caps ! it's the regular one
  
 Richard


----------



## shultzee

I have recently purchased the Hp8 MK11 and am super happy with it.  I just never was totally happy with the Wa6se I owned but so far the icon sounds amazing.   Trying to figure out what the very best tube options would be.  Anyone have any experience with the Shuguang Treasure CV181-z ?  Or any other recomendations?  Thanks


----------



## MP1968

shultzee said:


> I have recently purchased the Hp8 MK11 and am super happy with it.  I just never was totally happy with the Wa6se I owned but so far the icon sounds amazing.   Trying to figure out what the very best tube options would be.  Anyone have any experience with the Shuguang Treasure CV181-z ?  Or any other recomendations?  Thanks


 
  
 I'm very interested to know how you think the HP8 mkii compares with the WA6 SE?
  
 I had the Icon a couple of years ago, and really liked it with one exception: there was a little bit of audible background noise.  I tried changing tubes but never managed to get it to have a totally silent / black background.  So I switched to solid state.
  
 However, it's one of those selling decisions which I came to regret.  I recall that the Icon sounded excellent and the solid state amps I tried never really did it for me (e.g. Phonitor).  A couple of months ago I bought a 2nd hand WA6SE, and have been impressed by both the build quality and the completely silent background.  Plus it sounds good.  
  
 Because head fi is a never ending journey I'm tempted to try the Icon again (I'd ask Icon to upgrade the caps), partly because it's a British company and hence to UK buyers probably offers better value to Woo.   And as I say I recall that it sounded great.  From memory my favourite tube pairing was the Mullard MC-1 with Psvane T series mk 2 6SN7s.


----------



## shultzee

mp1968 said:


> shultzee said:
> 
> 
> > I have recently purchased the Hp8 MK11 and am super happy with it.  I just never was totally happy with the Wa6se I owned but so far the icon sounds amazing.   Trying to figure out what the very best tube options would be.  Anyone have any experience with the Shuguang Treasure CV181-z ?  Or any other recomendations?  Thanks
> ...


 

 I was actually surprised when I read this thread and saw some people had a background noise with the HP8 . I just retested mine and am hearing nothing at all.   I don't know how to explain my experience with the Wa6se.  I just never was totally happy with the sound and ended up chasing a bunch of different tubes. It just seemed a little muddy to me.  I ended up selling it and purchasing a SS amp like you.  At that time I was using a X -Sabre dac and with the HP8 I am using the Stealth DC-1,  so its not a direct comparison.  The HP8 so far is very pleasing although I probably have less than twenty hours on it.


----------



## MP1968

The slight noise I had may have just been a valve issue, rather than the amp itself.  
  
You asked about the Shuguang Treasures.  I had the CV181/6SN7 Premium Treasure Series at the same time as the Psvane ones I've mentioned above, and again they are very good valves.  This is a couple of years ago and I'm relying on my lousy memory, but I seem to recall that there are two different types of these Shuguangs which are exported out of China.  I specifically bought the 'Export Premium' versions which apparently are better quality (I really don't recall why).  
  
Apart from the mC1, the other 12AX7 / ECC83 I liked was the Sylvania 5751 triple mica with black plates.  I this I contacted Icon about this one, and understand that the 5751 has a gain of 70% of 12ax7 but can be used anywhere that a 12ax7 is used.  
  
Hope this helps.


----------



## shultzee

mp1968 said:


> The slight noise I had may have just been a valve issue, rather than the amp itself.
> 
> You asked about the Shuguang Treasures.  I had the CV181/6SN7 Premium Treasure Series at the same time as the Psvane ones I've mentioned above, and again they are very good valves.  This is a couple of years ago and I'm relying on my lousy memory, but I seem to recall that there are two different types of these Shuguangs which are exported out of China.  I specifically bought the 'Export Premium' versions which apparently are better quality (I really don't recall why).
> 
> ...


 

 I am thrilled with the fact that I am liking the Icon straight out of the box.  However , I know eventually upgradeitis will get the best of me.  I really appreciate your suggestions above. Thanks!


----------



## Xcalibur255

If your headphones are very sensitive you may hear some power transformer hum in the Icon.  Other than that noise is more likely to come from tubes.  The driver stage in particular is the place to control it.  A 5751 can help by lowering gain (which the amp has too much of anyway), but good new production tubes like the Genalex generally are quieter than NOS tubes as well.
  
 I've found you can get away with 6SN7s that have a bit of noise or microphony in the Icon as long as its not too bad.


----------



## Bonesy Jonesy

Hi all,
 Can anybody tell me if the older model SE (Special Edition) version of the HP8 MKII with upgraded parts is better than the new standard off the shelf HP8 i.e. no upgraded parts ?


----------



## MP1968

I assume the issue with the new version, off the shelf, is that the stock capacitors are still going to limit performance. From what I've read today on this thread, upgrading to the Jensen capacitors is a very good idea (Icon's optional extra), and presumably still applies to the current version with the new top plate.


----------



## MP1968

I don't know if any UK-based folk can help  (e.g. khaine1711), but I wondered if there's anywhere in this country which would replace the caps on an HP8 for me?
  
I'm highly interested in comparing an HP8 with my WA6 SE.  The only cap upgrade which Icon offers is the Jensen one, at a cost of £102 at the time the amp is ordered.
 
I know from hificollective.co.uk that the retail price for these caps (£24) is around half of what Icon charges for them (although I do appreciate that there is labour in their total charge as well).  
 
Nonetheless, if I'm going to upgrade the caps then why not go further and put in (for example) Mundorf mCap Silver Gold Oil (I assume 0.33 uF / 1000V would be the most relevant).  Or the Jensens in a paper can (more expensive, I know). 
 
However, I've never used a soldering iron before, and so don't think that I have the skills to be able to do the work myself.  I'd be too concerned about making a complete mess of it. 
 
I don't suppose anyone knows anyone who would do this in the UK by mail order, or even better someone based in Essex?
 
Or perhaps this is all a bit over the top.........


----------



## Rapid7

Had my HP8 MK2 for a few weeks now and loving it so far 
  
 Looking at some pictures of the copper top version in this thread mine seems a lot wider and no longer has the over bright blue led light but a purple one which is no where near as bright as the old style blue led.


----------



## Xcalibur255

Mine is also purple, but IMO it is definitely bright still.


----------



## naimless

I think the case is the same size just matt finish on the newer ones with the copper top plate,wish the on/off switch was on the front though,does anyone use the stereo/mono switch?


----------



## Rapid7

Quote: 





naimless said:


> I think the case is the same size just matt finish on the newer ones with the copper top plate,wish the on/off switch was on the front though,does anyone use the stereo/mono switch?


 

 Here is picture of mine, as you can see it's wider notice how the very front tube is set further back and the gap between the 2 rear tubes is also larger. So it looks like this a newer revision of the HP8 MK2 ? compare it against the last picture in post 139.


----------



## shultzee

Looks the same as my new one.  However mine came with different tubes unless you changed them out.


----------



## project86

I was thinking "this guy's crazy" but after comparing those two pics...... I think you're on to something. Can anyone measure and post results?


----------



## naimless

I think it's an optical illusion ,the small 6sn7 tubes in his make it look larger,mine has the David Shaw cv181 tubes and it looks smaller but as far as I can tell the case size is the same.i also think the copper plate makes the newer versions look wider than the gloss black ones although I could be wrong about that as I've only seen pictures of the older versions.


----------



## Rapid7

Right here we go:
  
 First off the copper plate is width 140mm, length is 154mm
  
 Length of the unit including the front & rear alloy plates is 273mm
  
 The width of the front face plate & rear plate is 160mm
  
 Hope this helps.


----------



## naimless

Mine is different
Copper plate 120mm (w) x125mm (L)
Length of the case 252mm
Width of front and rear plates 140 mm
So you were right, Icon have changed the case sizes on the newer amps


----------



## Bonesy Jonesy

naimless said:


> Mine is different
> Copper plate 120mm (w) x125mm (L)
> Length of the case 252mm
> Width of front and rear plates 140 mm
> So you were right, Icon have changed the case sizes on the newer amps


 
 Anybody know why Icon have changed the size ?


----------



## shultzee

bonesy jonesy said:


> naimless said:
> 
> 
> > Mine is different
> ...


 

 They needed a bigger size to stuff all the new goodies in there.     HAHA    I don't know but it sure is a sweet sounding amp.    I had the new Violectric v281 for a while  and I have ZERO regrets switching to the Icon.


----------



## project86

I just measured my mkII (earlier version before the copper plate) and it is the same as naimless. So yes, the thing has grown a bit.


----------



## Rapid7

So I wasn't cracking up


----------



## dreambass

Paid for this today, brought it from audio affair with the upgraded Jensen caps and David Shaw valves and cant wait to fire it up.
 Not got a delivery date yet but i think early next week, will use it with the T-90's initially with the Fostex HP-A8 as dac


----------



## breizh

dreambass said:


> Paid for this today, brought it from audio affair with the upgraded Jensen caps and David Shaw valves and cant wait to fire it up.
> Not got a delivery date yet but i think early next week, will use it with the T-90's initially with the Fostex HP-A8 as dac


 
 Sure this combination will amaze you  !


----------



## dreambass

That's what i like to hear, i think so too and it arrives today so i am told. I have been impressed with the HP-A8  and also the T-90 but im not sure about the synergy between the two. I like the sound stage and the detail retrieval but it lacks a bit of something so will be interesting to see what it brings to the table.


----------



## shabta

I am thinking of getting this amp. Is the loop out a pass through so that I can connect to my stereo? Does the volume control affect the output through the loop our (can I use it as a pre to a power amp)?
  
 Thanks for the info!


----------



## naimless

As far as I know it's just a loop through,I don't think you can use the Hp8 as a pre amp unless you use the headphone socket on the front.


----------



## shabta

naimless said:


> As far as I know it's just a loop through,I don't think you can use the Hp8 as a pre amp unless you use the headphone socket on the front.


 
 Thanks! Does the unit have to be turned on?


----------



## naimless

shabta said:


> Thanks! Does the unit have to be turned on?




Sorry I don't know,I've never used the loop outs.


----------



## shabta

Well I pulled the trigger on a David Shaw upgraded version... Now the wait.


----------



## Xcalibur255

shabta said:


> Thanks! Does the unit have to be turned on?


 

 Looped outputs are passive, so no it would not have to be on.


----------



## shabta

What tubes have people found to be the best.
  
 Icon Audio advised me to get EH 6SN7 Gold Pin and JJ ECC83 gold pin. Supposedly the CV181s go microphonic very quickly. Any other suggestions?


----------



## Rapid7

shabta said:


> What tubes have people found to be the best.
> 
> Icon Audio advised me to get EH 6SN7 Gold Pin and JJ ECC83 gold pin. Supposedly the CV181s go microphonic very quickly. Any other suggestions?


 
  
 I purchased mine with the upgraded Jensen caps and it also came with the above tubes that Icon Audio advised. So far I am impressed and I'm more than happy with these tubes.


----------



## roskodan

i recently bought an early hp8 mk2 model, the one without the copper top plate, did anyone upgrade the pot with a stepped attenuator like the dact or khozmo, any improvements in sound?
  
 also what model/value exactly are the Jensen upgrade caps used by Icon Audio? any suggestion for some other ('better') caps i could upgrade too?
  
 EDIT: also i found some posts about the caps mod and comparison shots of the old and new ('copper plated') mk2 rev
  
 http://www.auriculares-hifi.com/foro/index.php?topic=1839.0


----------



## Hawkklein

I had V-Caps installed in mine. I'm currently using Full Music 6SN7 and one of the Telefunken red tipped select grade 12AX7. Sounds good to me. More than happy with it.


----------



## roskodan

Quote:


rapid7 said:


> shabta said:
> 
> 
> > What tubes have people found to be the best.
> ...


 
 EDITk i found shots online http://www.auriculares.org/foro/index.php?topic=6383.0
@Rapid7 (or anybody else for the matter) can you peek inside and read the Jansen caps' specs/model or take a shot?
  

  
 http://www.iconaudio.com/jensen-capacitors/
  
 http://www.iconaudio.com/products-page/copper-foil/copper-foil-0-33%C2%B5f-630-volts/

  


hawkklein said:


> I had V-Caps installed in mine. I'm currently using Full Music 6SN7 and one of the Telefunken red tipped select grade 12AX7. Sounds good to me. More than happy with it.


 

 FM 6SN7 red labeled with gold base and pins? or the gold labeled? is there any difference between the two?


----------



## Hawkklein

The FM6SN7 I'm using are gold labeled. There may be differences between the two but, if so, I'm unaware of what they might be.


----------



## roskodan

asking cos i saw icon audio having the red label ones for sale, while most of em from chinese sellers on ebay are the gold label, guess it's just different batches
  
 btw, for those looking to get this amp, from the deals threads hd800 + hp8 mk2: http://www.avclass.com/offers//atsoluciones-packs-icon-audio-hp8-mkii-sennheiser-hd800.html
  
 1499EUR including shipping within the EU, and other countries get the VAT reduction... pretty sweet! order by email to get free shipping!


----------



## shabta

roskodan said:


> asking cos i saw icon audio having the red label ones for sale, while most of em from chinese sellers on ebay are the gold label, guess it's just different batches
> 
> btw, for those looking to get this amp, from the deals threads hd800 + hp8 mk2: http://www.avclass.com/offers//atsoluciones-packs-icon-audio-hp8-mkii-sennheiser-hd800.html
> 
> 1499EUR including shipping within the EU, and other countries get the VAT reduction... pretty sweet! order by email to get free shipping!


 
 The Icon and the HD800 are a fantastic pair. It is hard to get the HD800s off my head...


----------



## roskodan

@shabta what tubes have you been using with the hp8 mk2, any particular preference with the hd800? do you have the older revision or the new with the copper top plate?
  
 i got these beside the stock ones that came with my older model
  
 http://www.ebay.com/itm/300674397595
  
 http://www.ebay.com/itm/290607196555
  
 also been looking at these:
  
 http://www.ebay.com/itm/250957662524
  
 http://www.ebay.com/itm/400503930912
  
 http://www.ebay.com/itm/250919409764
  
 any nos recommendation?


----------



## shabta

roskodan said:


> @shabta what tubes have you been using with the hp8 mk2, any particular preference with the hd800? do you have the older revision or the new with the copper top plate?
> 
> i got these beside the stock ones that came with my older model
> 
> ...


 
  
 I have the newer copper top model. I am using EH SN67 Gold Pins and JJ 12
  
  


roskodan said:


> @shabta what tubes have you been using with the hp8 mk2, any particular preference with the hd800? do you have the older revision or the new with the copper top plate?
> 
> i got these beside the stock ones that came with my older model
> 
> ...


 
 I have the newer copper top model. Based on the suggestion of Icon Audio I am using EH 6SN7 Gold Pin and JJ ECC83. I am quite happy with them. They are more airy and smoother on top then the stock tubes.


----------



## roskodan

good, same as the ones i ordered, tho my stock tubes are different from the newer copper top plate revision


----------



## shabta

roskodan said:


> good, same as the ones i ordered, tho my stock tubes are different from the newer copper top plate revision


 
 Look forward to hearing your impressions after you get the new tubes...


----------



## roskodan

i'm using it with a hd800, will be a couple more days before i get em tubes... customs doh... i'll have a v200 to compare too... right now with stock chinese 12ax7b and ElectronTube 6sn7gt, it's really clean and tight on low gain, quite balanced, lot of gain maybe a tad much, luckily i've a chord hugo so i can lower the source output
  
 EDIT: ok, with hd800, the amp, stock tubes, is unlistenable with a standard output source ~2V, no headroom, congested bass, lowered the hugo's output to the hp8's nominal 300mV, much much better, tho i can still hear potential in tube, caps and pot upgrades...
  
 EDIT2: now i ordered the jensen caps too... T-T


----------



## roskodan

anyone upgraded the pot? perhaps to a stepped one like a dact type pot?


----------



## roskodan

the electro harmonix gold 6sn7 and JJ gold 12ax7 ecc83 came in today, wow, didn't expect such a positive change in sound, details just popped out without losing naturalness, and the response is more balanced, stronger, faster... great job from the russians and slovaks
  
 now i'm really tempted to go for the export shuguang treasures and psvane t-series... yaaaa taaaa


----------



## shabta

roskodan said:


> the electro harmonix gold 6sn7 and JJ gold 12ax7 ecc83 came in today, wow, didn't expect such a positive change in sound, details just popped out without losing naturalness, and the response is more balanced, stronger, faster... great job from the russians and slovaks
> 
> now i'm really tempted to go for the export shuguang treasures and psvane t-series... yaaaa taaaa


 
 Ya the tube upgrade isn't subtle. The problem with the shuguang and pavane according to Icon is that they die fast. Sometimes in as little as six months. They said they sound only a slight bit better, which for the money and longevity issue makes them  a no go for me.


----------



## roskodan

ah you just reminded me about those issues, there are some suspicious and cheap, 130USD, treasures cv181-z matched pairs on ebay, with 1 year warranty, while the premium export boxed pairs from factory direct US/UK sellers are 250USD and only 90 days of warranty, same story for the t-series mk2 psvane 12ax7, don't know if i'll be able to resist tho
  
 the jensen caps are coming, maybe they will fix the itching


----------



## shabta

Does anything ever totally fix the itch?


----------



## fzman

preparation-H?


----------



## roskodan

nah... i'm more into natural remedies, the jensen should do just fine (as suppository)


----------



## dreambass

I have the factory upgrades and music is far nicer to listen to in most areas compared to the fostex hp-a8 internal amp although maybe the speed/precision of the fostex is superior although the soundstage, micro details and fulleness to the sound not forgetting the authority are a big advantage to the icon as are female vocals. Really a no contest after a listening session. I use the fostex as dac for the icon.
So has Anybody listened to the fostex th-900 on the icon, im interested as i liked the 900s and my shure 1540s sound great on it, bass a bit more prominent though compared to the T-90s, a decent match with the beyers


----------



## roskodan

i don't know what headphones do you use with the hp8 but in my experience efficient, low impedance, headphones suffers from too much noise, perhaps my AC is very noisy, ymmv


----------



## dreambass

I have been using the shure 1540s and also the T-90s and have no issue with noise with regards to impedance its good in that respect on the akg 550 and sony mdr1also.


----------



## roskodan

i've the mdr-1r, surprisingly good with tubes, one of the best cans with the wa6, but even on low gain i can feel some 50/60Hz hum when i plug and unplug em, and on high gain it can be heard pretty loud when not playing any music, i guess my ac is quite dirty


----------



## roskodan

i was all set to upgrade the caps this weekend, when i realized i had no more solder, hopefully will find some to borrow...
  
 they changed the print design on the Jensen caps, at first i thought these were counterfeits, turned out not... checked out with jensen and those are the new print design from 2014


----------



## roskodan

job done (tho i reversed the caps, fixed that later http://www.head-fi.org/t/492604/icon-audio-hp8-mp-3/315#post_11828430)


----------



## roskodan

spakka said:


> So, I have a quick question now I have the capacitors (delivered rather quickly!)...
> 
> I have the Jensen ones and they suggest placing them so that the outer foil is closest to the grounded side of the circuit (the output stage?) and the inner foil is closest to the positive side - I think this means the inner foil (which is marked by the black line on the cap) should be connected to the 6SN7, and the unmarked outer side to the 12AX7.
> 
> ...


 

 schiit i reversed em, oh well i'll switch em tomorrow, will be fun to see if i can hear the difference XD
  
 btw detail and tone correctness improved a lot over the stock caps, listening to blue oyster cult and judas priest, those guitars now sound much more defined, detailed in tone, everything improved, can't wait to turn em around and be re-amazed!!!


----------



## roskodan

voilà, better than ever... now the fun part... listening session!


----------



## roskodan

dreambass said:


> I have been using the shure 1540s and also the T-90s and have no issue with noise with regards to impedance its good in that respect on the akg 550 and sony mdr1also.


 

 thx for your input, i got suspicious of the noise i was getting with my mdr-1r and checked for grounding issues and found i had a ground breaking and loop, got rid of that now it's super quiet in comparison!


----------



## dreambass

Fair play ear's don't lie i guess.
The shure 530s are not nice on the icon though tried them a few days ago.


----------



## roskodan

i've em se530 too, these hiss from any device i tried em with, the hugo is ok, the v200 is maybe a tad warm, i didn't even try with the hp8, not planing either, haha, from memory the wa6(se) was quite more fit with very low impedance cans (<50ohm), it has 15 ohm output impedance vs the hp8's 32 ohm (at L output)
  
 also i was stacking the hp8 on my v200's top,* and guess what?*
  
 depending which side of the hp8 was closer to v200's transformer side, it made the hp8's L or R channel hum quite a bit with the mdr-1r, now i need to move em apart a little, *20cm more apart *resolves the hum completely, so no big issue


----------



## dreambass

I don't use the 530s anyhow but agree on hiss issues.Only the 1540s and T-90 really. The others are redundant in my collection think i need to shift them but not worth alot.
Might upgrade cans soon any favourites on the Icon particularly?


----------



## Lavakugel

I want to buy my first tube amp. Considering HP8 or Woo WA6. Which one is the better choice?


----------



## roskodan

lavakugel said:


> I want to buy my first tube amp. Considering HP8 or Woo WA6. Which one is the better choice?


 
  
 what type of sound are you looking for? what cans?


----------



## Bartez75

roskodan said:


> thx for your input, i got suspicious of the noise i was getting with my mdr-1r and checked for grounding issues and found i had a ground breaking and loop, got rid of that now it's super quiet in comparison!


 

 Hi
 I have this amp as well and can hear some noise. Can you explain what you mean that you had ground breaking and loop? How did you solve it? I will appreciate your input.
 Thanks in advance.


----------



## roskodan

*do NOT open the amp, there are very dangerous voltages inside even after you turn it off and unplug the power cord**!!!*
  
 is it present in one channel more than the other or both equally?
  
 is it low bass hum, or higher hiss? or both? (the low hum is usually in the center, both channels equally, the hiss may be more present in one channel)


----------



## Bartez75

It is a low hum in both channels.


----------



## Lavakugel

roskodan said:


> what type of sound are you looking for? what cans?


 

 Already have a ss amp so I'm looking for a romantic tubey sound with hd600


----------



## roskodan

lavakugel said:


> roskodan said:
> 
> 
> > what type of sound are you looking for? what cans?
> ...


 
 wa6 is more euphonicaly tubey but lighter in sound, the hp8 is more full sounding compared to the wa6, both articulates and separates excellently, i would give an edge to the hp8 in power and authority but the wa6 is more vivid sparkling, romantic, more airy
  
 both respond well to tube rolling, on the wa6 you can roll the rectifier too, while the hp8 has a dual (6sn7) mono tube power stage and a nice gain 12ax7 tube
  
 on both is important to get nice tubes
  
 there is a nice deal on hp8 + hd800 http://www.head-fi.org/t/492604/icon-audio-hp8-mp-3/300#post_11763257


----------



## roskodan

bartez75 said:


> It is a low hum in both channels.


 

 is it bad/loud at L output with hd800?
  
 it sounds like you have a noisy AC or ground loop, or the amp to close to other amps or devices with power supplies,
  
 try it in a different room, or with other devices unplugged from the wall (pc, laptop adapter, fridge etc...)
  
 EDIT: also try with no input cables from the source (dac, cd player etc...)


----------



## Lavakugel

roskodan said:


> wa6 is more euphonicaly tubey but lighter in sound, the hp8 is more full sounding compared to the wa6, both articulates and separates excellently, i would give an edge to the hp8 in power and authority but the wa6 is more vivid sparkling, romantic, more airy
> 
> both respond well to tube rolling, on the wa6 you can roll the rectifier too, while the hp8 has a dual (6sn7) mono tube power stage and a nice gain 12ax7 tube
> 
> ...


 

 That deal is really excellent! But romantic, airy and vivid speak for wa6 and you can change all tubes and reftifier and that will bring a huge improvement...


----------



## roskodan

lavakugel said:


> That deal is really excellent! But romantic, airy and vivid speak for wa6 and you can change all tubes and reftifier and that will bring a huge improvement...


 
 yeah, i guess you can find one in the classifieds and save some more, usually bundled with extra tubes


----------



## Lavakugel

How is that deal even possible...1400 eur for both hd800 and hp8. In my country hd800 is 1200 eur. Really interested in getting hd800...


----------



## dreambass

Agreed but you can obviously watch capacitance discharge using an ohm meter  Recomended ha.


----------



## Xcalibur255

Most competently designed tube amplifiers have bleeder resistors across the storage capacitors.  They are normally discharged in less than 30 minutes after removing power from the unit.  I wouldn't make any assumptions about the presence of high voltage inside the unit unless you know for a fact that those resistors are there though.  There is usually enough capacitance there to stop your heart at the 250 volts you'll find inside.


----------



## dreambass

xcalibur255 said:


> Most competently designed tube amplifiers have bleeder resistors across the storage capacitors.  They are normally discharged in less than 30 minutes after removing power from the unit.  I wouldn't make any assumptions about the presence of high voltage inside the unit unless you know for a fact that those resistors are there though.  There is usually enough capacitance there to stop your heart at the 250 volts you'll find inside.



I would asume there is voltage there until i had checked but correct.


----------



## roskodan

lavakugel said:


> How is that deal even possible...1400 eur for both hd800 and hp8. In my country hd800 is 1200 eur. Really interested in getting hd800...


 

 i bought from em, contact by email and ask for a paypal invoice and you will get 1499 free shipping, hd800 goes for 850-900 eur shipped and the hp8 goes for 750-800 eur shipped


----------



## roskodan

dreambass said:


> xcalibur255 said:
> 
> 
> > Most competently designed tube amplifiers have bleeder resistors across the storage capacitors.  They are normally discharged in less than 30 minutes after removing power from the unit.  I wouldn't make any assumptions about the presence of high voltage inside the unit unless you know for a fact that those resistors are there though.  There is usually enough capacitance there to stop your heart at the 250 volts you'll find inside.
> ...


 

 you can turn off the amp while you are still listening and it will play for another 20-30 seconds, as the sound drops rise the volume and gain until there is no more sound coming from the amp, that way it will be safer after 30min


----------



## dreambass

I noticed that a nice lil fade out when your done listening eh. I wasn't expecting that though.
Only got interested in valves after years of my dad banging on about guitar amps. Glad i did though


----------



## roskodan

btw, this mdr-1r i got is really nice out of tube amps, with the wa6 before and now with the hp8, gives piano and orchestra some really pleasing bloom, euphony, it prat very well 
  
 i need to try more low ohm dynamic hp with tubes
  
 EDIT: this one album really gets me emotional (i like a lot the studio ghibli and takeshi kitano movies), joe hisaishi is really great at it
  
 https://www.youtube.com/watch?v=38ELUdT_8cQ&list=PL8DFCC0D739A55A99


----------



## dreambass

Best i ever hear........ever, sony all the way


----------



## Thenewguy007

Anyone compared these to the Bottlehead Crack with Speedball upgrade?
  
 Both of these amps are on InnerFidelity's "Wall of Fame".
  
 Tyll doesn't differentiate between the two in his reviews.
  
 Is the Icon a upgrade or sidegrade to the BH Crack Speedball?


----------



## project86

thenewguy007 said:


> Anyone compared these to the Bottlehead Crack with Speedball upgrade?
> 
> Both of these amps are on InnerFidelity's "Wall of Fame".
> 
> ...


 
  
  
 That's because I awarded the Icon while Tyll awarded the Crack. I don't think he has ever heard the Icon, and while I used to have a Crack/speedball, it wasn't concurrent with the HP8, so no direct comparisons.
  
 I will say Crack/speedball is probably the better bang for your buck, especially if you mainly use HD650 or other high-impedance cans. If you may venture into lower impedance models or especially planar headphones, the Icon is drastically better imho.


----------



## dreambass

I think my icon may have a crystallised soldered joint as a few nights ago I could hear muffled cb radio through it, very strange, I initially thought the volume was low then realised I did not have the source playing. I did not hear it again last night when I tested it. 
Any ideas on this apart from sending it back, or opening it whilst still in warranty period


----------



## shabta

project86 said:


> That's because I awarded the Icon while Tyll awarded the Crack. I don't think he has ever heard the Icon, and while I used to have a Crack/speedball, it wasn't concurrent with the HP8, so no direct comparisons.
> 
> I will say Crack/speedball is probably the better bang for your buck, especially if you mainly use HD650 or other high-impedance cans. If you may venture into lower impedance models or especially planar headphones, the Icon is drastically better imho.


 
 I can't measure based on bang for buck. But I liked the presentation of the Icon with the HD800 a little better than the crack, didn't hear a speedball though. I especially like the fullness of the bass with icon and the smooth highs. It has a classic SET sound.  I have the newer one with upgraded tubes (2 EH goldpin and JJ gold) and like to turn the selector knob to the highest impedance setting. It seems the Icon is cheaper in europe (or it was when I bought it at about 750 USD) than in the US. So maybe depends where you live when assessing the cost benefit ratio.


----------



## dreambass

roskodan said:


> btw, this mdr-1r i got is really nice out of tube amps, with the wa6 before and now with the hp8, gives piano and orchestra some really pleasing bloom, euphony, it prat very well
> 
> i need to try more low ohm dynamic hp with tubes
> 
> ...


The srh 1540 really does sound great to my ear's from icon. 
Think I need to test those He1000's though burning urge to spend cash ha.


----------



## cheznous

Really like these PSVANE matched tubes in my HP8. 
Not cheap though.


----------



## roskodan

wow... and ouch ! i got the shuguang treasures cv-181z and the fullmusic 6sn7 with the psvane 12ax7 treasure mk2 which is kind of complementary to the jj tesla 12ax7 gold pin, the cv-181z are the fuller smoothest without veil, while the fullmusic are really crisp and invitingly hot vivid sounding without harshness (hp8 with jensen caps and hd800), now i need to try some nos


----------



## cheznous

roskodan said:


> wow... and ouch ! i got the shuguang treasures cv-181z and the fullmusic 6sn7 with the psvane 12ax7 treasure mk2 which is kind of complementary to the jj tesla 12ax7 gold pin, the cv-181z are the fuller smoothest without veil, while the fullmusic are really crisp and invitingly hot vivid sounding without harshness (hp8 with jensen caps and hd800), now i need to try some nos




I really like the Philips Jan 12ax7. Seems to compliment the PSVANE 's. 
As an aside the light on mine is red, apparently blue too bright for some folks and other experiments didn't really work.


----------



## Solitary1

Just installed some TJ Full Music 6SN7's with Genalex Gold Lion 12AX7. Must say, even with no burn-in the Full Music's sound better that my Sylania's 6SN7GTB chrome dome and my Psvane 6SN7's (to my ears). I still have to do the cap upupgrades.


----------



## BearMonster

Just gotten my Icon Audio Hp 8 MKII. Must say it was a lot bigger then what i thought. 
I've gotten myself the EH 6sn7 gold pin and JJ 12ax7, wished i gotten the David Shaw cv 181. I also have gotten the copper plate model and have a red led light led instead of blue or purple. On the manual for those with copper plate state "The Latest version of the HP8 copper plate has a "loop" through facility which enables the permanent connection in a hi-fi system". so i guess it not just a different look.

Does anyone know what this GND on the back does i don't see anything on the manual about that. and what is better mono or stereo for listening.


----------



## roskodan

@BearMonster
  
 well eh6sn7 + gold pin jj 12ax7 i really dig this combo, i ve fullmusic and shuguang treasures 6sn7 too as well as the psvane treasure mk2 12ax7, those do change the signature somewhat but sq wise the eh+jj is just as good, i m using a hd800 on high z out, gain, mostly,
  
 i ve the older version hp8, the mono is for mono recordings, the loop is so u can forward the source signal from the hp8 to other hi-fi equipment,
  
 also the caps upgrade is rly a must imo


----------



## svmusa

Curious if this amp can drive both low and high impedance cans? The highest I have is 250 Ohms Beyer and lowest is 16 Ohms. Thx


----------



## breizh

svmusa said:


> Curious if this amp can drive both low and high impedance cans? The highest I have is 250 Ohms Beyer and lowest is 16 Ohms. Thx


 

 So you can compare !
 The synergy is great with the Beyer T1 which is 600 ohms - it's a very powerful amp too, no need to go more than 10 with the Beyer
 And great with low impedance cans also, such as AKG K550 and DT880


----------



## shabta

It definitely drives my high impedance HD800s beautifully. And my low impedance NAD HP50s sound good too ( but this amp is waaay overkill for these phones). Haven't tried any iems...
  
 On another note I just switched in some NOS sylvania 6n75s from the 70s, really nice and not expensive. Running the gold pin jj 12ax7, liked it better than some 70s telefunken tube I had...


----------



## roskodan

yeah runs excellent with both high and low impedance fullsize headphones, thats why there is the impedance selection knob, i run my hd800 on high setting, but being a transformer coupled output you can run even low impedance cans on the high output as i usually do cos it is a nice change in sound, definitely noticeable, actually pretty drastic, hd800 on low output are as good, depending on ones mood, tho very efficient cans will pick up more noise, so for those, one really wants to have a clean AC, also the caps upgrade to the jensen copper foil in oil with silver leadouts (or better, if you ve any favorites) is mandatory imo, resolution and overall transient, soundstage precision and what not, just skyrocket to another level, i did the comparison with the stock ones, i was skeptical at first tho after listening i simply realized how wrong i was XD
  
 with stock tubes and caps, it's really a woolly sounding amp, some fullmusic 6sn7 and the jj tesla 12ax7 gold will make it a true tube amp, more like the wooz (woo audio), tho if u fit the shuguang treasures 6sn7 and a psvane treasure 12ax7 mk2 u gonna get that warm breeze, yet still (maybe even more) dynamic
  
 absolutely great amp, especially in a deal like this one ^^ http://www.atsoluciones.com/atsoluciones-packs-icon-audio-hp8-mkii-sennheiser-hd800-es.html
  
 but i ve an even better deal if u want only the amp (EU sale) http://www.head-fi.org/t/789281/icon-audio-hp8-mk2-maxed-special-edition-optional-tubes


----------



## nubje

Just ordered this with the upgraded valves, cant wait 
	

	
	
		
		

		
			




  
 Looking to pick up a 2nd hand T1 or HD800 now
  
 What kind of DACs do you guys run with it? I need something with USB in and RCA out that isn't too expensive


----------



## roskodan

the hp8 is not really picky about the dac but it will scale with a better dac, so i suggest u get a 500USD+ dac (that has good feedback here in the forums), and ofc a HD800, the new one hd800s is soon to be released i think, so perhaps there will be some deals in the classifieds for used old ones


----------



## shabta

@roskodan why are you selling your amp? BTW I haven't heard all the woo amps, but the ones I heard sounded too warm and gooey to me. I like the much more neutral nature of the Icon.


----------



## roskodan

if u check my trade feedback u ll notice i'm always changing my setup at least 2-3 times a year, this is how i roll, and i like to give awesome deals to headfiers


----------



## project86

nubje said:


> Just ordered this with the upgraded valves, cant wait
> 
> 
> 
> ...


 
  
 I enjoy the HP8 from simple little DACs like the Resonessence Labs Concero or the Audinst DX1, as well as my bigger/more expensive reference DACs. HP8 is transparent enough to show the improvement but not ruthless enough where the more affordable stuff sounds terrible.
  
 Check out the Concero and DX1 though, both quite nice. DX1 is new so not a lot of feedback out there yet... it's pretty impressive. Or find a used Concero for a low price on the forums.
  


shabta said:


> @roskodan why are you selling your amp? BTW I haven't heard all the woo amps, but the ones I heard sounded too warm and gooey to me. I like the much more neutral nature of the Icon.


 
  
  
 I have respect for Woo but agree, they certainly have a more colored sound. Plus the higher models don't necessarily get better as you go.... personally I like the standard WA6 for the price, as compared to the SE which isn't a great design and costs too much for what it is.


----------



## LFC_SL

roskodan said:


> if u check my trade feedback u ll notice i'm always changing my setup at least 2-3 times a year, this is how i roll, and i like to give awesome deals to headfiers



What are you changing to?


----------



## roskodan

hm, idk, let's say i'm rediscovering my love for musicality  k701 + v200 with the hrt music streamer hd, but i'm still using the hp8 more, cos with the cv-181z and the psvane 12ax7 Tmk2 it's just too good to let go,
  
 so yeah, it's something i could not decide, so i put both amps for sale and waiting to see which one goes first, with the hp8 one can tune the sound by a substantial range for all dynamic driver cans, from my mdr-1r, akgk701, hd800, even the most difficult low Z planars to drive, the MrSpkrs AD (lets just forget about the He-6) are well driven by it,
  
 tho i find it to be better suited for dynamic driver hp cos it complements them for what they lack vs planars, basically u don't need planars with this amp, unless u really want the smoothest sound possible XD, and that full size body presence ofc, perhaps some more balanced planars like the new ether or he560 would be a perfect match for it! idk XD everything is possible,
  
 but yeah the tubes will affect a lot the sound in my experience, i use only current production tubes, cos NOS don't perform consistently, an old tube is an old tube, even if it was never used, especially with hard to drive cans u need healthy tubes


----------



## svmusa

roskodan said:


> yeah runs excellent with both high and low impedance fullsize headphones, thats why there is the impedance selection knob, i run my hd800 on high setting, but being a transformer coupled output you can run even low impedance cans on the high output as i usually do cos it is a nice change in sound, definitely noticeable, actually pretty drastic, hd800 on low output are as good, depending on ones mood, tho very efficient cans will pick up more noise, so for those, one really wants to have a clean AC, also the caps upgrade to the jensen copper foil in oil with silver leadouts (or better, if you ve any favorites) is mandatory imo, resolution and overall transient, soundstage precision and what not, just skyrocket to another level, i did the comparison with the stock ones, i was skeptical at first tho after listening i simply realized how wrong i was XD
> 
> with stock tubes and caps, it's really a woolly sounding amp, some fullmusic 6sn7 and the jj tesla 12ax7 gold will make it a true tube amp, more like the wooz (woo audio), tho if u fit the shuguang treasures 6sn7 and a psvane treasure 12ax7 mk2 u gonna get that warm breeze, yet still (maybe even more) dynamic
> 
> ...


 
 Thx, I was planning to drive Fostex TH900 out of these with some NOS tubes, but kind of skeptical with 24 ohms impedance and high sensitivity I might pick noise.


----------



## nubje

So I received my HP8 yesterday, I ordered the upgraded version from audioaffair.co.uk
  
 The upgraded version "_incorporates a Jensen capacitor upgrade, an upgrade from the standard 6SN7 valves to David Shaw CV181 and a gold pin 12AX7 rather than the standard 12AX7 valves"_
  
 I noticed that the valves that came shipped with the HP8 are Electro Harmonix gold pin 6SN7 rather than the David Shaw CV181
  
 I rang Audio Affair today and after sending them some photos they replied via email
  
_This is the upgraded valve, at one point they were fitting the CV181 DS, however due to harmonic distortion after periods of use it was decided to stick with 6SN7, they do a cheaper Shuguang and the Harmonix is the upgraded version like you have. You can of of course have the CV181DS - not a problem we can get these swapped out for you however Icon no longer recommend this. _
  
Any one experienced this harmonic distortion or can shed any light on this?


----------



## naimless

I don't think so but on the other hand I'm not exactly sure what harmonic distortion sounds like.


----------



## shabta

nubje said:


> So I received my HP8 yesterday, I ordered the upgraded version from audioaffair.co.uk
> 
> The upgraded version "_incorporates a Jensen capacitor upgrade, an upgrade from the standard 6SN7 valves to David Shaw CV181 and a gold pin 12AX7 rather than the standard 12AX7 valves"_
> 
> ...


 
  
 The CV181's seem to go microphonic very quickly in the Icon amp. Sometimes as quickly as six months. That's according to a sales rep I communicated with at Icon when I was thinking of upgrading tubes. YMMV of course.


----------



## roskodan

no problem here with my new (post anniversary) cv181z treasures,
  

  
 guess it was something with the old stock discontinued anniversary edition for which sellers are milking absurd amounts, especially the ones sold in some fancy presentation boxes with all kind of 'documents', major bs,


----------



## shabta

roskodan said:


> no problem here with my new (post anniversary) cv181z treasures,
> 
> 
> 
> guess it was something with the old stock discontinued anniversary edition for which sellers are milking absurd amounts, especially the ones sold in some fancy presentation boxes with all kind of 'documents', major bs,


 
 Well that isn't what the Icon Audio rep told me. They cautioned against getting the tubes you have as well. He didn't say that they would go microphonic after six months, he said they may and in any case they will go microphonic much more quickly than is reasonable. Especially compared to the 6ns7... So one contrary data point doesn't disprove the general statement.


----------



## roskodan

mr fox never tasted those ripe grapes cos they were visibly sour


----------



## nubje

Hm, another issue now
  
 I'm getting a background hum/static noise when this amp is connected directly to my PC. Its pretty quiet but annoyingly noticeable. I get it also when the amp is connected to a Cambridge Audio XS USB dac/amp which is plugged into the PC or directly into my PCs line out.
  
 Hum doesn't appear when I connect the amp to my laptop (either directly or via the Cambridge Audio XS) or to my phone.
  
 When I connect my headphones to my PCs lineout or to the Cambridge Audio theres no background hum, its completely silent.
  
 I realise this isn't the amps fault, any ideas though? 
  
 I've tried connecting the amp to a different power socket 2meters away from the PC, no difference.


----------



## project86

Sounds like a ground loop issue, unfortunately the amp is sensitive to them. They can be a bear to solve but google it and see. I've had good luck using certain power conditioners or strips, sometimes even a basic device can help (it doesn't have to be some multi-thousand dollar thingy).


----------



## nubje

I got an ODAC delivered today which has made a difference. The hum is still there but only when volume is set very high, on normal listening volumes I need to really listen hard to notice anything over background noise.
  
 Will this be exacerbated going from current headphones (62 Ohm) to T1s (600 Ohm) ?


----------



## project86

Higher impedance may actually minimize it. Really depends on the sensitivity more than impedance though.


----------



## nubje

Managed to fix it with a HifimeDIY USB Isolator
  
 God damn this is a good amp


----------



## shabta

nubje said:


> Managed to fix it with a HifimeDIY USB Isolator
> 
> God damn this is a good amp


 
 Good tip! and yes it is a really good amp.


----------



## shabta

Yesterday i just finished a review of the new HD800 S and compared it to the HD800. The Icon HP8 is an important supporting character. I thought some of the HP8 fans might enjoy the read...
  
 http://www.head-fi.org/products/sennheiser-hd-800-s/reviews/14950


----------



## BearMonster

Looks like i've developed a problem, I've got this hum which is different compared to the background hum i would normally hear.
  
 This hum is not connected to the volume as i have turn this all the way & right back & has remained the same never getting louder or quieter. Also i've disconnected everything & only plug this into the socket & still get this hum.
  
 So can someone help me?


----------



## shabta

I have found that the folks at Icon audio are super responsive. Have you tried also asking them?


----------



## BearMonster

Yep contacted Icon audio probably get back to me on monday.


----------



## project86

Could be a ground loop, those show up even without RCA connections sometimes. Or could be transformer hum which is an unfortunate necessity at times.... I've gone through quite a few balanced power conditioners from BPT and Equitech and many/most of them have transformer hum. It's just a matter of finding one which is less obvious. Hopefully Icon can help.


----------



## nubje

I've found this amp is super sensitive to interference. I was getting an intermittent buzzing noise which I just couldn't fix, I ended up moving my phone away from my desk and the noise disappeared.
  
 I have my phone close again now and its not making the same noise. Honestly have no idea what it was
  
 As an aside, I'm listening to this with the beyerdynamic T1s, absolutely lovely.


----------



## dreambass

I have heard what sounds like cb radio through mine, i was surprised that i had found something new on the disc. However surprise led to a haunting feeling after i listened for this again. Must have been six months ago and i have had no issues with the unit recently.


----------



## BearMonster

[Deleted]


----------



## stuart1927

I just got the Icon HP8 Mk II via analogue seduction in the UK. Pretty good price v's the retailers here in the US. It has the David Shaw CV181 tubes and standard caps etc. I thought I'd share my initial impressions.
  
 Initially, I was not crazy about the sound as it seemed  detached / distant somehow. I thought this might be due to the base Chinese 12AX7 tube, but I let things burn in for an entire weekend and wow....what a transformation! I've never heard such a massive change due to burn in! I have a lot of other gear, tube and solid state, but have never heard such a change after burn in (only 72 hrs or so). I wonder if anyone else has noticed this?
  
 Anyway, I have ordered some Sylvania Black Plate 6SNWGTA tubes and a gold lion 12ax7 ....will be interesting to see how they sound v's the stock tubes, which are sounding pretty good in their own right. 
  
 I did a comparison with my ifi micro dsd and really there was no comparison in my view. I use the ifi micro dsd with the ibasso DX80 as my travelling rig, which it is great for. However, by comparison, the Icon sounds extremely natural, with much wider sound-stage and great separation. A very neutral sound for tubes, with controlled bass, certainly not in your face. I suspect this amp is perfect for classical music. I suspect tweaking of tubes will bring some extra warmth and bass for those who need it.
  
 I'm using Alpha Prime headphones.....really nice pairing too!
  
 When I get some time, I will compare with my Cavali liquid carbon, which I got recently and also really enjoy.


>


----------



## project86

Nice, thanks for the impressions. I agree, it sounds great with Alphas and other planars. I've had more than my fair share of tube amps which sounded stunning with something like an HD650, but couldn't drive a planar headphone with satisfactory results.


----------



## stuart1927

Picked up the Musical Paradise MP-D1 tube dac to match up with the HP8, What a combination! Having a lot of fun with this combo...superb!


----------



## ummon

I'm also interested in DAC recommendations for pairing with Icon and HD800.
 Why did you end up deciding on MP-D1?


----------



## stuart1927

ummon said:


> I'm also interested in DAC recommendations for pairing with Icon and HD800.
> Why did you end up deciding on MP-D1?


 
 I spent a lot of time researching various options and pulled the trigger on the MP-D1 mainly due to other positive reviews and also the build quality. I upgraded to the Jensen caps and also upgraded the tubes. The combination is superb and (IMHO) is superior to the Cavali Liquid carbon paired with the emotiva stealth DC-1, which is one of my other rigs. This is by no means a bad combo, it's just bettered by the Icon/ MP.
  
 I see Musical Paradise have now released their MP-D2 dac, which is quite a bit more expensive, but looks like an end game dac. I have a DNA Stratus on order currently and think the MP-D2  might be a great option for that amp.
  
 With the Icon and MP-D1 I don't think you'll be disappointed, it's great with classical, jazz, rock and everything else I've listened to. I have the Alpha Prime headphones btw. I think the HD800's would suit the MP-D1 and Icon very well. The sound is detailed, but on the warmer side of neutral, so might tame the HD800's a tad. 
  
 Stuart


----------



## ummon

Well, I ordered Mullard long plates for preamp and a pair od VT-231 Sylvania tubes, so I hope that would tame HD800, along with some copper cable upgrade.
 Review I found on innerfidelity for DP-1 was not very favorable so I need to test it in my rig before deciding. If I go for MP-D2 then I would probably want to upgrade to a balanced amp.


----------



## stuart1927

ummon said:


> Well, I ordered Mullard long plates for preamp and a pair od VT-231 Sylvania tubes, so I hope that would tame HD800, along with some copper cable upgrade.
> Review I found on innerfidelity for DP-1 was not very favorable so I need to test it in my rig before deciding. If I go for MP-D2 then I would probably want to upgrade to a balanced amp.


 
 Review on innerfidelity for MP-1 not very favorable? Sounds like exactly the kind of characteristics you'd be looking for with the HD-800?
  
*Sound Quality: MP-D1 DAC*
 Here again, in a word---SMOOTH. There is plenty of detail, although for sure the MP-D1 is not the last word in detail. Very good detail for its price class, yes, but it does not set any benchmarks here. That said, in terms of musicality, it is one of the best I have heard in the under $1K price range. The sound was utterly unfatiguing, spacious, relaxed, and engaging. The presentation is definitely on the lush/romantic side of things, but not so far to seem like a coloration. It's less "tubey", in absolute terms, than the MP-301 is. There is no issue at all with extension at either frequency extreme. Bass response is very good, and has nice weight to it. Again, it's not the very last word in bass definition, but the bass doesn't seem sloppy or loose in any way without direct comparison to something like my much more extensive Red Wine Audio Isabellina Pro. The mids were natural and organic. I have heard greater overall transparency, but the MP-D1 doesn't come off as thick or veiled, either. At the risk of sounding trite or repeating myself, it comes across as musical in the best use of the term. I simply enjoyed listening to music through it.
 Read more at http://www.innerfidelity.com/content/musical-paradise-mp-301-mk-3-vacuum-tube-integratedheadphone-amplifier-and-mp-d1-vacuum-tub-0#QOutoxR1LXPOKhWB.99


----------



## project86

Yes, I did not take that as a negative review either, just a specific sound which may or may not be a good match based on a number of factors.


----------



## ummon

Hmm, yes what I always searching is an extreme value for a price, but that depends on synergistic effects with the rest of my components.
 I will wait until my upgrades come, and then I will see if I need a musical or more neutral/transparent DAC for HD800.
   
 Quote:


stuart1927 said:


> Review on innerfidelity for MP-1 not very favorable? Sounds like exactly the kind of characteristics you'd be looking for with the HD-800?
> 
> *Sound Quality: MP-D1 DAC*
> Here again, in a word---SMOOTH. There is plenty of detail, although for sure the MP-D1 is not the last word in detail. Very good detail for its price class, yes, but it does not set any benchmarks here. That said, in terms of musicality, it is one of the best I have heard in the under $1K price range. The sound was utterly unfatiguing, spacious, relaxed, and engaging. The presentation is definitely on the lush/romantic side of things, but not so far to seem like a coloration. It's less "tubey", in absolute terms, than the MP-301 is. There is no issue at all with extension at either frequency extreme. Bass response is very good, and has nice weight to it. Again, it's not the very last word in bass definition, but the bass doesn't seem sloppy or loose in any way without direct comparison to something like my much more extensive Red Wine Audio Isabellina Pro. The mids were natural and organic. I have heard greater overall transparency, but the MP-D1 doesn't come off as thick or veiled, either. At the risk of sounding trite or repeating myself, it comes across as musical in the best use of the term. I simply enjoyed listening to music through it.
> Read more at http://www.innerfidelity.com/content/musical-paradise-mp-301-mk-3-vacuum-tube-integratedheadphone-amplifier-and-mp-d1-vacuum-tub-0#QOutoxR1LXPOKhWB.99


----------



## CoLdAsSauLt

Does anybody have a clue how the HP8 mk2 compares to the (OTL...) Feliks Audio Elise?


----------



## Bopper29

HP8 MKII is hooked up with Icon Audio's PS2 using Sennheiser HD600 & 700 @Low setting. Source is Pro-ject RPM 6. TT is grounded to phono. There's a little hum but of course not heard when playing except in quiet parts. The hum is caused by interconnect cable between HP8 & PS2. Has anyone come across a single ended shielded cable solution or any thoughts on how the hum can be reduced. Isn't really space to move items about. Thanks


----------



## JoeDoe

Sorry to resurrect a thread fellas, but I'm eyeballing an HP8 for my PS1000s and Alpha Primes. Anyone currently enjoying theirs with Grados? Wanting to be sure that the 32ohm rating of the PS won't be cause for intolerable noise from the Icon. Any input would be appreciated! Thanks.


----------



## Bopper29

I find hum too high on my Grado 325e even at low setting. However, I haven't got optimum placement of my gear so it's possible things could be improved. I would not write off using them. I suspect there will always be a little hum with Grado, it just depends on your tolerance levels. Sorry can't be more definitive.


----------



## Blueshound24

I haven't experienced any hum or hiss even with my sensitive IEM's. Drop dead quiet.


----------



## dreambass

I hear a tiny amount of hum at min volume on the shure 1540, I can't hear anything though even with very quiet listening.
Icon has excellent customer service speaking from experience if your concerned.


----------



## breizh

joedoe said:


> Sorry to resurrect a thread fellas, but I'm eyeballing an HP8 for my PS1000s and Alpha Primes. Anyone currently enjoying theirs with Grados? Wanting to be sure that the 32ohm rating of the PS won't be cause for intolerable noise from the Icon. Any input would be appreciated! Thanks.



Very good with either Fidelio X2 or DT880 32 ohms, no hum issues


----------



## JoeDoe

bopper29 said:


> I find hum too high on my Grado 325e even at low setting. However, I haven't got optimum placement of my gear so it's possible things could be improved. I would not write off using them. I suspect there will always be a little hum with Grado, it just depends on your tolerance levels. Sorry can't be more definitive.







blueshound24 said:


> I haven't experienced any hum or hiss even with my sensitive IEM's. Drop dead quiet.







dreambass said:


> I hear a tiny amount of hum at min volume on the shure 1540, I can't hear anything though even with very quiet listening.
> Icon has excellent customer service speaking from experience if your concerned.







breizh said:


> Very good with either Fidelio X2 or DT880 32 ohms, no hum issues




Thanks for the input fellas. May be time to pull the trigger on this guy instead of lusting after a WA22...


----------



## JoeDoe

One more Q for the jury: What other variants will the Icon take in lieu of the 6SN7? I'll admit my ignorance when it comes to understanding tube current/heater/voltage ratings, requirements, etc. Will the Icon run 6J5, 12SN7, 6DJ8, 6F8Gs? 
  
 Just trying to educate myself so I can best play with my new toy:


----------



## Jozurr

stuart1927 said:


> I just got the Icon HP8 Mk II via analogue seduction in the UK. Pretty good price v's the retailers here in the US. It has the David Shaw CV181 tubes and standard caps etc. I thought I'd share my initial impressions.
> 
> Initially, I was not crazy about the sound as it seemed  detached / distant somehow. I thought this might be due to the base Chinese 12AX7 tube, but I let things burn in for an entire weekend and wow....what a transformation! I've never heard such a massive change due to burn in! I have a lot of other gear, tube and solid state, but have never heard such a change after burn in (only 72 hrs or so). I wonder if anyone else has noticed this?
> 
> ...


 
  
 Would be really interested in your comparison of the HP8 vs the LC if you can share please


----------



## JoeDoe

Hey HP8 owners, I'm putting a few of the extra tubes I've used with it up for sale. If you mention this post, I'll offer a special bundle price for the lot. Ken Rad VT231, Genalex and JJ 12AX7s: http://www.head-fi.org/t/821134/ken-rad-vt231-cryo-genalex-12ax7b-jj-12ax7


----------



## -Darkstar-

After considering the W6 and W6SE, I decided to pull the trigger and order one of these from MD today. It was used in a photo shoot, so I got a discount. I read this entire thread and can't wait to do some tube rolling. I'll be using these with a pair of T90's and my sources are a Rega Apollo CDP and a Pro-Ject Debut Carbon DC. I've been using an original Valhalla and I wanted an amp that would be more flexible with different types of phones.


----------



## Blueshound24

-darkstar- said:


> After considering the W6 and W6SE, I decided to pull the trigger and order one of these from MD today. It was used in a photo shoot, so I got a discount. I read this entire thread and can't wait to do some tube rolling. I'll be using these with a pair of T90's and my sources are a Rega Apollo CDP and a Pro-Ject Debut Carbon DC. I've been using an original Valhalla and I wanted an amp that would be more flexible with different types of phones.


 
 Great choice! Happy listening!


----------



## louisxiawei

joedoe said:


> One more Q for the jury: What other variants will the Icon take in lieu of the 6SN7? I'll admit my ignorance when it comes to understanding tube current/heater/voltage ratings, requirements, etc. Will the Icon run 6J5, 12SN7, 6DJ8, 6F8Gs?
> 
> Just trying to educate myself so I can best play with my new toy:


 
 Hey JoeDoe, Nice setup.
  
 Got one question: Does HP8 have a pre-amp function? (i.e. if I connect it to my active speaker, will the sound get benefit from the tube sounding?) or it is just a loop out? 
  
 Hope you can help me out.


----------



## Bopper29

Hello, anyone come across a squealing noise through headphones whilst using HP8. Begins after 10 mins - any tips to resolve or are we looking at a headphone amp issue. Thanks


----------



## Triodemode

project86 said:


> Yes, I did not take that as a negative review either, just a specific sound which may or may not be a good match based on a number of factors.


 

 Really curious how would you characterize the sound of the HP8 to the Svetlana 2 that you reviewed back in 2011?


----------



## dreambass

louisxiawei said:


> Hey JoeDoe, Nice setup.
> 
> Got one question: Does HP8 have a pre-amp function? (i.e. if I connect it to my active speaker, will the sound get benefit from the tube sounding?) or it is just a loop out?
> 
> Hope you can help me out.




It's a loop out so will not pass hp8's flavour on. Would have been nice though eh.


----------



## ummon

bopper29 said:


> Hello, anyone come across a squealing noise through headphones whilst using HP8. Begins after 10 mins - any tips to resolve or are we looking at a headphone amp issue. Thanks


 
 The only thing that can create the nose, apart from the amp are the tubes itself.
 Try to test it with different tube setup and see if it changes. I had a similar problem with amp noise that was solved by changing the tubes.


----------



## CoLdAsSauLt

triodemode said:


> Really curious how would you characterize the sound of the HP8 to the Svetlana 2 that you reviewed back in 2011?




I would be interested in this too project86


----------



## stuart1927

There really is no comparison. I think the Icon is way ahead. 
  
 I haven't listened to my Icon in a while, but last weekend I spent quite a bit of time listening via my Ibasso  dx-200. Oh what a beautiful sound!
  
 The Ibasso  is using the latest sabre pro DACs,  so you are getting truly reference level input and the Icon magic leads to a sublime listening experience. I was using both my HD800's and my Ether Flows and I'd be hard pressed to pick a single flaw in the sound. 
  
 The Icon makes everything sound good....not that it glosses over details, but it does help to take the worst of the hard edges off lesser recordings. But...give it a good recording and things really start to get interesting. I listen to a lot of jazz and classical recordings...the most recent was a CD "Children of the light" by Danilo Perez, with Brian Blade and John Patitucci who are arguably one of the finest Jazz trio's of the last decade. Listening on the Icon, every track has you hooked, listening to the twists and turns and Perez's muffled groans and breathing as he plays. You really do feel part of the recording when you listen. 
  
 I've listened to this recording on the Cavali  LC and it sounds fine......but not like this.
  
 I'll need to find more time next weekend!
  
  
 sbb


----------



## BearMonster

Just found out but the Icon Audio HP8 has risen it's price.

Non Jensen cap is now £849
Jensen Cap version is now £1074

This price is definitely a blow. At the price the icon audio is just overpriced being in the 1k range the hp8 is up against Euforia, Dragon Inspire IHA-1, Auris HA2 SE. The HP8 might be able to stands it ground but it just seems saving up for the bigger boys is the better idea.


----------



## CoLdAsSauLt

BearMonster said:


> At the price the icon audio is just overpriced being in the 1k range the hp8 is up against Euforia, Dragon Inspire IHA-1, Auris HA2 SE. The HP8 might be able to stands it ground but it just seems saving up for the bigger boys is the better idea.



You think the HP8 Mk2 with Jensen caps can stand its ground against the Euforia? If yes, that's not too bad as it's more like aiming for the Elise price wise? Or am I missing something / did you miss the (double) blow of the Feliks Audio amp prices? 

What bigger boys did you have in mind exactly?


----------



## BearMonster (Feb 6, 2018)

CoLdAsSauLt said:


> You think the HP8 Mk2 with Jensen caps can stand its ground against the Euforia? If yes, that's not too bad as it's more like aiming for the Elise price wise? Or am I missing something / did you miss the (double) blow of the Feliks Audio amp prices?
> 
> What bigger boys did you have in mind exactly?



Yes i am aware of Feliks pricec range & i said might as in 50/50. The bigger boys i listed were the one's i listed but those are just some of them.


----------



## CoLdAsSauLt

BearMonster said:


> Yes i am aware of Feliks pricec range & i said might as in 50/50. The bigger boys i listed were the one's i listed but those are just some of them.



So if I understand you well, you are saying that people are better off saving up for the Euforia than buying the Elise? Have you heard both side by side? Very interested in your take on them...


----------



## Jay Smith

Got the HP8 Mk2.2 for two weeks, pair it with Beyer T1.2 and Mojo dac, it is amazing.  Compared it to Beyer A2 amp, both are good, A2 being accurate, fast, transparent, while HP8 has some magic inside,  warmth but not veil with stock tubes CV181, but the detail seems missing and the soundstage seems narrow compared to A2.  I changed the tubes to Psvane UK-6SN7 HiFi series today, after 12 hours listening, I got to say, they are well worth it, details are there, soundstage wider and more 3 dimensional, but the bass not as full as CV181 and the treble not in control perhaps they are not burn in yet..  Give them a month to burn in and I will post the results later.  BTW, I also order Genalex Gold Lion 12AX7 to replace the stock tube.....Hope it is good as Psvane.


----------



## Jay Smith

Got theTreasure CV181-Z few days ago, sounds amazing!


----------



## -Darkstar-

I'm still enjoying the EH Gold Pin 6SN7's and the Gold Lion 12AX7. I think these offer better extension in the highs and better transparency over the stock tubes, while still retaining the overall warm presentation.


----------



## Blueshound24

My HP8 has been working fine when all of a sudden the headphone jack started acting up. With the headphone plug is all the way in the jack all you can hear is the right channel. If you pull it out about 1/8" all you hear is the left channel. If you pull the headphone plug out about another 1/8" and wiggle it you can occasionally hear both channels. I have tried four different headphones with exactly the same results, and they all work fine with the three other headphone amps I have.

Has anyone ever experienced something like this and is there an easy fix for this? I have just contacted Icon Audio via their website, so probably won't here from them until sometime this week.


----------



## Jay Smith

I have the same issue in my PC, but not HP8.  Some say it may be bad contact, you can try air spray can, some say it may be loose wire inside, sorry I don't have a clue....


----------



## Nik74 (Jun 24, 2018)

-Darkstar- said:


> I'm still enjoying the EH Gold Pin 6SN7's and the Gold Lion 12AX7. I think these offer better extension in the highs and better transparency over the stock tubes, while still retaining the overall warm presentation.



Based on info here I ordered these exact tubes for my first ever tube rolling. They took 6 weeks to arrive as the Genalex in stock was not up to standard. Now to my silly question. How much do I need to pull on the tube to remove it from the amp? I just tried and it just wont come out. I tried removing the CV181s that look like they re more loosely fitted and similarly they seem to need considerale force to be pulled out of their socket. I ve never done this before- please don't laugh, there s always a first time and it can be later than usual for some of us lol- and I really dont want to accidentally damage the amp. Do I twist and pull or just pull as hard as necessary and hope for the best?


----------



## stuart1927

Nik74 said:


> Based on info here I ordered these exact tubes for my first ever tube rolling. They took 6 weeks to arrive as the Genalex in stock was not up to standard. Now to my silly question. How much do I need to pull on the tube to remove it from the amp? I just tried and it just wont come out. I tried removing the CV181s that look like they re more loosely fitted and similarly they seem to need considerale force to be pulled out of their socket. I ve never done this before- please don't laugh, there s always a first time and it can be later than usual for some of us lol- and I really dont want to accidentally damage the amp. Do I twist and pull or just pull as hard as necessary and hope for the best?


Sometimes the 12ax7's can be a little tight. Don't twist the tube as you are more likely to break it.you can rock it slightly as you pull up....this may bend the pins a bit, but they can be moved back. Usually applying gradual force and rocking slightly will get it out. Best of luck!


----------



## Nik74

Thank you! Done. Rocking left-right and up-down did it. First 10 mins of the new tubes and soundstage seems more defined, treble a tad more lit up with a slight touch of grain which I guess might clear as the tubes warm up and get burned in. Piano sounds already more realistic in timbre , very happy !


----------



## -Darkstar-

Nik74 said:


> Thank you! Done. Rocking left-right and up-down did it. First 10 mins of the new tubes and soundstage seems more defined, treble a tad more lit up with a slight touch of grain which I guess might clear as the tubes warm up and get burned in. Piano sounds already more realistic in timbre , very happy !



The treble smooths out a little but is still more lit up than the stock tubes. There also seems to be stronger bass. I'm really enjoying it with my TH900 Mk2's. I'm glad it's working out for you.


----------



## Nik74

-Darkstar- said:


> The treble smooths out a little but is still more lit up than the stock tubes. There also seems to be stronger bass. I'm really enjoying it with my TH900 Mk2's. I'm glad it's working out for you.



Last night I heard the most magical sound yet from my 800S with these. Switching to these tubes has been an unexpectedly big step up for a less than £100 upgrade.
Which makes me wonder what the thinking is behind selecting the stock tubes-apart from the fact they look nicer -
I also wonder what other sonic surprises are waiting when I decide to upgrade to the Jensen capacitors.


----------



## -Darkstar-

Nik74 said:


> Last night I heard the most magical sound yet from my 800S with these. Switching to these tubes has been an unexpectedly big step up for a less than £100 upgrade.
> Which makes me wonder what the thinking is behind selecting the stock tubes-apart from the fact they look nicer -
> I also wonder what other sonic surprises are waiting when I decide to upgrade to the Jensen capacitors.



There are posts about upgrades, further back in this thread. I'm sure that there are NOS tubes that might even sound better if you want to spend the money.


----------



## Nik74

I now have the Jensen capacitors on my desk waiting to be fitted, really excited about this. In the mean time I m using a Mullard ECC83 with the EH6SN7 and thinking I could easily live with this liquid, seductive midrange as it is. Also waiting for a Jan Ge 12AX7 and a Tungsram ECC83 so I m starting to slide down the tube rolling rabbit hole...Do any of you seasoned tube rollers have any online retailers that you would particularly recommend? I ve used tubedepot and hotrox so far and cannot say with confidence that it has been a straightforward experience....


----------



## Oscar-HiFi

Nik74 said:


> I now have the Jensen capacitors on my desk waiting to be fitted, really excited about this. In the mean time I m using a Mullard ECC83 with the EH6SN7 and thinking I could easily live with this liquid, seductive midrange as it is. Also waiting for a Jan Ge 12AX7 and a Tungsram ECC83 so I m starting to slide down the tube rolling rabbit hole...Do any of you seasoned tube rollers have any online retailers that you would particularly recommend? I ve used tubedepot and hotrox so far and cannot say with confidence that it has been a straightforward experience....



I've had great service from Langrex


----------



## Nik74 (Jul 19, 2018)

Have you guys tried a Tungsram ECC83 in the Icon? I bought one quite cheap on ebay and it's sounding quite special.Sparkly highs, smooth mids, extended bass, quite holographic, very deep and wide soundstage,i m  impressed. If anything it has  a very slight nasality as if the Icon has just recovered from a head cold. Then again I still havent replaced the capacitors so maybe this will go away when the Jensens are fitted in...


----------



## BearMonster (Sep 3, 2018)

After such a long time i decided to go back to my icon audio hp 8 after upgrading my dac.

I had no idea the bimby and icon audio hp 8 synergy was kind of slightly dissapointing. I now have the chord qutest and the synergy is so much more better. With the bimby certain tubes did not pair well the tung sol 12ax7 sounded to lean, jj ecc83 sounded too claustrophobic for me & the gold lion ecc83 would reveal the bimby grainy treble. With the Qutest the icon now gives me better soundstage, more clarity and a much better flow to the music which i have been enjoying.

I have found my ideal tubes being the ehx 6sn7 and jj ecc803s. I found the jj ecc803s compared to its other brother the ecc83 to be even more fuller in the midrange which carries that same liquidness, the sound is not enclosed but is more better spread out, treble is a bit boring, bass extends wells, and their is a certain bit more refinement to it's sounding more natural.


----------



## Nik74

Very happy to read this as I m soon getting the Qutest...  Currently listening with a Mullard ECC83 and CBS Hytron 6SN7GT s. Can't say I m missing much though  so not in a rush yet


----------



## RobertSM

Are some Head-Fiers still enjoying this amp? It's been fun to read all the postings on this amp over the years. I'm looking into this amp presently and I'm wondering how it's held up for users over the years.


----------



## Jay Smith

RobertSM said:


> Are some Head-Fiers still enjoying this amp? It's been fun to read all the postings on this amp over the years. I'm looking into this amp presently and I'm wondering how it's held up for users over the years.


Yes, I like this amp with Beyer T1.2, changing tubes can improve the sound quite a lot.  My other amp is Beyer A2, both are good, I would say vocal jazz are better with icon audio, rock music are better with A2.


----------



## RobertSM

@Jay Smith, thank you. Just wondering about your audio chain with the Icon Audio. What do you use as a source? Also do you advise on a DAC in between the source and the Icon?


----------



## Jay Smith

In my case, since T1.2 is quite revealing, I can easily hear the difference between vary kind of amp and Dac, so Dac is a must for me.  I use MacBook with Audirvana plus to play Tidal, Dac is Matrix Audio X-Sabre and Chord Mojo(less use)...


----------



## RobertSM

Gotcha. Yeah, this is on my shortlist for all tube headphone amps in this class.

I think it has a leg up for me do to the input and output tubes used. Very well regarded, blue chip tubes. From NOS to newly produced, the tube options for this amp are many.


----------



## Nik74 (Dec 1, 2018)

I find it a fantastic combo with my 800S. And it responds so well to tube rolling ! Currently I have gone back to Electro Harmonix gold pin 6Sn7s driven by a Tungsram ECC83. I was lovign the Hytron 6SN7s but with these headphones the soundstage was unrealistically wide, the EH contain it a bit more and add depth


----------



## Nik74

I d be interested to know what tube combinations  users of the Icon have settled on. I m guessing most of current users have had the amp for a while ?


----------



## Jay Smith

I have Shuguang treasure cv181-z and Psvane UK-6SN7 HIFI series, finally settle with Shuguang.


----------



## -Darkstar-

I'm still enjoying mine with my Fostex TH900 MK2's. I've found this combo to be highly resolving and dynamic sounding. I settled on EH Gold pin 6sn7's and a Gold Lion 12ax7. I think these tubes extended the highs, improved clarity in the midrange and added more impact in the bass over the stock tubes.


----------



## Nik74

I like the Gold Lion too. I had exactly your combination of tubes just before I upgraded the capacitors. Then in the meantime I got those other tubes so I rolled other combinations, I ll try the Gold Lion again with the EH soon. I still have a Mullard MC1 and a JAN GE that I havent rolled.


----------



## -Darkstar-

This amp definitely responds to tube rolling. I'm glad they used common tubes. I think the 6SN7 is one of the better tubes out there. I've used EH 6SN7's in Cary Audio preamps in the past with great satisfaction.


----------



## RobertSM

Well I've joined the club here with this Icon Audio headphone amp. I found a lightly used standard model from a retired man who is really downsizing his system after a life long love affair with audio.

After reading over the thread, I went ahead and brought a set of Mundorf Supreme Mcaps, silver/oil caps to upgrade. I have the amp at a respected amp repair shop having the caps being soldered in and having the amp tech giving it a good look over to see if it needs anymore love.

I'll deal with the tubes and what I've bought when I get this back.

Might be a couple of weeks before it gets on the bench and gets returned to me. Looking forward to sharing my thoughts.

Big thank you to those that have shared over the years. Your recommendations were noted and made it easy for someone like me to come in and learn from what's worked for others in years past.


----------



## Nik74

RobertSM said:


> I went ahead and brought a set of Mundorf Supreme Mcaps, silver/oil caps to upgrade.



Great idea to first upgrade the capacitors as the difference they make in sq is substantial, they elevate this amp to the next level imho.
Do you remember the characteristics of the caps you ordered? Asking this because when I ordered mine , the values that Icon Audio provided were different to the ones discussed here and did perplex the engineer that undertook their fitting 
In any case, looking forward to your impressions 
N


----------



## RobertSM

@Nik74, I ordered the 0.33uF 1000Vdc caps. Hoping these will do the trick.

Just curious, did you upgrade the caps in your unit? If so do you mind sharing the brand, make and model of the caps. Also the values. Thanks.


----------



## Nik74

@RobertSM  I did upgrade the capacitors a couple of months after buying the amplifier so can wholeheartedly say that the upgrade is a game changer for this amp. Like many people have already mentioned the stock caps are a bottleneck - so is the stock driver tube but that’s a whole other story. 

I emailed Icon Audio and ordered the capacitors that they recommend directly from them . Those were Jensen  copper foil paper in oil caps and the values were 0.1uf 630V , quite different to yours as I imagined ...I know nothing about the technicalities but my engineer found the values bizarre so got in touch with them to double check that these were indeed the right ones. Icon confirmed they  were and offered an explanation that I don’t remember - again I lack the technical familiarity so didn’t care as long as it was right -. 
I hope this is helpful but in any case I strongly suggest that you email or call them , they are very responsive and friendly
N


----------



## RobertSM

@Nik74, thank you. I'll email then straight away. Better to be sure.


----------



## RobertSM

@Nik74, emailed and already received a reply from Icon. You are right, the correct value is .1uF. I may use a capacitor rated 1000Vdc but was told to absolutely use the value of .1uf.

So, now I've ordered the correct caps. A bit of a bummer that I ordered the wrong caps. But I'll hold on to them, maybe I can use them in another project.

Again, thanks for the heads up.


----------



## Nik74

I have found this forum a source of great help and advice so it’s a pleasure to be able to help too 
Looking forward to your impressions 

Just make sure to get rid off the stock 12AX7 and find a nice Mullard mc1 or gold lion 12AX7 or even a Tungsram ECC83


----------



## RobertSM (Jan 11, 2019)

Ok, got the correct capacitors soldered in. Stuck with the Mundorf Mcap supreme silver oil. Presently, burning in a pair of the new Sophia electric 6sn7 blue glass tubes and a 12ax7 also from Sophia.

I'm about 25 hours into the caps & tubes burn-in. Very much impressed with what I hear so far. Great detail and air to the sound signature. I know the term gets used alot, but I find this Icon Audio HP amp to be very musical. Also, I'm impressed with how black the amp is. Totally silent. Like, I hear zero distortion. In regards to power, this solidly built, hefty little amp has plenty of power. No issues at all driving my Sennheiser HD-6XX headphones with authority. Also, I did read a few prior comments regarding transformer noise/hum. I'm thankful that my unit is totally quite.

More to come as I get used to the amp and post caps and tubes burn-in. But this is really turning out to be a great amp.


----------



## Nik74

That is great to hear ! 
I m curious about your tube choices, I ve read about the Sophia 300B but didn’t know they also did 6SN7 and 12AX7, will do some research. 
I m guessing your HP8 will need another 80 hours before it shows its true character


----------



## RobertSM

@Nik74 

These are the newer design for Sophia. Apparently the original clear glass 6sn7 tubes had some problems. The blue glass tubes represent Sophia addressing those concerns.

Here is a photo. They do look a bit different...the blue glass and all.


----------



## Nik74

Wow they so much bigger than my electroharmonix !
I love the blue colour


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## RobertSM (Jan 11, 2019)

The folks at Sophia electric say these use a 'coke bottle' shape. The tubes are priced by grade; A,B & C- grade. I sprung for a matched pair of the grade A.  I'll share as they work through the burn-in period.


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## hood177 (May 23, 2019)

Hi all,
what about modding?
This is my ICON AUDIO HP8 MK2 Russian Bear Edition....  
	

	
	
		
		

		
		
	


	



All that installed is seen in the photo:
- New ceramic vacuum tube sockets - it all started with the need to replace them 
	

	
	
		
		

		
		
	


	



- new large aluminum plate
- top-level volume control TKD Ko-on 2CP-2511 50K
- Jupiter HT Beeswax Paper Foil Cryo interstage capacitors with bee-wax impregnated paper dielectric
- Capacitors of increased capacity in the power supply circuits Vishay and Cornell Dubilier SLP
- capacitors of increased capacity in cathode circuits Elna Cerafine
- 2W TKD Correctohm Metal Film and Kiwame resistors, Jantzen metal-ceramic
- diode bridges with ultra-fast diodes Vishay BYV26E-TAP and ON Semiconductor MUR420RLG
- CMC-803-F Gold plated RCA connectors

Soldering with WBT-0800 4% silver solder.





ICON AUDIO HP8 MKII Russian Bear Edition
SIEMENS ECC83 + Philips ECG JAN 6SN7WGTA (6Н8С)




ICON AUDIO HP8 MKII Russian Bear Edition


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## RobertSM (Apr 7, 2019)

@hood177, looks amazing. I do have a couple of questions.

1. Looks like you removed the copper plate from the top and added a plate of metal that now totally covers the amp. What material did you choose?

2. How do you like the upgraded coupling/interstate capacitors? You choose a Juniper cap. I went with a Mundorf silver in oil. Wondering on the effect.

3. What tubes are you currently using? I moved away from the Sophia tubes shown in my last picture. I'm currently running, Siemens Halske 12AX7 produced in 1968. I was using a Mazda France 12AX7 from the mid 1960's which has a beautiful top-end sparkle and air but didnt give me the extremely wide bandwidth that the Siemens gave me. I'm also very happy with my Sylvania GTA 6SN7, these are the chrome dome tubes.

Either way, good work in the mods. Please share on how it's all working out for you.


----------



## hood177 (Apr 4, 2019)

Hi* RobertSM*,
thank you for rating.  
I have already modified it twice.
1. Upper plate - anodized aluminum. Original plate - anodized aluminum too, not copper.
2. Jupiter HT caps - they are superior. I tested different and I like Jupiter more than others.
3. I have many different NOS 12AX7 and 6SN7 tubes and new Psvane Treasure 12AX7 LS Special Edition + Psvane CV181-TII ‘grey bottle’.
SIEMENS ECC83 + Philips ECG JAN 6SN7WGTA on the photo.


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## hood177 (Apr 9, 2019)

MAZDA by Telefunken 12AX7 + Psvane CV181-TII ‘grey bottle’ on the photo.






ICON AUDIO HP8 MK2 Russian Bear Edition


----------



## hood177

Thread is dead.
No more enthusiasts for Icon HP8?


----------



## Nik74

People are busy enjoying it most probably


----------



## Blueshound24

Well the HP8 just works and is one fine amp. Nothing I have had has bettered it and I'm very happy with mine. I'll bet there are many content silent owners out there.


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## hood177 (Apr 15, 2019)

Blueshound24 said:


> Well the HP8 just works and is one fine amp. Nothing I have had has bettered it and I'm very happy with mine. I'll bet there are many content silent owners out there.


Where are the updates, modifications and improvements? 
For several years, I modified a couple of my Icons three times.
Electrolytic and oil capacitors are tired of the heat and this is a reason for new modifications.


----------



## Blueshound24

I'm not much of a modder. Usually just happy with whatever I choose to keep in my system. If it is not to my liking i will just buy something else rather than try to change it.


----------



## Nik74

Blueshound24 said:


> I'm not much of a modder. Usually just happy with whatever I choose to keep in my system. If it is not to my liking i will just buy something else rather than try to change it.



Very much the same here. If you haven’t had the Jensen capacitor upgrade though - offered by Icon Audio but easily undertaken by your local audio engineer- , that is a strongly recommended step to getting the most of the HP8.


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## RobertSM (Apr 15, 2019)

I use my HP8 MK2 almost daily. I've found alot of enjoyment with upgraded capacitors and NOS tubes. Specifically, I find that the ECC83/12AX7 input tube of the HP8 MK2 has a big impact on overall sound. Presently, I rotate between a Siemens NOS tube and a Mazda France tube. To me the Siemens offers a fuller bandwidth spectrum and a little more overall gain. The Mazda, a really pretty top end with great air and sparkle.


----------



## -Darkstar-

Nothing really to update on. I'm enjoying mine with my Fostex TH900 Mk2's. Just a solid all around amp and I have no real desire to change it out for something else.


----------



## Jay Smith

Last month I had consistent static noise in my HP8 mk2,  and recently I figure it out the noise came from my new D-link home plugs, but my Beyer A2 amp does not have that static noise, I guess tube may be more sensitive to those high frequency noise.  Now, I am enjoying HP8 with T1.2 again, it is a good amp.


----------



## hood177 (Apr 16, 2019)

-Darkstar- said:


> Nothing really to update on.


Probably you have not yet heard the real sound of the Icon......  
Like any tube amps, Icon HP8 has great potential for improvement.


----------



## MLGrado (Jun 20, 2019)

Mine is dead.  Enjoyed for over 2 years.  No mods but lots of tube rolling.  I own over 100 vintage 6SN7 types and several hundred vintage 12AX7 types from every factory you can imagine.  Telefunken to Mullard, all the Phillips factories, all the varied French tubes and even several 1948 NOS RCA 12AX7 that are some of the very first made period.  Even have General Electric/Ken Rad factory engineering samples that are also late 40s!!


Anyway I killed a socket most likely via tube rolling.  I started getting some noise I attributed to the tubes, and on the very next roll something ‘gave’ in the 12AX7 socket and now there is a major hum.

Took bottom access panel off, and all looks correct, but moving the tube in the ‘AX7 socket causes just a bit of movement in the parts array  below the socket making a ‘spring-like’ sound that wasn’t there before.  It looks like one of the socket   Leads moves too much.  More give than normal. 

So I suspect all the sudden noise problems was never a tube, and I made it worse with one final tube roll that damaged the socket internals that connect tube pin to leads below. 


Icon Audio referred me to the authorized dealer in US for repair.  Of course Music Direct. 

Music Direct won’t service it, though since I did not purchase it from them.  Both Icon and MD suggested I find a local repairman.  I have yet to have any luck after several promising looking options have not returned my calls yet. 

MD DID give me the phone number to the repair center in Chicago that does all of their repair and upgrade work on Icon Amps.  I haven’t called them yet. 

My other option is of course do it myself. I have all the necessary tools including a pro variable solder station and I have what I would call average skill.  But that scares me a bit. 

Anyway I am doing the cap upgrade too but am confused by the values as well being quoted by Icon for the coupling caps.  The value on the Solen MKP caps is specifically 0.33uF 630v.  That’s not what folks are being told about the Jensen upgrade, though.  The tech at MD did tell me the stock caps in the Hp8 MKII do NOT measure at their rated specs.  Maybe that has something to do with it.


Finally, does anyone have a recommendation for a tech?  Before I send to Chicago where it could sit for quite awhile low on priority list, or before I fire up my own equipment??

Thanks!


----------



## Blueshound24

MLGrado said:


> Mine is dead.  Enjoyed for over 2 years.  No mods but lots of tube rolling.  I own over 100 vintage 6SN7 types and several hundred vintage 12AX7 types from every factory you can imagine.  Telefunken to Mullard, all the Phillips factories, all the varied French tubes and even several 1948 NOS RCA 12AX7 that are some of the very first made period.  Even have General Electric/Ken Rad factory engineering samples that are also late 40s!!
> 
> 
> Anyway I killed a socket most likely via tube rolling.  I started getting some noise I attributed to the tubes, and on the very next roll something ‘gave’ in the 12AX7 socket and now there is a major hum.
> ...




I would like to know too for some needed repairs.


----------



## hood177 (Jun 24, 2019)

MLGrado said:


> Finally, does anyone have a recommendation for a tech?


I highly recommend leaving the capacity of capacitors 0.33uF 630v. It is also necessary to double the capacity of all cathode capacitors. And the sound of the Icon will be at the highest level.
And use only ceramic sockets. Teflon sockets are very soft and quickly deformed.


----------



## MLGrado

RobertSM said:


> Ok, got the correct capacitors soldered in. Stuck with the Mundorf Mcap supreme silver oil. Presently, burning in a pair of the new Sophia electric 6sn7 blue glass tubes and a 12ax7 also from Sophia.
> 
> I'm about 25 hours into the caps & tubes burn-in. Very much impressed with what I hear so far. Great detail and air to the sound signature. I know the term gets used alot, but I find this Icon Audio HP amp to be very musical. Also, I'm impressed with how black the amp is. Totally silent. Like, I hear zero distortion. In regards to power, this solidly built, hefty little amp has plenty of power. No issues at all driving my Sennheiser HD-6XX headphones with authority. Also, I did read a few prior comments regarding transformer noise/hum. I'm thankful that my unit is totally quite.
> 
> More to come as I get used to the amp and post caps and tubes burn-in. But this is really turning out to be a great amp.




Hi,

How goes your amp these days???  I actually ordered a brand new one and I just got it today from MD Chicago.  I still have my 'wounded' one on the bench and I am slowly working through the process of changing the 9 pin ceramic socket.  

My real question again is about the coupling caps.  I am not going to touch the new amp; it sounded really poor at first, but after several hours is settling in nicely.  Tube rolling makes a major change.  I am using what I think are about the best 6SN7 types... they are actually 6F8G Tung Sol with adapters.  Just makes an AMAZING difference over the stock tubes.  Right now have an RCA 5751 black plate triple mica in the pre spot.. nice, nice tube.  Not my best, but I have kind of a fondness for it.  Anyway, I digresss..


I KNOW the difference tube rolling makes.  I am really curious how much difference the cap upgrade makes.  I bought the Jensen .1 630v as many of you say Icon recommended, but I am thinking of getting a pair of the .33uf as well, since that is clearly the value of the stock caps.  Anyone have a summary of the reason Icon is giving for the value change?  My research says that the biggest difference will be in the bass output, as in LESS bass going to a smaller value cap.  

Just curious, and wanting to kind of stir up some talk about this great amp that seems like a lot of people just enjoy and leave it at that!  Rarely do you find these second hand.  People must just be holding onto them and enjoying.  In any case, I hope they have at least tried tube rolling.  And as for myself, I am afraid I am about to jump down another rabbit hole with caps... ph my.


----------



## MLGrado

Well, as I said above I now own two of these babies.  The first one I bought that is now being serviced was already used.  I can say the brand new model I just installed certainly looks sharper, has even less a noise floor.. black as black background, no occasional anomalous noises, and according to the technician check sheet has even better channel balance.  

I get the impression Icon is constantly evaluating and improving its product in an organic fashion, not saving little changes for major reissues or new editions.  

After 20 hours of break-in this one sounds GREAT even with stock caps.  But I won’t fully enjoy it until I finish the repair of my original HP8 MKII.  


Here’s the new kiddo.. she’s a beaut.  Running a late 1950’s RCA 5751 black plate triple mica along with pair of WWII era Tung Sol VT-99 / 6F8G.

Oh and I’m not as stupid as last time; I have my socket saver in the 9 pin socket.


----------



## RobertSM (Jul 12, 2019)

MLGrado said:


> Well, as I said above I now own two of these babies.  The first one I bought that is now being serviced was already used.  I can say the brand new model I just installed certainly looks sharper, has even less a noise floor.. black as black background, no occasional anomalous noises, and according to the technician check sheet has even better channel balance.
> 
> I get the impression Icon is constantly evaluating and improving its product in an organic fashion, not saving little changes for major reissues or new editions.
> 
> ...



Beautiful!  So, I'll share a bit about my Icon HP amp.

It's treating me very well. As I previously stated, I did do a coupling capacitor upgrade. I went out and bought a good quality Mundorf silver in oil cap and took it to a local shop to have the caps soldered in. The engineer saved the stock caps so I could see the difference. The stock caps were the size of navy beans. Very small. The caps that I replaced them with 3 times the size. I asked the engineer about this difference and he thought that this was surely a good upgrade to make. He believed that the stock caps would be a point of congestion and the new caps would allow for more current flow and more importantly a better sound.

Tube wise, I first began with a Chinese made 6SN7 by Sophia. I think the tube was ok but I found the sound to be grainy. After a few months I decided to venture out into the world of NOS tubes and bought a pair of Sylvania tubes from the late 50's. I also upgraded the 12AX7/ECC83 tube to a Mazda France tube, silver anode, from the mid 60"s. This is what I'm currently running and I'm very happy. A full warm sound, not too lush. Very detailed and focused.

Which brings me to ask a question of you.

How do you like these tube equivalents? I was totally unaware that the S6N7 could be changed out for another tube. I'm also noticing the tall bottle. How does this upgrade effect the sound?  I'm very  interested in hearing your thoughts. Also, would you share what parts are involved in your tube upgrade? If I wanted to try this out myself, what equipment would I need to seek out?


----------



## MLGrado (Jul 13, 2019)

RobertSM said:


> Beautiful!  So, I'll share a bit about my Icon HP amp.
> 
> It's treating me very well. As I previously stated, I did do a coupling capacitor upgrade. I went out and bought a good quality Mundorf silver in oil cap and took it to a local shop to have the caps soldered in. The engineer saved the stock caps so I could see the difference. The stock caps were the size of navy beans. Very small. The caps that I replaced them with 3 times the size. I asked the engineer about this difference and he thought that this was surely a good upgrade to make. He believed that the stock caps would be a point of congestion and the new caps would allow for more current flow and more importantly a better sound.
> 
> ...



Yes you can run 6SN7 equivalents.  For excellent sound that costs very little, check out the Russian 6h8c / 6N8S tubes.  Stay in the 1950's and 60's though.  Meltz versions are the expensive rare highly sought versions, but I use tubes made in the Russian 'FOTON' factory from the 1950's.  You can get a dozen true NOS package seals never been broken for 20 bucks.  These Russian tubes are the exact equivalent to American 6SN7.

The predecessor to the 6SN7 here is the US in the 6F8G.  They are essentially the same tubes spec-wise.  They are much larger physically, and have the ground pin is on top of the tube.  Adapters to use these in the 6SN7 slot are ubiquitous on eBay.  Only downside to the adapters is they come from China and make take a few extra days of shipment. 


When everyone was going crazy over 6SN7, sending the prices through the roof for NOS, savvy tube collectors were grabbing up the 6F8G.  Unfortunately, the collecting world caught up, and now the 6F8G has gotten much more rare and expensive.  But for my ear, they are preferable to the 6SN7.  The still have all the tubey goodness of the 6SN7, but seem to possess a bit more sparkle up top and make for a more 'live' sounding stage.  They also seem to be a bit better at micro detail; delineating mid-range detail on a tick higher level.

I own lots of top notch 6SN7 and 6F8G.  My favorites of each are the World War II era versions.  Which means look for their military designations... VT-231 for 6SN7 and VT-99 for 6F8G.

RCA is a reasonable jump on spot for 6F8G.  Sylvania ones sound nice, too.  The most coveted, similar to the 6SN7 collectors, is the Tung Sol VT-99.  They come with a couple different plate styles, but as long as they are the same in both spots, I don't fret over that as long as they are well matched and both VT-99.  It may take a couple C bills or more to get into Tung Sol. 

But again, RCA sounds great and you can get a nice pair of VT-99 for under $100. 

Other ones that are rare but sound good are National Union and Ken Rad.  Both in good shape (especially two reasonably well matched examples) are getting harder and harder to come by. 


Now on the flip side, some issues you may run into with them is poor grounding/noise and microphonics.  The next generation 6SN7 was improved in both regards.


----------



## alvin sawdust (Oct 15, 2019)

Has anyone else spotted a new headphone amp from Icon:

https://iconaudio.com/hp-205d-headphone-amplifier-hp-205d

Uses the unusual looking 205d DHT tube.
Price is £3k.


----------



## RobertSM

This is news to me.  Interesting.


----------



## alvin sawdust

RobertSM said:


> This is news to me.  Interesting.


I found out after the event that they had it on display at the UK Northwest audio show, wish I'd gone along now. Can't find any reviews or user comments about it anywhere.


----------



## dreambass

I was looking at the integrated valve amp's on the website and see that, bet it's bliss. The HP8 is missed I loved it


----------



## 340519

Hey guys, I just bought an HP8 and it is downright fantastic paired with my benchmark dac2 and the sennheiser hd800 and hd800S. Loving it. I also bought three different 12AX7s from the tubestore for some rolling fun. Now back to peter gabriel's secret world...


----------



## Jay Smith

dmdm said:


> Hey guys, I just bought an HP8 and it is downright fantastic paired with my benchmark dac2 and the sennheiser hd800 and hd800S. Loving it. I also bought three different 12AX7s from the tubestore for some rolling fun. Now back to peter gabriel's secret world...



I also like my HP8 mkii very much.
I use ShuGuang Treasure vacuum tubes CV181-Z and the sound is rich, full body but not sluggish with good sense of soundstage and impact, which is better than the stock tubes.  Compared to my other set of Psvane UK-6SN7 HiFi series tubes, HiFi series give sound like transistor more on the lean side which may suit some orchestra music.


----------



## 340519

Jay Smith said:


> I also like my HP8 mkii very much.
> I use ShuGuang Treasure vacuum tubes CV181-Z and the sound is rich, full body but not sluggish with good sense of soundstage and impact, which is better than the stock tubes.  Compared to my other set of Psvane UK-6SN7 HiFi series tubes, HiFi series give sound like transistor more on the lean side which may suit some orchestra music.


Where did you pick up your tubes? I'd like to order some online.


----------



## 340519




----------



## Jay Smith

dmdm said:


> Where did you pick up your tubes? I'd like to order some online.



I bought them from China online store Taobao but you can also try below Amazon links:

Shuguang Treasure Cv181-z Vacuum Tube Matched Pair Replace Cv181 Cv181-t 6sn7
by Salience Hi-Fi Audio
Learn more: https://www.amazon.com/dp/B011QZ4N1O/ref=cm_sw_em_r_mt_dp_U_O6.1DbDYQ8PH6

Matched Pair Psvane UK-6SN7 HIFI series Vacuum Tubes
by Salience Hi-Fi Audio
Learn more: https://www.amazon.com/dp/B00N9T5ZHW/ref=cm_sw_em_r_mt_dp_U_Wda2DbEQTSBYM


----------



## 340519

Jay Smith said:


> I bought them from China online store Taobao but you can also try below Amazon links:
> 
> Shuguang Treasure Cv181-z Vacuum Tube Matched Pair Replace Cv181 Cv181-t 6sn7
> by Salience Hi-Fi Audio
> ...


I spent enough for now, but I've bookmarked the amazon page. Thank you.


----------



## 340519 (Nov 27, 2019)

And wow the stock hd800 sounds incredible with this amp. That 6khz spike is tamed. Very nice.


----------



## stuart1927

Yes I've always liked this amp with my HD 800 phones. I need to use this amp more, it's been neglected for a while. I have a really nice stash of tubes for this amp as well so one night, I'll need to get re-aquainted with the amp. Part of the problem is that I have a really nice DNA stratus amp too, so that tends to get most use. 

I really do like the Icon though....it is a very nice amp that brings something different to the table.


----------



## rodrigaj

New Icon HP8 MKII owner here with HD800S phones.

For those of you using the HP8 with Sennheiser HD800 phones -  is the consensus that the mid setting for impedance is best?


----------



## 340519

rodrigaj said:


> New Icon HP8 MKII owner here with HD800S phones.
> 
> For those of you using the HP8 with Sennheiser HD800 phones -  is the consensus that the mid setting for impedance is best?


Nah, I like either low or high with the 800 and S actually. I texted the technician Don Stewart, and he said pick whichever one you like. To quote him:
it allows a flexible match to the various products that will be connected, use which ever you find provides the optimum performance


----------



## shabta

I have been a happy owner of the Icon for some years. I had  the caps upgraded, which is a little better. I think it's a great match with the HD800S. I prefer the mid setting for impedance. The bass is a little stronger at the hi setting. But a little amp distortion is also noticeable.


----------



## shabta

dmdm said:


> Nah, I like either low or high with the 800 and S actually. I texted the technician Don Stewart, and he said pick whichever one you like. To quote him:
> it allows a flexible match to the various products that will be connected, use which ever you find provides the optimum performance



LOL so there you have it, no consensus. But me, myself and I all agree, mid is best for hd800 & S


----------



## CoLdAsSauLt

What does that knob change actually? Gain, but also output impedance?


----------



## RobertSM (Sep 20, 2022)

I'm also a Icon Audio HP8 MKII owner for the last year. I love it.

A few comments and things I've learned.

I upgraded the caps. I had a tech install a nice pair of Mundorf silver oil caps that I purchased. The difference was huge. As has been said here in the thread over the years, the cap upgrade really opens everything up. Regardless of what brand of capacitors you decide on, it's a worthwhile expense.

I've played around with NOS tubes, currently running a great Telefunken 12AX7 from the mid 1960's. This tube seems to have added a level of strength in gain and really seems to have increased the bandwidth. All frequencys are represented evenly. A very linear tube.

For output tubes, I use a matched pair of Sylvania 6SN7 GT from the mid 1950's. I got these for about $40.00-45.00 for the pair. They are noted to be very clean and linear. They dont offer a fat warm sound like you'd get from a vintage RCA. But I was really after a cleaner sound.

Also, I'd like to mention that in my experience the amp likes to be warmed up for a good 15-20mins. Its like most tube amps that really require and really shine most when you let them warm up.

That's all for me.

Any other owners have any thoughts, tips or tricks as to how they enjoy their amp please let us know.

Happy listening.


----------



## 340519

shabta said:


> I have been a happy owner of the Icon for some years. I had  the caps upgraded, which is a little better. I think it's a great match with the HD800S. I prefer the mid setting for impedance. The bass is a little stronger at the hi setting. But a little amp distortion is also noticeable.


I will listen for that. I just bought eq pro last night for my PC, so I've boosted the bass 6db below 100hz, and now the 800 and S have satisfying bass to my ears.


----------



## 340519

As a side note, Don told me that David Shaw personally tuned my unit with tubes he carried over from the UK. I gotta say the thing sounds fabulous.


----------



## 340519

Painterspal said:


> Great to see your review project86. I've been putting some thoughts together on the Icon too, but it'll be very boring because I agree with you completely. Oh well!
> 
> I'm still loving my Icon and have settled on what I think is an outstanding tube combination: Shuguang Treasure CV181Z and Mullard MC1. It's a perfect balance between insight and euphony. Combined with my HD800 it's pure bliss.
> 
> ...


Nice. I've saved those tubes on Ebay.  Going to pick some up soon.


----------



## 340519

Do you all let the tubes warm up for a while before listening?


----------



## Nik74

dmdm said:


> Do you all let the tubes warm up for a while before listening?



To my ears they bloom after about an hour, so yes. On the other hand I really enjoy listening within minutes after switching on to hear how the sound gradually opens up, it often helps me get completely immersed.


----------



## 340519

Nik74 said:


> To my ears they bloom after about an hour, so yes. On the other hand I really enjoy listening within minutes after switching on to hear how the sound gradually opens up, it often helps me get completely immersed.


Cool thanks.


----------



## rodrigaj

My dac is a Lumin A1. It has a software volume switch accessed via the Lumin App on my iPad. I currently set it to 100% and use the Icon HP8 for final volume. As such, the Icon volume knob is usually at the 9 - 8 o'clock position as a result. So, what is the consensus - do I reduce the Lumin volume and turn up the Icon volume to the 2 o'clock position? Just curious what the thinking is. I've tried it both ways and I think that I get better inner detail when the Icon is set up and the Lumin is set down. But I can't really say for certain.


----------



## RobertSM

rodrigaj said:


> My dac is a Lumin A1. It has a software volume switch accessed via the Lumin App on my iPad. I currently set it to 100% and use the Icon HP8 for final volume. As such, the Icon volume knob is usually at the 9 - 8 o'clock position as a result. So, what is the consensus - do I reduce the Lumin volume and turn up the Icon volume to the 2 o'clock position? Just curious what the thinking is. I've tried it both ways and I think that I get better inner detail when the Icon is set up and the Lumin is set down. But I can't really say for certain.




Generally speaking, with DACs you want your volume on max. This will insure a full digital bit perfect signal with maximum voltage will make it downstream so your next component(in this case the Icon).


----------



## 340519

rodrigaj said:


> My dac is a Lumin A1. It has a software volume switch accessed via the Lumin App on my iPad. I currently set it to 100% and use the Icon HP8 for final volume. As such, the Icon volume knob is usually at the 9 - 8 o'clock position as a result. So, what is the consensus - do I reduce the Lumin volume and turn up the Icon volume to the 2 o'clock position? Just curious what the thinking is. I've tried it both ways and I think that I get better inner detail when the Icon is set up and the Lumin is set down. But I can't really say for certain.


I put my benchmark on ht bypass which sets the volume knob automatically to the 3 o'clock position on the dac. Rory Rall of benchmark told me this is the proper method when sending the signal to an integrated like the hp8.


----------



## 340519 (Nov 25, 2019)

Well guys, with the bass boosted under 100hz with the eq and the gold lion 12AX7 I'm in heaven. I couldn't stop listening.  I'm floored by how good this amp is. I'm officially a tube headphone convert.
Edit: I received the .5 meter kimber silver streak today as well which is between the benchmark and hp8. Simply glorious sounding.

So what is the best 12AX7 out there to put in the icon? The gold lion  is so good I want to keep going.


----------



## stuart1927

The gold lion tubes are very good. Certainly as far as new tubes go, they are as good as any and very reliable, based on my experience..

The NOS options for 12ax7'are almost endless, but my favourite tube with this amp is a 60's Telefunken Tube that I picked up a few years ago (actually a pair) 

Second would be a tungsram. I have a pair of these from I believe the early 70s, and they are almost as good as the Telefunken. 

It's not night and day Vs the gold lion, but they just offer something more in terms of clarity/ midrange and bass. I find them especially great for classical music or jazz. 

Another great tube is a vintage Millard cv4004 (12ax7).

Upscale audio carry most of these tubes and have some great write ups and videos explaining some of the characteristics if you haven't already visited the site. 

Happy listening

Stuart


----------



## 340519

stuart1927 said:


> The gold lion tubes are very good. Certainly as far as new tubes go, they are as good as any and very reliable, based on my experience..
> 
> The NOS options for 12ax7'are almost endless, but my favourite tube with this amp is a 60's Telefunken Tube that I picked up a few years ago (actually a pair)
> 
> ...


Thanks Stuart. Well, looking at those other tubes, the gold lion is definitely the cheapest and it sounds fantastic.


----------



## stuart1927

Like most things, it's the law of diminishing returns for sure. A few years ago I spent a small fortune on NOS tubes for my amps. It was when I was on an expat assignment to the US, so had quite a bit more cash than I have now! 

I'm actually more focused on value hifi these days, and seek out high quality and less known products...mainly from China. I've just bought a Kingko amp from Hong Kong that I'm really excited about. It's actually a push/pull integrated amp that uses el84 tubes. It has 12 w per channel so you can drive efficient speakers but it also has a killer headphone amp on board too. I left my icon in the UK so needed to build a system here in China where I'll be spending half my time!


----------



## Nik74

stuart1927 said:


> Like most things, it's the law of diminishing returns for sure. A few years ago I spent a small fortune on NOS tubes for my amps. It was when I was on an expat assignment to the US, so had quite a bit more cash than I have now!
> 
> I'm actually more focused on value hifi these days, and seek out high quality and less known products...mainly from China. I've just bought a Kingko amp from Hong Kong that I'm really excited about. It's actually a push/pull integrated amp that uses el84 tubes. It has 12 w per channel so you can drive efficient speakers but it also has a killer headphone amp on board too. I left my icon in the UK so needed to build a system here in China where I'll be spending half my time!



I m noticing very similar taste in valve preferences  so I d like to ask what your preference on the EL84s lies towards. I also run a really good EL84 amp as a head amp and overall so far it’s again the Gold Lion that do the trick. I ve tried some Siemens too, they sounded good for about 200 hours and then lost their magic, could have had been used or who knows ...


----------



## stuart1927

Nik74 said:


> I m noticing very similar taste in valve preferences  so I d like to ask what your preference on the EL84s lies towards. I also run a really good EL84 amp as a head amp and overall so far it’s again the Gold Lion that do the trick. I ve tried some Siemens too, they sounded good for about 200 hours and then lost their magic, could have had been used or who knows ...



For me again it was the Telefunken El84's. I got a NOS pair for a Doge 6210 headphone amp and the sound out of that cheap little amp was frankly sublime. Unfortunately the Doge died! Not the fault of the amp....it was a 115v unit that I got in the US and I fed it 230v by mistake!

Anyway, fortunately I didn't have the Telefunkens in place when that happened as they cost more than the amp. 

I sourced about 10 EL84's marked "EI" around the same time. These were apparently made in the Telefunken factory and look very similar in terms of tube architecture. These certainly sound similar to the Telefunken's. That's why I was on the lookout for an EL84 amp as I wanted a home for the tubes! The Kingko amp takes 4 of them.

I haven't tried any other EL84's yet, but I would certainly try the gold lions as they are great tubes at a fair price. 

Stuart


----------



## 340519

I have to say I'm a newbie around tubes  but I've had high end systems for over 30 years, and the gold lions sound simply outstanding to me.


----------



## stuart1927

My bad....the EI tubes I mentioned above were actually from the Tungsram factory....not Telefunken. The Tungsram EL84's are also rated as amongst the very best out there.


----------



## 340519

-Darkstar- said:


> I'm still enjoying mine with my Fostex TH900 MK2's. I've found this combo to be highly resolving and dynamic sounding. I settled on EH Gold pin 6sn7's and a Gold Lion 12ax7. I think these tubes extended the highs, improved clarity in the midrange and added more impact in the bass over the stock tubes.


Are you talking about the 
*ELECTRO-HARMONIX 6SN7 GOLD?*
*https://www.thetubestore.com/electro-harmonix-6sn7-gold*


----------



## 340519

Well fellas, I ordered 2 of the EH Gold 6sn7 matched and balanced listed above. Done and done.


----------



## -Darkstar-

dmdm said:


> Are you talking about the
> *ELECTRO-HARMONIX 6SN7 GOLD?
> https://www.thetubestore.com/electro-harmonix-6sn7-gold*


 
Yes. For new stock 6SN7's, I like EH. I used them for years when I had Cary Audio preamps. I hope they work out for you.


----------



## Nik74

stuart1927 said:


> My bad....the EI tubes I mentioned above were actually from the Tungsram factory....not Telefunken. The Tungsram EL84's are also rated as amongst the very best out there.



I have a Tungsram ECC83 that I agree sounds reminiscent of Telefunken so I d be very keen on trying their EL84s. One of my Gold Lion EL84s spectacularly died on the weekend so I m using a quad of Siemens that sound wonderful and very extended and solid down in the sub 100hz region!


----------



## 340519

I have a new pair of audeze lcd-xc on the way. I'm very excited to hear them with the hp8!


----------



## 340519

New cans for the hp8!


----------



## Nik74

Is it a good match ?


----------



## Nik74

Anyone in here with expert knowledge of ECC83 variants? My Ebay is inundated with Mullard M8137 , the military grade ECC83 equivalent. SInce it was supposed to be a sought after ECC83 of course a lot fo those listed on ebay will be fake but what would be the tell tell signs?


----------



## 340519

A fabulous match.


----------



## theBlackKey

I just got the icon hp8 mkii without copper plate variant and of course with out loop out circuit. My first impression is, it is extremely well built, it is clear, weighty sound and I love it so far. I will spend more time listen to it before I make a decision whether I should upgrade the capacitors or not.


----------



## 340519

I'm loving mine!


----------



## theBlackKey

Well I love every second with Icon Audio HP8 mkii, that being said, I am looking for an upgrade now. First my plan is to change the Ecc82 tube. I am thinking the Amperex bugle boy Holland made 12au7(ecc82). I will try that first and maybe in the future I will do the capacitors upgrade and I am thinking between Mundorf supreme silver gold oil and Jantzen Silver Gold. Have anyone tried these? I am happy with Shuguang treasure for now but could look for Psvane cv181 in the future.


----------



## RobertSM

Congrats on the new amp! As you already know the Icon Audio HP8 MKII responds very well to tube rolling and to a better capacitors upgrade. I had the Mundorf supreme silver oil installed. I was also thinking about the silver gold oil but thought I'd save a little money. I think both are excellent. In terms of input tubes, the Mazda from France, Telefunken from Germany and the Dutch bugle boy are all very good. For the 6SN7 tubes I really like the American NOS, Ken-Rad, Tung -Sol being my favorites.


----------



## theBlackKey

Hi Robert, thanks for your kind word. I will consider your suggestion. I just open up the back of the amp, it already upgraded with Jensen copper foil but I believe better capacitors and material will make it even better. I still have not decided what path I should go because I just got it today and really enjoy it as now. I manage to find the Amperex bugle boy for a good price so that would be my first upgrade to replace the electro hamornix ecc82.


----------



## Nik74

theBlackKey said:


> Well I love every second with Icon Audio HP8 mkii, that being said, I am looking for an upgrade now. First my plan is to change the Ecc82 tube. I am thinking the Amperex bugle boy Holland made 12au7(ecc82). I will try that first and maybe in the future I will do the capacitors upgrade and I am thinking between Mundorf supreme silver gold oil and Jantzen Silver Gold. Have anyone tried these? I am happy with Shuguang treasure for now but could look for Psvane cv181 in the future.



Just thought I d mention that a year ago I had emailed Icon Audio regarding options for replacement of the driver tube and they were not in favour of using an ECC82 in place of the ECC83 as it draws more current or heat-  it's not electrically the same. I too had used one for a week before checking with them -a Gold Lion 12AU7-, it sounded so pristine but clearly was making the amp and the 6SN7 s overheat...

Many great options to play with with ECC83 so why take a risk?


----------



## theBlackKey

Thanks Nik. Do you have any recommendation on what ecc83 tubes to look for?


----------



## Nik74

theBlackKey said:


> Thanks Nik. Do you have any recommendation on what ecc83 tubes to look for?


Of course but recommendations are very much based on personal taste 
Very decent: Gold Lion
Very lively and accurate/resolving: Tungsram
Incredibly insightful and detailed: Telefunken
goosebump inducing midrange magic  and musically haunting: Mullard MC1


----------



## 340519

I really like the gold lion tubes. They are definitely my favorite.


----------



## theBlackKey

Update:

I just receive the Telefunken Ecc83 West Germany. First impression is "WOW!" the mid range is like a steak well seasoned and cook to perfection. Musical and spacious. As @Nik74  recommend, I look forward to Mullard MC1 which is very rare and expensive Ecc83(12ax7). Maybe I will listen to it for a month before making a decision to upgrade the capacitors.


----------



## Nik74

@theBlackKey , your new valves will shine so much more efficiently with the new capacitors, those have to be replaced sooner rather than later .
Glad you re enjoying


----------



## theBlackKey

Yes, I think so, the capacitors right now is already Jensen updated by Icon Audio, but I feel it could have been much better with Mundorf silver gold oil or Jantzen silver gold, I have the experience with Mundorf silver gold oil myself, the capacitors actually bring details and clarity.


----------



## Nik74

My bad, I didn’t know you had the Jensens. You are good as you are I think !


----------



## rodrigaj

Would some one be so kind as to photograph the location of the capacitors that are being upgraded? Also, Jensen capacitor values and their specifications? If this has already been discussed just point me in the right direction. I would really appreciate that.


----------



## theBlackKey

I opened mine a couple of days a go but forgot to take a picture of it. I will try to do it tomorrow. In the meantime, I can tell you the value of two capacitors, it is 0.33uf.


----------



## 340519

I just bought a benchmark dac3 and through the hp8 to the 800S is just pure magic. Wow, does it sound good. The 800S has never had such dynamics.


----------



## theBlackKey

Congrats mate.


----------



## theBlackKey

@Nik74  How would you compare your current amp Luxman SQ-N 100 to the Icon audio hp8 mkii. I would love to listen to your opinion.


----------



## Nik74

theBlackKey said:


> @Nik74  How would you compare your current amp Luxman SQ-N 100 to the Icon audio hp8 mkii. I would love to listen to your opinion.



They are both great amplifiers but to my ears the Luxman is a significant step up in transparency, layering and detail retrieval.  Both are musically involving with the luxman having faultless PRAT while the icon is generally more laid back. 
I tend to listen to the Luxman more these days also because it is primarily a speaker amp and in that way more versatile. 
An area where the Icon seems to have the upper hand is the size of the soundstage which especially in terms of height and depth can be almost overwhelming, whilst the other one is a little more contained. 
Maybe I should do a direct comparison at some point for more detailed impressions. 
Right now if I had to choose one it would be the Luxman, but as it is I m happy I have both.


----------



## theBlackKey

Wel friends, I recently was fortunate enough to grab a good matched pair of PSVane cv181 II, I just spend few hours with it and so far, compared to the Shuguang Treasure, The Psvance has a touch more details. Most noticeably is the bass regions, treble is also a bit more details but still remains smooth. It seems that the Psvane make the holographic effect stronger and layering of instruments are very nice as welll. I also purchase the Psvane 12ax7 ii but I think personally I prefer the Telefunken more. Maybe, the tube needs burn in time to reach its full potential. I will report back my full experience before upgrading the capacitors to Mundorf.


----------



## RobertSM

theBlackKey said:


> Wel friends, I recently was fortunate enough to grab a good matched pair of PSVane cv181 II, I just spend few hours with it and so far, compared to the Shuguang Treasure, The Psvance has a touch more details. Most noticeably is the bass regions, treble is also a bit more details but still remains smooth. It seems that the Psvane make the holographic effect stronger and layering of instruments are very nice as welll. I also purchase the Psvane 12ax7 ii but I think personally I prefer the Telefunken more. Maybe, the tube needs burn in time to reach its full potential. I will report back my full experience before upgrading the capacitors to Mundorf.




Looks great! I noticed your telefunken tube looks to be the triple-mica type. These are thought to be the best that telefunken produced.  I also like your thinking in living with your system and the current configuration before you do the caps upgrade. This will allow you to learn and get to know the sound as it is. I think if you lump too many upgrades together it becomes harder to understand how your system responds to changes. It's also fun to have a few things in mind saving for the future.  

Either way, thanks for sharing. Keep us posted on tweaks and future upgrades. Cheers!


----------



## 340519




----------



## 340519

Above is an updated shot with my new gear.


----------



## theBlackKey

Love your setup mate.


----------



## 340519

theBlackKey said:


> Love your setup mate.


Thanks bud.


----------



## theBlackKey

After 50 hours of listening and tube rolling between Shuguang Treasure 50 years anniversary 6sn7 and Psvane CV181 Tii, I come to conclusion that I will stick with Shuguang 6sn7 and Psvane 12AX7, the reason for it is Psvane though are superior in terms of clarity, details, and soundstage, I find the soundstage are too huge for me. I makes my listening section less enjoyable and after 3 days listening to it when I switched back to Shuguang 6sn7 the music sounds more engaging and natural. As I believe audio is very subjective, you spend a lot of money for it and still it does not mean you will be happy with it. For me the next step is in the next two weeks I will order the Mundorf silver gold oil and prepare to rolling these capacitors in exchange with the current Jensen copper foil. I will report the whole process of upgrading these caps. Have a great day and great listening section.


----------



## 340519

I've moved the icon to my bed room setup and use it strictly with the lcd x and xc. Really still enjoying the amp and it sounds spectacular with the audeze cans.


----------



## RobertSM

I'm glad you're enjoying you Icon!

I've recently also changed my headphone listening system up. With everything stay-at-home now I've really had some great time to really enjoy it too. I've changed the tubes around and have been very happy with a great combination of NOS tube set. Really a lovely amp!


----------



## 340519

I had just emailed icon about the audeze's pairing with the icon and got a nice response:

There should be no reason why your Audeze headphones should not work fine with the HP8 MkII. We have had customers with these types of headphones and not reported any problems. At 20 Ohms you would normally use the low impedance setting on the HP8 MkII (for 8-32 Ohms) setting. 

Regards

Icon Audio (UK) Ltd
351 Aylestone Road
Leicester LE2 8TA U.K.
(+44) 0116 2440593
(+44) 07787 158791
Email: sales@iconaudio.com
www.iconaudio.com


----------



## theBlackKey

Well friends, I can tell from my own experience that Icon Audio HP8 mkii works great with planar magnetic headphones, I am now pairing it with my Abyss Diana and Hifiman Edition X v2 on medium output impedance and notice no distortion in sound. Also, I try to experiment switching from low output to medium and high to see if there is differences. And there are, in fact on low output my edition sound pretty goods with clarity and dynamic but a bit lack in body, I should say as refined sound. While switching to medium I notice substantial change in volume and body, basically it still maintains dynamic and clarity but you get more body to the mid range. What can I say, Icon Audio HP8 mkii in fact is versatile amp and one of the best amp I own. Also, I changed the power cord to audiophile grade and also notice an improvement in overall quality. I guess cables are still a debatable subject and in fact very subjective matter, however, I am speaking based on my own experience and I cannot deny the fact the power cord did improve my Icon Audio Hp8 mkii quietly substantial.


----------



## 340519

Maybe I'll experiment with the gain settings tonight. I have kept it in the low setting with the x and xc.


----------



## RobertSM

I agree. I also upgraded to a Hi-Fi level power cord and noticed a good improvement. The Icon Audio HP8 MKII had a more quite and dark background. I also noticed what I believe to be faster transients. Also more deep and refined bass. These of course are my experiences using Audioquest NRG-Y3. Either way, I think a few small tweaks can go along way to really let the Icon shine.


----------



## 340519 (Apr 30, 2020)

Would you all recommend a higher gain on the Icon with the Audeze even if they are 20 ohm?

Edit: It seems the medium gain brings out more dynamics in the x and xc, but high seems to just become too much


----------



## Jay Smith

My 12AX7 electro-harmonix is not working, I just find the top silver coating is gone, is it a common issue to tube?  It was only one year old and I did not use it often.


----------



## theBlackKey

Very rare, I have not seen the coating wear out like that. Do you have replacement tube?


----------



## RobertSM

Maybe the heat vaporized the silvering of the tube? I too haven't seen this before.


----------



## 340519

RobertSM said:


> Maybe the heat vaporized the silvering of the tube? I too haven't seen this before.


I haven't either.


----------



## Jay Smith

Perhaps just my bad luck, my other 12AX7 are just fine.


----------



## 340519

Jay Smith said:


> Perhaps just my bad luck, my other 12AX7 are just fine.


I really like the gold lion in my hp8,  but I just got the tubestore.com house brand 12AX7 and it's supposed to be more warm and gooey which is what I'm seeking.


----------



## Jay Smith

This is my HP8mk2, the layout is quite different to others I google, normal? 

If I want to upgrade capacitors, is the spec 630V, 0.33uF correct?  Thanks.


----------



## roskodan

Jay Smith said:


> My 12AX7 electro-harmonix is not working, I just find the top silver coating is gone, is it a common issue to tube?  It was only one year old and I did not use it often.



That is the metallic deposit from the getter. If it's gone, it means the vacuum inside the tube has been compromised. The tube is dead.


----------



## roskodan

Jay Smith said:


> This is my HP8mk2, the layout is quite different to others I google, normal? If I want to upgrade capacitors, is the spec 630V, 0.33uF correct?  Thanks.



I use these in my HP8 mk2


----------



## Jay Smith

roskodan said:


> I use these in my HP8 mk2


Thanks!


----------



## Jay Smith

roskodan said:


> That is the metallic deposit from the getter. If it's gone, it means the vacuum inside the tube has been compromised. The tube is dead.


I have no idea what caused the leakage, The tube was stored and seldom used.


----------



## 340519

I just read that the hp8 is a repurposed ming da amp made in china. Hmmmm interesting...


----------



## roskodan

Nowadays every amp is a "repurposed" amp. The original HP8 and MP3 look like Ming Da clones.


Spoiler: MC84 EAR


----------



## 340519

Man, one of the electo harmonix gold tubes has already gone bad. I've only run them for a few months and then one of them developed the dreaded static squealing.  It sounds like a demonic character whispering to me through the damned things. Well the psvane standbys are working fine.


----------



## Jay Smith

Mmmh, perhaps we should stay away from electro harmonix.......


----------



## 340519

Jay Smith said:


> Mmmh, perhaps we should stay away from electro harmonix.......


I bought the matched pair from thetubestore.com.  I'm going to try the northern lights tubes next I think.


----------



## Nik74

I gave up on the  Tubestore very early on. On my first order they sent the wrong 12AX7 which at least was in working order. When I emailed them to let them know they admittedly sent me a replacement free of charge but the replacement was humming so intensely that it was unusable. 
I ve had more luck from eBay so far- quite unbelievably!-


----------



## 340519

Nik74 said:


> I gave up on the  Tubestore very early on. On my first order they sent the wrong 12AX7 which at least was in working order. When I emailed them to let them know they admittedly sent me a replacement free of charge but the replacement was humming so intensely that it was unusable.
> I ve had more luck from eBay so far- quite unbelievably!-


Wow okay. I might try ebay next.

The David Shaw tubes that came with it sound good and are quiet. I'm using them and the gold lion for now.


----------



## 340519

I'm going to stick with the gold lion 12AX7,  but what would you all recommend for the 6sn7 slots? Something warm and gooey that I could find on ebay or canuck audio mart. Thanks guys.


----------



## Nik74

6SN7 are not as readily available here in the UK as they are in the states so take this from someone who hasn’t tried several of the great ones but my favourites with the Icon have been a pair of CBS Hytron- dirty cheap on eBay. Such an expansive sound space and 3D sense with the HD800S...


----------



## Nik74

dmdm said:


> I'm going to stick with the gold lion 12AX7,  but what would you all recommend for the 6sn7 slots? Something warm and gooey that I could find on ebay or canuck audio mart. Thanks guys.



if you want warm and gooey get your hands on a Mullard ECC83 in place of your Gold Lion, much more of an effect on overall sound plus the most magic midrange!


----------



## 340519

Nik74 said:


> if you want warm and gooey get your hands on a Mullard ECC83 in place of your Gold Lion, much more of an effect on overall sound plus the most magic midrange!


I have a new one of those from thetubestore,  or are you referring to nos?


----------



## 340519

Nik74 said:


> 6SN7 are not as readily available here in the UK as they are in the states so take this from someone who hasn’t tried several of the great ones but my favourites with the Icon have been a pair of CBS Hytron- dirty cheap on eBay. Such an expansive sound space and 3D sense with the HD800S...


Thanks, I have saved a CBS hytron search on ebay.


----------



## Nik74

dmdm said:


> I have a new one of those from thetubestore,  or are you referring to nos?



most definitely Nos


----------



## 340519

Nik74 said:


> most definitely Nos


Ah darn it.


----------



## 340519

I guess I'm sticking with the gold lion for now. I also have a new mullard, a tube store house brand 12AX7,  and the original that came with the hp8.


----------



## 340519 (May 10, 2020)

So the noise doesn't seem to be coming from the tubes at all, as the sound made a comeback with the replacements. It appears that it's dirty power created by an led light on the same circuit. We shall see.


----------



## Jay Smith

dmdm said:


> So the noise doesn't seem to be coming from the tubes at all, as the sound made a comeback with the replacements. It appears that it's dirty power created by an led light on the same circuit. We shall see.


My HP8mk2 always picking up noise from a pair of TP-Link AV1000 Powerline ethernet adapters............


----------



## 340519 (May 10, 2020)

Well there is random static, and almost digital ticks that are random on one channel (the digital pops are new), so I'm thinking all this is might be caused by some sort of interference/noise in the house power. Now as I write this the noises are gone, so I don't think it's the amp or tubes.


----------



## 340519

Jay Smith said:


> My HP8mk2 always picking up noise from a pair of TP-Link AV1000 Powerline ethernet adapters............


What sort of noises?


----------



## Nik74

I have experienced this too with the Icon and judging by how much more it happens during the day as opposed to very late at night, I d say too that it is related to power quality. However the noise of a defective tube is not that dissimilar so it can be confusing to figure out what’s what. The Luxman I use at the moment is equally sensitive but shows different symptoms. 
Could this be a tube thing? I lack the technical knowledge to support this thought but perhaps tubes pick RF and other noise like antennae and at certain frequencies they translate it into audible noise ? 
It would be interesting to hear from someone who understands and can explain the technicalities of the science behind this.


----------



## Jay Smith

dmdm said:


> Well there is random static, and almost digital ticks that are random on one channel (the digital pops are new), so I'm thinking all this is might be caused by some sort of interference/noise in the house power. Now as I write this the noises are gone, so I don't think it's the amp or tubes.


Hiss at low level, the only way to get rid of it is unplugged TP link...


----------



## 340519

Nik74 said:


> I have experienced this too with the Icon and judging by how much more it happens during the day as opposed to very late at night, I d say too that it is related to power quality. However the noise of a defective tube is not that dissimilar so it can be confusing to figure out what’s what. The Luxman I use at the moment is equally sensitive but shows different symptoms.
> Could this be a tube thing? I lack the technical knowledge to support this thought but perhaps tubes pick RF and other noise like antennae and at certain frequencies they translate it into audible noise ?
> It would be interesting to hear from someone who understands and can explain the technicalities of the science behind this.


Thanks fellas. When thinks go wrong with my equipment it has the tendency to make me a little nutty.


----------



## SteveM324

I had issues a few years ago with noise from WiFi boosters/ethernet extenders that I was using for streaming.  I got rid of the noise by using a long ethernet cable and moving the booster away from my tube preamp/headphone amp.  I think physically distancing (as opposed to social distancing) helps to eliminate the noise.  If the extender is a wall mounted device, plug it into an outlet further away from your amp and use a longer ethernet cable.


----------



## 340519 (May 14, 2020)

Hi guys, I just bought some zebra wood audeze lcs 4s which I am very excited about! They are 200ohm. On the high gain setting the icon is advertised to drive cans up to 600ohms, so I'm thinking the amp will power them okay? Thoughts?


----------



## RobertSM

dmdm said:


> Hi guys, I just bought some zebra wood audeze lcs 4s which I am very excited about! They are 200ohm. On the high gain setting the icon is advertised to drive cans up to 600ohms, so I'm thinking the amp will power them okay?



No problem at all! They drive my Sennheiser HD650's with ease.  

Enjoy!


----------



## 340519

RobertSM said:


> No problem at all! They drive my Sennheiser HD650's with ease.
> 
> Enjoy!


Thank you sir!


----------



## RobertSM

And those HD650's are 300 ohm.

So your 200 ohm cans should be just fine.


----------



## henkeman

hood177 said:


> Hi* RobertSM*,
> thank you for rating.
> I have already modified it twice.
> 1. Upper plate - anodized aluminum. Original plate - anodized aluminum too, not copper.
> ...


Nice Mod! How do you think Psvane Treasure 12AX7 LS Special Edition compares to the best of your NOS 12AX7 tubes? I have it my self and wondering if it's worth pursuing the NOS tubes.


----------



## Steve160k

Has anyone had a comparison with the Icon HP 205D headphone amp? The 205D is a big step up in cost at three times the price, and also has a separate power supply, so looks a serious bit of kit. I am looking at valve amplifcation after using a Chord Hugo 2 for the last yearr or two. The Hugo 2 is very transparant, but maybe a little too clinical and lacks a bit of soul.


----------



## The Jester

Got the latest one of these coming in the next week or so ...
HP8 with factory cap upgrade and upgraded valves ...
More when it gets here and a bit of running in ... 🙂


----------



## Coztomba

The Jester said:


> Got the latest one of these coming in the next week or so ...
> HP8 with factory cap upgrade and upgraded valves ...
> More when it gets here and a bit of running in ... 🙂



Excellent stuff.  What headphones will you be using with it?  Are you purchasing brand new?


----------



## The Jester (Dec 6, 2020)

Yup, brand new from local dealer .. long trip from the UK though..
Headphones are Quad ERA-1 and multi use Sennheiser HD630VB..


----------



## Coztomba

The Jester said:


> Yup, brand new from local dealer .. long trip from the UK though..
> Headphones are Quad ERA-1 and multi use Sennheiser HD630VB..



I also bought mine new last year from Decibel Hifi in Aus and haven't regretted it.  Particularly good with the Focal Clear and Grado Hemp's.  Looking forward to your impressions!


----------



## The Jester (Dec 6, 2020)

Coztomba said:


> I also bought mine new last year from Decibel Hifi in Aus and haven't regretted it.  Particularly good with the Focal Clear and Grado Hemp's.  Looking forward to your impressions!


Luckily I’m only a 15 minute drive from them .. 😃
will be driven from a Chord Qutest/ MScaler or Rega P6 / Reflex M


----------



## The Jester

Just picked it up today,
Manual states upgraded caps are now Mundorf silver gold ... nice ...
just need to install it and get it warmed up ...


----------



## The Jester

Only an hour here and there so far, 
12AX7 Is an EH gold which I don’t mind, tried both those and Gold Lion 6992’s in my CJ preamp and slightly preferred the EH ...
2021 here already so Happy New Year and a quick photo ....


----------



## The Jester (Jan 7, 2021)

Been running for a few days now and opened up a little more, using Quad ERA-1 seems a nice match, the previous amp was an Eximus DP1 and the major improvement is soundstage and detail, not in an analytical way but as the soundstage opens in width but mainly depth it reveals almost hidden levels of low level detail, instrument texture and timbre improved from bass upwards and a nice sparkle to cymbals in the high end without being harsh or “tizzy” , a really “analogue” sound for want of a better description,
Next will be an extended listen to some vinyl and see if there’s a similar improvement or if the gap has closed even further ....
I’ll be happy either way ... 🙂
Update:
after a few vinyl albums I think the gap may have closed a little, still a nice improvement with vinyl replay but maybe via digital that last little hint of digital hardness seemed to gone ....


----------



## MLGrado

Well, my second ICON HP8 MKII has died with virtually no customer service from Music Direct. 

First one the 12AX7 socket broke.  I bought it second hand so no warranty.  I understood and moved on. 

Second unit was new from Music Direct with full warranty.  Still under the two year warranty, and yesterday I woke up, and turned on dead amp. 

Yes, changed fuses.  Changed tubes, Changed power cord, Changed power strip, tired different outlet.  NADA.  Dead amp.  No sound, no red light, no tube power.  no heater etc. 

SO I called MD.  They said I had to call Icon in Britain.  

GREAT.  MY product purchased from authorized dealer, wont fix it here in the states.  Has to go back to Britain, which is helluva expensive shipping on my part, in middle of a pandemic that means it will take months probably.  Even then, China may come into play for parts and service according to Music Direct. 

Anyone have experience with Icon support????  This far I am NOT impressed.


----------



## shabta

MLGrado said:


> Well, my second ICON HP8 MKII has died with virtually no customer service from Music Direct.
> 
> First one the 12AX7 socket broke.  I bought it second hand so no warranty.  I understood and moved on.
> 
> ...


That's pretty horrible that Music Direct isn't helping facilitate. I have had dealing with the icon audio people, they respond promptly to emails. There's a good chance David Shaw will personally get involved. I have had my icon for 6 or 7 years w/o problems. I did send it to the UK (pre brexit) to upgrade the caps. I live in france so that was much smoother. Best of luck.


----------



## -Darkstar-

MLGrado said:


> Well, my second ICON HP8 MKII has died with virtually no customer service from Music Direct.
> 
> First one the 12AX7 socket broke.  I bought it second hand so no warranty.  I understood and moved on.
> 
> ...


Sorry to hear this. I bought mine from MD, also. Luckily I haven't had any problems.


----------



## The Jester

MLGrado said:


> Well, my second ICON HP8 MKII has died with virtually no customer service from Music Direct.
> 
> First one the 12AX7 socket broke.  I bought it second hand so no warranty.  I understood and moved on.
> 
> ...


Any update on the Icon Audio warranty support ?


----------



## JonT (Aug 8, 2021)

It's been fascinating to chronologically read the 41 pages of this thread - across different iterations of the HP8 - with all the distilled experience regarding headphone pairings, capacitor and valve upgrades, and so on.

My HP8 Mk2.2 SE arrived yesterday (Mundorf Silver Gold capacitors; Treasure CV181+; EH GP 12AX7) and I've listened for 5 hours.

My set-up is an all analogue system with HD800S.

In recent months I have had at home: Graham Slee Solo ULDE, Pathos Aurium, IFI Pro iCAN, SPL Phonitor 2.

I arrive at the HP8 following a recent phono stage change (from Graham Slee Accession to Cyrus Phono Signature). The Cyrus was a major improvement - particularly noise floor, detail, and imaging - and while bass articulation was also greatly improved, the overall low end heft was reduced. With HD800S into the Phonitor 2 this trade off was problematic on problematic recordings.

I rather enjoyed the Pathos Aurium which I had in my system last autumn.

(In fact, I had two units and both sadly were defective. On the first, the power inlet separated off the PCB; the second had a major heat problem somewhere, and collapsed into distortion after running for an hour. The UK Pathos distributor can most charitably be described as eccentric.)

In my system, there was good synergy with the HD800S.

The IFI Pro iCAN is something I hope never to listen to again.

The SPL Phonitor 2 I enjoyed for around six-months when the Graham Slee Accession was still in the chain. Excellent detail and dynamic authority. Well-mastered recordings sounded superb. I did a good deal of experimentation with the crossfeed and laterality controls, and found that they invariably made music sound worse.

For now, the Phonitor 2 is side-by-side with the HP8 and so I have been able to A/B.

Certainly, the HP8 restores the body and texture which had atrophied in the Cyrus-Phonitor-HD800S chain. As others have reported, the HP8 does have an impressive way of adding richness without sacrificing detail. At this early stage, what I do miss about the Phonitor are its huge and authoritative dynamic contrasts. Perhaps SPL's 120-volt technology is more than just a gimmick (as suggested by some). On both listening sessions (yesterday and today) I found the HP8 took around an hour before it really sang.

Briefly experimented with interactions between the Cyrus (settings for gain and resistance) and the Impedance setting on the HP8. Initial findings seem to echo what others have observed about the thickening effect on tone when switching from 'M' to 'H' with HD800S. At this early stage, overall I have found the 'H' setting is the most pleasing, and perhaps does make sense given that although nominally 300-ohms the HD800S present 600-ohms at lower frequencies.

Channel matching seems excellent.

Build quality seems excellent. I've no problem with the business model of Chinese manufacturing and UK finishing, tuning, and quality control.

I guess like everyone else I now need to consider whether to further upgrade the valves (especially the input?) - holding in mind the tonal the particularities of the rest of the chain.

Finally, I've found the noise floor of the HP8 to be very good. There is a slight transformer hum not audible above the noise floor of vinyl even between songs.

Again, many thanks to everyone who contributed to this thread across many years and 41 pages!


----------



## The Jester

Still more than happy with mine too, so far resisted any urge to try different valves as the HP8/ Quad ERA-1 is still my go to pairing for anything more than occasional listening, 
There seems to be too much made about sourcing from China and that could stem more from the customer than the supplier, I attended an Automotive trade show a few years ago that had extensive Asian exhibitors and chatting with one of their engineers made it obvious to me, if I said I wanted xx part for $10 in lots of 1,000 I’d have several options, but I could also ask for something to match a detailed spec sheet including any certification I wanted it to pass and be quoted a price on various amounts,
There‘s also the lifespan of average consumer electronics too, How many of us have replaced say a TV because it failed or the picture quality degraded ? …. Something that you want to last longer ?, I recently bought a computer PSU with a 12 year warranty 😃


----------



## MLGrado (Aug 25, 2021)

I am on my THIRD Icon Audio HP8 MKII. 

First was used, purchased here on HeadFi used for a good price.  Sounded really good.  I ended up over-doing the tube roll and broke a socket.  I still have this amp plus replacement sockets for replacement on a rainy day. 

Before I repaired that one, I saw MD had a display model for sale at a great price, with full warranty.  Sounded even better than the original model I first bought.  Its power supply died, luckily for me less than two months before warranty expired. 

Finally, 6 months later I got a brand new in box replacement.  Never bothered to open the stock tubes.  I went straight to 1959 Valvo ECC83 Short Plate I60 code, and using adapters I have a pair of true never opened NOS RCA 6F8G from 1940's. Lucky for me, I also have a second pair never opened, still sealed in its cardboard/tin metal box. 

I don't really 'believe' in warm up, but this experience has made me a true believer especially amps with bespoke parts, and brand new headphones with little hours on them. 

Really unimpressed at first, no matter what headphone.  It sounded fine, but I was still preferring the balanced output (pentaconn) on my Ifi IDSD Pro DAC/Amp.  Then after a few weeks, something changed.  Please be as skeptical as you like, but suddenly this amp 'opened' up and started pushing out astonishingly good sound.  Powerful yet nuanced, with excellent tone.  Midrange to die for, smooth treble, Tight bass, but that is to be taken in the context of 'tube bass'. 

Then things REALLY kicked up a notch.

I had purchased a FOCAL Clear MG PRO and it arrived at the exact same time as the ICON amp.  Similar story.  The phones never sounded even close to a $1.5k headphone.  Regardless of amp.  But I paid a $hit load for me amount of money, so I was going to give them a chance.  The sound got better and better. Dynamics and contrasts became more readily apparent, soundstage grew, tone became almost spot on.

Bottom line, between the two I was hearing the very best headphone audio I had every heard since I started this hobby, and I have been through a LOT of stuff in the price range and more (in some cases unfortunately). 

I was a previous owner of the FOCAL Clear Pro and used it for hundreds and hundreds of hours with my 'second' HP8 MKII.

I can tell you this without a doubt.  That combo really never ever came close to this one.  We know the Focal Clear MG is a performance upgrade, but it wasn't an 'OH MY GOD' Moment on my RME ADI-2 PRO _FS R._

Which leads me to think the 'OH MY GOD' moment may have something to do with continual improvements with the ICON AUDIO HP8 MKII.  This latest version I can honestly say (subjective of course, but I feel SO strong about this) is a major performance boost from the MKII of several years ago.


My reference system is now Audirvana running on Mac Mini with LPS and fan upgrade feeding a iFi iDSD PRO DAC (software 2.08) galvanically isolated from from the MAC with an Intona Isolator.  iDSD feeds ICON AUDIO HP8 MKIl, listening via FOCAL Clear MG PRO headphones. 

*To date, this is THE BEST SYSTEM I HAVE EVER HEARD for headphones.   At this time, my upgraditis is cured.  (For the moment I say lol)  

Its sounds so good, I am debating taking the tiny risk involved in a super easy job replacing the coupling caps with the factory recommended Jensen upgrade.




Today I am cleaning, 'restyling', and re-wiring the system in anticipation of new racks.*





*THE BEST SOUNDING ECC83 I have EVER heard in the Icon, and that includes the older LONG plate Valvo and Amperex with large foil getter as well.  Short gray plate I60 code a KILLER sound










To JENSEN or NOT to JENSEN the output caps, that is the question?!!



*


----------



## The Jester

From other users here the cap upgrade is noticeable too, mine is around 8 months old straight from the factory and came with the latest Mundorf  caps, don’t know if that was a further minor upgrade or just a supply issue, I ordered it at the same time I bought the Quad ERA-1 and they were well and truely “run in” by the time the amp arrived, sounded ok straight up but as you say after running on a loop overnight a few times it just “opened up”, still using the supplied “se” valves at the moment and driven from a Chord MScaler/Qutest the sound is way better that I ever expected, no real desire yet to start “tube rolling” and any possible further improvements can wait for now …


----------



## MLGrado (Aug 26, 2021)

The Jester said:


> From other users here the cap upgrade is noticeable too, mine is around 8 months old straight from the factory and came with the latest Mundorf  caps, don’t know if that was a further minor upgrade or just a supply issue, I ordered it at the same time I bought the Quad ERA-1 and they were well and truely “run in” by the time the amp arrived, sounded ok straight up but as you say after running on a loop overnight a few times it just “opened up”, still using the supplied “se” valves at the moment and driven from a Chord MScaler/Qutest the sound is way better that I ever expected, no real desire yet to start “tube rolling” and any possible further improvements can wait for now …



In time I will check and see what caps are in the current model.  Mine came from the very latest shipment from Icon to the USA.  Music Direct is our only dealer here so they come in large batches all at once, therefore they can be out of stock for quite some time of any given model.

Having heard the original Focal Clear Pro, Audeze LCD-2 and LCD-X, Hifiman HE560, Sennheiser 650's, Mr Speakers Ether Flow, (so all what I would consider excellent fidelity before taking that very next step off the cliff to things like LCD-4, Utopia, Abyss, etc,) I can say with little doubt this HP8 MKII 'bloomed' into another level of performance compared to my previous two.

Quite astonishing.  I wish I could get more ears on my system.  It is astonishingly good.  Well, it should be for the total price, but, as well all too well know that often isn't the case.


----------



## Coztomba

Grant Fidelity Treasure Glove 6SN7-SE's with a Sophia Electric 12AX7.  Crappy 3 year old phone pic.  I need to take some better shots with a DSLR.


----------



## WorksUnit

Well the recap sounds like a way forward.
How do I safely open one of these to check what caps are in mine?


----------



## The Jester

WorksUnit said:


> Well the recap sounds like a way forward.
> How do I safely open one of these to check what caps are in mine?


Pretty sure if you go back through the pages in this thread there‘s photo’s and Cap info around … 🙂


----------



## WorksUnit

Cheers. Been reading this thread, but seems like a lot of experienced people working on electronics commenting.
I`m not one of them, just don`t want to do anything silly.


----------



## The Jester

Page 31 has a photo of the insides ..
Dont go inside until you read up on discharging the caps, transformers etc though …
Dangerous voltages inside even when turned off and unplugged … 😳


----------



## The Jester

Play it safe, buy the recommended caps and have a tech install them for you, 
fairly easy so shouldn’t cost too much …


----------



## jonathan c

Coztomba said:


> Grant Fidelity Treasure Glove 6SN7-SE's with a Sophia Electric 12AX7.  Crappy 3 year old phone pic.  I need to take some better shots with a DSLR.


I bet that if your phone were tube-driven it would take better pictures! 😜😆…


----------



## WorksUnit

Recap booked with Icon....Mundorf MCap EVO silver gold oil.
Should be away for a couple of weeks, really feel like I`m going to miss it though.


----------



## MLGrado

WorksUnit said:


> Cheers. Been reading this thread, but seems like a lot of experienced people working on electronics commenting.
> I`m not one of them, just don`t want to do anything silly.


the recap is extremely easy to do on this unit.  Well, the output coupling caps anyway.   I am not a novice at this, but certainly no expert.  I am currently replacing a broken tube socket (the 9 pin input) on one of my two HP8.  THAT is a difficult job for me.  It requires great care, with lots and of parts to work around.  

Comparatively the cap switch is as easy as a manual can-opener.  

I have Jensen upgrades right here waiting. 

My only concern is their rating does NOT match what is on the stock caps.  

BUT the Jensen cap and the ratings to use came DIRECT from the horse's mouth at Icon.  On the phone they insisted the Jensen caps should match the spec they quoted and not to pay attention to the other brand's specs.  

I have seen where people have gone either direction with this.  As quoted by Icon, or using an upgrade cap that matches specifications on original caps.  

So, that is really why I am at an impasse on the cap upgrade.  The upgrade itself is SUPER SUPER easy to do.


----------



## MLGrado

Coztomba said:


> Grant Fidelity Treasure Glove 6SN7-SE's with a Sophia Electric 12AX7.  Crappy 3 year old phone pic.  I need to take some better shots with a DSLR.


Not a new production tube guy myself.. I have a collection of hundreds (once was thousands until I decided to liquidate most on eBay) NOS and lightly used vintage tubes.  

But these are BEAUTIFUL 6SN7 tubes.  I am going to order a pair and see how they compare to the RCA 6F8G New Old Stock from WWII era I am currently in love with.


----------



## JonT (Oct 23, 2021)

Although I've only had my HP8 Mk.2.2 SE since August - approx 45 hours playing time - one of the supplied SE output tubes (Treasure CV181) seems to have gone noisy.

[On powering up the unit, with the volume completely down and without the source playing, a loud rustling sound in the right ear-cup of the HD800S... after a few minutes it calms down, but a barely perceptible intermittent crackle continues]

In fairness, both Icon Audio and the retailer, Audio Affair, requested I send the tube back "for testing"... but rather than immediately going down the track of replacing the supplied tube with perhaps a less-than-ideally matched replacement, I may begin experimenting with some tube rolling.

I use the HP8 with a turntable source only (Technics SL1200G - Benz Micro Glider SL approx. 350 hours - Cyrus Phono Signature) into Senn HD800S.

Based on the 45 hours I have listened thus far, I feel I could benefit from a smidgen less warmth, slightly faster dynamics, a little extra detail. This without altering the character of the HP8 too much, which tames the stridency of the HD800S perfectly.

The input tube is the supplied EH gold pin.

Any recommendations gratefully received...


----------



## MLGrado

JonT said:


> Although I've only had my HP8 Mk.2.2 SE since August - approx 45 hours playing time - one of the supplied SE output tubes (Treasure CV181) seems to have gone noisy.
> 
> [On powering up the unit, with the volume completely down and without the source playing, a loud rustling sound in the right ear-cup of the HD800S... after a few minutes it calms down, but a barely perceptible intermittent crackle continues]
> 
> ...




Sorry to go a different direction here, but I was not aware of the Mark2 , 2.1 and 2.2 designators

What are the differences, and how can you tell which is which?  All I know is this current one I am using has a build date earlier in 2021, but standard caps.  The two others I have owned were Mark 2, but looked identical externally.  I can say they went in chronological build order, and each sounded a bit better than the previous, or so it seemed.


----------



## JonT

MLGrado said:


> Sorry to go a different direction here, but I was not aware of the Mark2 , 2.1 and 2.2 designators
> 
> What are the differences, and how can you tell which is which?  All I know is this current one I am using has a build date earlier in 2021, but standard caps.  The two others I have owned were Mark 2, but looked identical externally.  I can say they went in chronological build order, and each sounded a bit better than the previous, or so it seemed.


The current model - with the copper top plate - is the third iteration of the HP8 that Icon Audio have produced, but it was never differentiated in name from the earlier Mk2. This has led some to coin the term Mk2.2 to describe the latest version.

Someone else may be able to confirm this, but I recall that there was no circuit design changes - only a casing update - from Mk2 to Mk2.2 and this might be why Icon Audio never changed the model designation.

And of course, since October 2021, Icon Audio are listing three instead of two options on the Mk2.2 - standard, with Bluetooth, Bluetooth SE (and a price hike)!


----------



## MLGrado

JonT said:


> The current model - with the copper top plate - is the third iteration of the HP8 that Icon Audio have produced, but it was never differentiated in name from the earlier Mk2. This has led some to coin the term Mk2.2 to describe the latest version.
> 
> Someone else may be able to confirm this, but I recall that there was no circuit design changes - only a casing update - from Mk2 to Mk2.2 and this might be why Icon Audio never changed the model designation.
> 
> And of course, since October 2021, Icon Audio are listing three instead of two options on the Mk2.2 - standard, with Bluetooth, Bluetooth SE (and a price hike)!




Then it would make more sense that the differences in sound I heard were likely from the first copper plate version being very well used when purchased; likewise the second was a floor demo model at Music Direct, so who knows how many hours were on it.  The third was brand new in box.   All of these factors plus indeed any production minor changes down the line could be why I heard such difference in sound.  ( I have barely ever used the stock tubes.  The David Shaw signature edition did sound okay though.  I still have them in box... Psavane CV181 did sound decent to me.)


----------



## geoffalter11

Hi all HP8 owners and thread goers... I am new to the world of the Icon HP8.  I just bought a Signature Edition with the Mundorf Caps and the Ceramic CV181's and Electro Lux Russian 12ax7.  First and foremost, I love this amp.  I am having so much fun with it.  It has finally made my Auteur sound like the amazing dynamic headphone I knew it could be.  It was good on my Mainline, and really good on my Cembalo Labs Spring 1.  But, on the HP8 it is something else entirely.  Love it!

So, few questions... I have not read through the whole thread yet, so I am sure these questions have already been asked and or discussed, but I thought I would ask anyhow.

1. How much does tube rolling affect the sound of the HP8?
2. Which CV181's or 6SN7 or Variants do you recommend with the HP8?  I have looked at the Ken-Rad, Hytron 5692 and a V231 NOS.  They are really expensive.  Are the Ceramic CV181 Shaw's the best 6SN7 for the HP8?
3. Which 12AX7 do you all like best with the HP8?
4.  Which of the two different tube types has most impact on the sound?
5. Do you feel the Mundorf Caps are the best caps for the HP8?

That's it for now... Thank you!


----------



## The Jester

Had the exact same edition since this time last year and haven’t been tempted to change a thing …. Yet ..😬
I’m sure there’s more than a few out there with results from tube rolling but for me going with the designers chosen SE tubes was a “safe bet”, and just about all manufacturers use freely available new construction vs NOS for consistency and continued availability, if mine continues to sound as it should I may consider rolling the 12AX7 as I have a preference for Gold Lion small signal tubes over EH in my preamp, but that can wait until they need replacing.


----------



## WorksUnit

@geoffalter11 thanks for sharing you experience with that ZMF


----------



## -Darkstar-

geoffalter11 said:


> Hi all HP8 owners and thread goers... I am new to the world of the Icon HP8.  I just bought a Signature Edition with the Mundorf Caps and the Ceramic CV181's and Electro Lux Russian 12ax7.  First and foremost, I love this amp.  I am having so much fun with it.  It has finally made my Auteur sound like the amazing dynamic headphone I knew it could be.  It was good on my Mainline, and really good on my Cembalo Labs Spring 1.  But, on the HP8 it is something else entirely.  Love it!
> 
> So, few questions... I have not read through the whole thread yet, so I am sure these questions have already been asked and or discussed, but I thought I would ask anyhow.
> 
> ...


I didn't get the Signature Edition so rolling in a Gold Lion 12AX7 and some EH Gold Pin 6SN7's, greatly improved treble extension and bass impact over the stock tubes.


----------



## geoffalter11

WorksUnit said:


> @geoffalter11 thanks for sharing you experience with that ZMF


Welcome


----------



## Jay Smith

Welcome, owning it for three years now, no issue, very reliable, great sound.


----------



## cpetrillo

Interesting thread, been watching the hp8 for a while now. My main amp is the Icon Stereo 40 mk4 and I love this amp. It actually has a very good headphone output using separate windings on the output transformer.


----------



## JonT

cpetrillo said:


> My main amp is the Icon Stereo 40 mk4 and I love this amp. It actually has a very good headphone output using separate windings on the output transformer.


I've always wondered about this!

Amazing to hear from someone who actually has the Stereo 40 Mk4!

My front-end is all vinyl (SL1200G, Benz Micro Glider SL, Cyrus Phono Signature) into a Rega Elex-R and ProAc DT8. That's 113 watts into the nominal 4 ohm load of my speakers. I appreciate that much of the time I'm barely pulling a few watts. I always wondered, with 40 watts, what happens when the speakers suddenly demand a lot of power (eg. big dynamic swings)?

I also have always wondered about the headphone output on the Stereo 40 versus the HP8. Again, I appreciate the HP8 is a different circuit design (class A, single ended), but in a blind and volume matched test, could I tell much of a difference, I wonder?


----------



## cpetrillo

Have never heard the hp8 so can’t comment on that. The st 40 is actually 50 watts in ultrlinear mode and I think 30 or 35 in triode mode. My Sonus faber speakers are not particularly efficient but have not had any problems. The headphone jack is rated for 8 to 600 ohms and sounds very good with my lcrx headphones.


----------



## jonathan c

cpetrillo said:


> Interesting thread, been watching the hp8 for a while now. My main amp is the Icon Stereo 40 mk4 and I love this amp. It actually has a very good headphone output using separate windings on the output transformer.


😜…’watching’ rather than ‘looking at’? What has hp8 been doing?…..Actually, if it were not for the tube h/p/a (OTC and OTL) that I have, I would be a hp8 buyer:  2 x 6SN7 and 1 x 12AX7 (great tube rolling territory), point-to-point wiring, beautiful copper plate…😋


----------



## geoffalter11

jonathan c said:


> 😜…’watching’ rather than ‘looking at’? What has hp8 been doing?…..Actually, if it were not for the tube h/p/a (OTC and OTL) that I have, I would be a hp8 buyer:  2 x 6SN7 and 1 x 12AX7 (great tube rolling territory), point-to-point wiring, beautiful copper plate…😋


It is an awesome amp. Loving it! Sounds is sweet, gentle and dynamic simultaneously.


----------



## Loftprojection

Hey folks, any of you HP8 owners have Meze Empyrean?  Wondering about synergy with those cans.

As well, any of you had a chance to compare the upgraded version against slightly more expensive tube amps like the Feliks Elise or Dragonfire IHA1, Ampandsound Kenzi, LTA MZ2...?


----------



## albertmuc

Does the "Icon Audio HP8 MkII Signature" match the Audeze LCD-X with its 20 ohms...  
- would it be a recommended combination 🤔  

Alternatively, I have my eye on White Bird Amplification's products.


----------



## WorksUnit

albertmuc said:


> Does the "Icon Audio HP8 MkII Signature" match the Audeze LCD-X with its 20 ohms...
> - would it be a recommended combination 🤔


I use 20-Ohm Quad Era-1 with it, no issue.


----------



## WorksUnit

Are owners using the Mono switch...What do you think about it?


----------



## The Jester (Mar 11, 2022)

Same here,
And really good combination they are ..👍
Haven’t tried it in mono, have a couple of old mono LPs it could be ok with ?


----------



## musicus

albertmuc said:


> Does the "Icon Audio HP8 MkII Signature" match the Audeze LCD-X with its 20 ohms...
> - would it be a recommended combination 🤔
> 
> Alternatively, I have my eye on White Bird Amplification's products.


The pairing is just fine, on all 3 impedance settings, no hum, good power, fantastic sound.


----------



## JonT

WorksUnit said:


> Are owners using the Mono switch...What do you think about it?


I have a turntable only system (with a stereo cartridge) and I've used the switch with mono LPs. I can't profess to have heard any difference.

I've found the mono switch very useful during cartridge azimuth set up (using the HiFi News Test Record).

My previous phono stage (Graham Slee Accession) had a mono switch, and I never felt I could hear a difference when playing mono LPs with that engaged either.


----------



## Progrocker111

Hi folks,

I am considering to buy this amp, but i am a bit concerned, if the amps output volume will be sufficient for Hifiman Arya planars (900mW) I am using hybrid Schiit Lyr 3 now, which is really very powerful amp and i really like to listen very loudly...

Is the HP8 amp capable to drive Aryas to loud volumes?

Many thanks for answer.


----------



## jujuju

Hi,
Sorry to go off topic..I just wanted yo let you all know that I have just put a icon audio hp8 mk2 with some nice tubes up for sale..


----------



## Coztomba (Apr 15, 2022)

Progrocker111 said:


> Hi folks,
> 
> I am considering to buy this amp, but i am a bit concerned, if the amps output volume will be sufficient for Hifiman Arya planars (900mW) I am using hybrid Schiit Lyr 3 now, which is really very powerful amp and i really like to listen very loudly...
> 
> ...


Way late to reply probably but I would not recommend it for the Arya's.  I can only comment on the Sundara's. Listening to Melody Gardot - Wayfering Stranger live. Listening quite loud on the HD800s, when the double bass cuts in, it's full and it's tight and it's handled just fine.  When I switch to the Sundara (on the HP8)... it just flubs out.  When I plug the Sundara into the Burson Soloist and volume match the Sundara does just fine (fuller than the HD800s as they are a little bass light).  That's high gain on the Soloist, 50+ volume.  I think the Hifiman cans just love current and the Arya would be worse that the Sundara in that regard. 

Just my opinion.  I LOVE the amp for dynamic headphones, but it wouldn't be my go to for planers.


----------



## JonT (Sep 13, 2022)

After owning an HP8 MkII SE for 12 months - with lots of use out of it - in a vinyl only rig into HD800S, I decided to try some new tubes.

My SE edition from stock came with Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.

The Shuguangs never did seat very firmly, I have to say.

On considering new tubes, I telephoned Icon Audio and ended up speaking with David Shaw.

According to Mr Shaw, the circuit design of the HP8 has a wide tolerance for either less-than-perfect matching of the power tubes or degradation over time of tube performance.

Moreover, Mr Shaw made the point that the circuit as a whole - rather than simply the tube component - is responsible for the tonality, dynamics, and so forth of the amplifier. He even stated - and I hope I am not being indiscreet - that he "cannot hear differences" when tube rolling the HP8... Quite an admission, given that the SE version is sold as an upgrade in terms of tubes and capacitors (perhaps this is understood as capacitors influencing tonality, tubes only as a matter of mechanical integrity or longevity?)

Members here on Head-Fi - conversely - claim that tube rolling is VERY AUDIBLE in the HP8... What are we to make of this difference of opinion between designer and end user?

Well, today I rolled in Psvane CV181-T MKII (aka. 6SN7 GT) power tubes (the ones with the grey coating) and a Genelex Gold Lion 12AX7.

(Taken together, quite bit more expensive over the stock tubes with the SE version as shipped.)

What a disappointment! My HP8 is now rendered much, much worse!

Regardless of what Mr Shaw claims - and I mean this with all due respect - the HP8 is, very obviously, affected by tube rolling: noise floor is appears identical, as does the excellent channel matching (recall, I'm running a vinyl only rig). However, frequency response is HUGELY altered. To offer an example, the MoFi 45RPM "Brothers In Arms" is famously punchy in the low frequencies (to the extent that some turntable/cartridges had tracking issues on side 2). The HD800S are known for being bass shy. Yet with the stock Shuguang/EH tubes, my HD800S would literally PUMP on my head in with low frequency energy. Since rolling in the Psvanes/Genelex, the low end is now absent on "Brothers In Arms" - so imagine how insipid less bass-y recordings sound??? Moreover, the midrange is grainy and recessed.

Now, I appreciate some might cite the necessity of "burn in" - and no doubt this is quite true of capacitors (for example) that must undergo structural changes in the first tens/hundreds of hours, but is surely less relevant to tubes (which burn-out rather than burn-in, mechanically and electrically).

YMMV, of course - but my experience is that, yes, rolling tubes is audible in the HP8... and worsening is just as probable an outcome as improvement, in terms of system synergy even with putatively superior tubes. (Although at least the Psvanes actually seat firmly!)


----------



## gimmeheadroom

jonathan c said:


> I bet that if your phone were tube-driven it would take better pictures! 😜😆…


You don't need a tube phone as long as you have a tube USB charger.. Duh!


----------



## WorksUnit

@JonT appreciate the input regarding the 800S, maybe not inevitable treble cannons...


----------



## geoffalter11

JonT said:


> After owning an HP8 MkII SE for 12 months - with lots of use out of it - in a vinyl only rig into HD800S, I decided to try some new tubes.
> 
> My SE edition from stock came with Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> ...


I also own an HP8 Signature MK2.  I also spoke with David Shaw about tube rolling.  His response to me was a bit different, but not entirely dissimilar.  He told me that the transformer and circuit provided 80-90% of the amps sound, and that tube rolling would not necessarily change the sound quality but could change the flavor up to the tolerances of the tubes.  Which tends to be 5-10%.  I have extensively rolled tubes and can provide my findings.  However, I want to say upfront that David Shaw has been nothing short of spectacular to deal with and that the HP8 is an absolute marvel.  I have yet to hear a better tube amp under $3000.  I absolutely love the amp and find that its bass response is the best I've heard in a tube amp.  The midrange is articulate and open with a gentle tube warmth, and the treble with the right tube compliment can change by audible levels.  Here are my thoughts on tubes:

@Pharmaboy also owns this amp and can discuss this topic as he and I have spent hrs figuring out the best configurations.  We are still learning but can provide some insight.

Mine came with the Ceramic Bottom CV-181 David Shaws.  They are a beautiful Psvane CV-181 that was made specifically for Icon and the HP8.  It also came with a 12AX7 EH Russian Made.  This tube is not very good.

1. The driver tube (12AX7) has more impact on the sound in my experience.  The amp can also use a 12AT7 which lowers the gain by 40db.  I have found the 12AT7 to be a significant upgrade in staging, imaging and overall coherence.
2. The Power Tubes definitely impart different flavor with different tubes.  How much depends on the tubes.
3. Synergy between the driver and power tubes is critical.  If you are using a tonally fat or euphonic driver tube you would want to balance with a more neutral power tube and vice versa.

These are my impressions and should be taken as YMMV.  All impressions are within the 5-10% tolerances that David Shaw professed.  This is a significant amount of opportunity for sound differences.  

Tubes I have for the HP8:
*12AX7/12AT7*
1. 12AX7 EH Russian Made - came with amp and I don't currently use it.
2. RCA NOS 12AX7A 1960's - This tube is wonderful.  Beautiful imaging and tonally very sweet.  The sound has that RCA NOS sweetness and bass authority while being extremely clean.
3. Brimar CV455 Footscray 1956 (12AT7) - I love this tube.  It is extremely musical and lovely.  It cuts down the gain which improves the dynamic range and opens up the stage.
4. Mullard 6201 (12AT7) - Typical Britain Mullard sound with vibrancy and warmth.
*CV-181/6SN7 Variants:*
1. CV-181 Ceramic Bottoms - The David Shaw spec tube with the Signature Version.  A great tube with a beautiful midrange and amazing bass.  I found this tube to have a bit of microphony which led me tube roll.
2. Tung Sol New Production 6SN7GTB Russian Made Cryogenically Treated - Just got these and currently burning them in.  They sound sweet with extended treble and nice bass and midrange cohesion.  Imaging is quite nice.
3. RCA NOS 1950's Narrow Gap Plate 6SN7GTB - The best tube I own for this amp.  They are amazing!  The sound is addictive with a wide and deep soundstage and amazing imaging qualities while possessing that RCA NOS bass response they are known for.

*Pairings:*
Most importantly, which tubes work with each other is the key in my opinion.  My favorite combos are as follows...
1. Brimar CV455 12AT7 driver with the RCA Narrow Gaps
2. Mullard 6201 12AT7 with the RCA Narrow Gaps
3. RCA 12AX7A NOS with the Tung Sol 6SN7GTB New Production Cryos
4. CV-181 Ceramic Bottoms with the Brimar CV455 (12AT7) NOS or RCA 12AX7A NOS
I could easily live with any of these combos and feel the am sounds holographic, musical and just about perfect.  Hope this helps...


----------



## Pharmaboy

Didn't even realize this thread was here...delighted to find it. The HP8 is outstanding & should be talked about more IMHO.

Re power, the HP8 has more grunt that I'm used to with tube amps. It easily powers everything I have, including planars. Even my beast planar, the ZMF Ori, barely gets to 9:30 on the volume dial before it's too loud. To echo what @Coztomba said above, this may not be the best amp for planars, but it's a killer amp for dynamics of any impedance.

(will have more to say about this as my tube rolling experiments progress)


----------



## WorksUnit

geoffalter11 said:


> 1. The driver tube (12AX7) has more impact on the sound in my experience. The amp can also use a 12AT7 which lowers the gain by 40db. I have found the 12AT7 to be a significant upgrade in staging, imaging and overall coherence.


That is interesting


----------



## Pharmaboy

WorksUnit said:


> That is interesting


It certainly is. I'm finding 12AT7s better in every way for this amp.

It's also fortunate for the wallet of the tube-roller, as NOS 12AT7s as a class seem to be slightly less sought after (and their prices somewhat less kited up) than NOS 12AX7s.


----------



## geoffalter11

Pharmaboy said:


> It certainly is. I'm finding 12AT7s better in every way for this amp.
> 
> It's also fortunate for the wallet of the tube-roller, as NOS 12AT7s as a class seem to be slightly less sought after (and their prices somewhat less kited up) than NOS 12AX7s.


Yes, they happen to be about half the cost for the same quality tubes. 

Check out the RFT 12AT7 NOS on eBay for $15 each. Great tube from a great seller. BullzTubez on eBay also has a great collection of 6SN7s and 12AT7 and 12AX7s. All platinum matched and very reputable.


----------



## geoffalter11

I also have a couple on the way.  A pair of matched Raytheon VT-231s, which are considered a holy-grail 6SN7 variant and are vintage 1945 tubes.  I am so EXCITED for these to arrive end of the week.  I also have a Telefunken 1950's 12AT7 Gray Wing Plate with Diamond Print on the bottom which is supposed to be sensational.  The telefunken was only $59 which I thought was a steal for the quality and age of the tube.  The Raytheon's were my biggest tube investment thus far and I will update the thread once they both come and I can roll them into my HP8.  I imagine I will use a mixture of pairings for different music depending on my mood.  Either way, the HP8 sounds incredible.

I love this amp!  @Pharmaboy and I have one more tube forthcoming.  A GE 12AX7 5751 NOS with triple mica plates.  The 5751 is another great 12AX7 option as it has 30db less gain.   Lots of fun to be had... After the 5751 I will stop and just try to enjoy and learn as the tubes evolve with the HP8.


----------



## WorksUnit

I keep stumbling upon mentions of OTL amps on head-fi, is there any value in owning one of these as well?


----------



## Pharmaboy

WorksUnit said:


> I keep stumbling upon mentions of OTL amps on head-fi, is there any value in owning one of these as well?


If you own high impedance dynamic headphones, there absolutely is value in owning an output transformerless amp. The ideal impedance match between one of these headphones and a good OTL amp sounds to me like a calmer, more stable sonic profile of the basic headphone sound you're already familiar with. It's a subtle thing, but as with so much in audio, once you hear it, you can't unhear it. 

I have a modest OTL (Woo WA3) which does sound very good on my ZMF high impedance dynamics. You needn't spend huge bucks to get a decent OTL, though as with anything else, the more you spend, the more you'll probably get.


----------



## geoffalter11

WorksUnit said:


> I keep stumbling upon mentions of OTL amps on head-fi, is there any value in owning one of these as well?


You should talk to @Mike C .  He is in the UK and builds OTL amps.  He is a wealth of knowledge and an extremely nice guy.


----------



## geoffalter11

Tube Update:

I burned in the Tung Sol 6SN7GTB New Prod Cryos for 24 hrs and they sound sensational in the HP8.  I have them paired with the Brimar CV455 12AT7 in the driver position and the combo is sublime.  The TS's are extremely clean and silky smooth up top.  This marries well with the warmth of a NOS Brimar tube.  I cannot speak highly enough about this amp.  it is slowly overtaking my Cembalo Labs Spring 1 as my go to amp.


----------



## geoffalter11

JonT said:


> After owning an HP8 MkII SE for 12 months - with lots of use out of it - in a vinyl only rig into HD800S, I decided to try some new tubes.
> 
> My SE edition from stock came with Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> ...


I hope you find your right tube compliment.  Try a NOS 12AT7.  The Brimar CV455 can be had for 45 euro on eBay.  I believe they are based out of the UK.  @jonathan c turned me onto the CV455 Brimar Footscray, the Mullard 6201 and the Tung Sol New Production 6SN7GTBs.  For a new production it is great.


----------



## WorksUnit

Found that Brimar CV455, mine should arrive in a couple of days. 
No complaints with the David Shaw CV181 and Mullard 12AX7 combination I have, but for 50 quid why not roll some dice


----------



## jonathan c

https://www.head-fi.org/threads/the-reference-6sn7-thread.117677/post-17143824


----------



## jonathan c

For those interested in a great 12AT7 versus a 12AX7…


----------



## gimmeheadroom

I'm pretty sure you guys in America can buy from English shops cheaper than we can


----------



## jonathan c

gimmeheadroom said:


> I'm pretty sure you guys in America can buy from English shops cheaper than we can


Certainly with the strength of USD vs GBP and vs EUR…


----------



## gimmeheadroom

jonathan c said:


> Certainly with the strength of USD vs GBP and vs EUR…


No, it's import duties, customs fees, imaginary charges du jour. Basically, when you buy "luxury" goods i.e. anything that costs more than 135 euros including shipping price, you become EU enemy of the state...


----------



## JonT

I wonder what the wider impact across the circuit is when swapping out the 12AX7 for a 12AT7?

As I understand it, it's not only that the 12AT7 has lower gain but also has different voltage and plate dissipation - this must then influence how the power tubes and transformer respond in the circuit?

Is there any potential for harm by rolling in a 12AT7?


----------



## Pharmaboy (Sep 17, 2022)

JonT said:


> I wonder what the wider impact across the circuit is when swapping out the 12AX7 for a 12AT7?
> 
> As I understand it, it's not only that the 12AT7 has lower gain but also has different voltage and plate dissipation - this must then influence how the power tubes and transformer respond in the circuit?
> 
> Is there any potential for harm by rolling in a 12AT7?


It says right in the Icon Audio manual's "Specifications and Features" page:

"• 1x ECC83/12AX7 first stage valve​• *Or use ECC81/12AT7 compatible for lower gain*"​
I doubt Icon Audio would say this if an 12AT7 driver could harm the circuit.

After playing around with a couple 12AX7s to start with (one was a very good NOS Telefunken), I went to 12AT7s to drop the gain a bit (I have system gain issues to start with). 

It's very subtle, but I think 12AT7s bring out a little more finesse, dynamics, and space than even great 12AX7s. I'm playing around with several top NOS 12AT7s (right now it's the 1056 Brimar CV4033), and the sound just keeps getting better.


----------



## The Jester

Is yours the “SE” version with factory cap upgrade ?


----------



## Pharmaboy (Sep 17, 2022)

The Jester said:


> Is yours the “SE” version with factory cap upgrade ?


Yes & no. The SE version has several things the stock version does not: 2 David Shaw white ceramic CV181 (6SN7) output tubes, 1 Gold pin 12AX7 input tube and Mundorf coupling capacitors. The stock unit has brown-bottom Shaw CV181s, a JJ input tube, and standard coupling caps (I don't know what brand).

I rolled NOS tubes in all 3 tube positions anyway, so that doesn't matter to me. The previous owner had an electronics tech change the coupling caps to Mundorfs.


----------



## The Jester

The Jester said:


> Only an hour here and there so far,
> 12AX7 Is an EH gold which I don’t mind, tried both those and Gold Lion 6992’s in my CJ preamp and slightly preferred the EH ...
> 2021 here already so Happy New Year and a quick photo ....


Had mine a while now and still no urge to go tube rolling ….. yet … when the prices return to sane levels I might try a Gold Lion 12AX7 🤔
Nice you already have the upgraded Mundorf caps before some tube experimenting … 👍


----------



## Pharmaboy

The Jester said:


> Had mine a while now and still no urge to go tube rolling ….. yet … when the prices return to sane levels I might try a Gold Lion 12AX7 🤔
> Nice you already have the upgraded Mundorf caps before some tube experimenting … 👍


The driver tube that came with mine is a Gold Lion 12AX7 the previous owner bought. It's a pleasant tube, for sure.

I'm discovering that so much of the HP8's excellent sound comes from the driver. In the next day or two I'll try a Brimar NOS CV455, a pair of which I've been burning in (w/6922-to-12AT7 adapters in my Woo WA3 OTL amp). Those CV455s are providing the most dramatic sonic makeover I could have imagined for the WA3. If the CV455 tube does for the HP8 anything like what it's doing for the WA3, I'll be one happy fellow.

Best part: you can get a CV455 for a little over $50 US, not much more than what the Gold Lion costs. 

_(to be continued)_


----------



## jonathan c

Pharmaboy said:


> The driver tube that came with mine is a Gold Lion 12AX7 the previous owner bought. It's a pleasant tube, for sure.
> 
> I'm discovering that so much of the HP8's excellent sound comes from the driver. In the next day or two I'll try a Brimar NOS CV455, a pair of which I've been burning in (w/6922-to-12AT7 adapters in my Woo WA3 OTL amp). Those CV455s are providing the most dramatic sonic makeover I could have imagined for the WA3. If the CV455 tube does for the HP8 anything like what it's doing for the WA3, I'll be one happy fellow.***
> 
> ...


*** ask @geoffalter11 …


----------



## JonT

The Jester said:


> Had mine a while now and still no urge to go tube rolling ….. yet … when the prices return to sane levels I might try a Gold Lion 12AX7 🤔
> Nice you already have the upgraded Mundorf caps before some tube experimenting … 👍



Your mileage may vary, but when I swapped out the stock EH Gold Pin 12AX7 for a Gold Lion 12AX7 to my ears - inside HD800S - the whole feel, frequency response, and dynamics took a dramatic turn for the worse. In particular, the low end evaporated (not a helpful outcome for HD800S) and the midband became extremely thin. Up until that point, I'd prized the HP8 for the way it had added such body and timbre whilst retaining inner detail and dynamics. After living with the Gold Lion for a few listening sessions, the EH went back into V1 and the problem was resolved.


----------



## JonT

Pharmaboy said:


> It says right in the Icon Audio manual's "Specifications and Features" page:
> 
> "• 1x ECC83/12AX7 first stage valve​• *Or use ECC81/12AT7 compatible for lower gain*"​
> I doubt Icon Audio would say this if an 12AT7 driver could harm the circuit.
> ...


Thanks @Pharmaboy - my bad for not re-checking the manual!

(and quite a kooky manual at that! - digging the Windows 97 typeface!)


----------



## The Jester

JonT said:


> Your mileage may vary, but when I swapped out the stock EH Gold Pin 12AX7 for a Gold Lion 12AX7 to my ears - inside HD800S - the whole feel, frequency response, and dynamics took a dramatic turn for the worse. In particular, the low end evaporated (not a helpful outcome for HD800S) and the midband became extremely thin. Up until that point, I'd prized the HP8 for the way it had added such body and timbre whilst retaining inner detail and dynamics. After living with the Gold Lion for a few listening sessions, the EH went back into V1 and the problem was resolved.


Thanks for sharing ..👍
Not in any hurry to start tube rolling just yet, I much prefer the 6992 gold lions over the EH gold in my preamp, but that’s different valves used in one pair per channel for the output stage, where my system is right now all I’m doing lately is buying more music … 😃


----------



## geoffalter11

WorksUnit said:


> Found that Brimar CV455, mine should arrive in a couple of days.
> No complaints with the David Shaw CV181 and Mullard 12AX7 combination I have, but for 50 quid why not roll some dice


Let us know how the CV455 works out.  Hoping you love it!


----------



## geoffalter11

jonathan c said:


> *** ask @geoffalter11 …


The CV455 is a revelation.  A truly wonderful driver tube with incredible musicality, slight warmth, and perfect harmonics.  The lower gain has not affected the volume, but has opened up the soundstage and provided a more insightful sound. 

@jonathan c & @Pharmaboy have become my tube rolling buddies with the HP8. I now have a pretty nice collection of both 12AT7/12AX7s and 6SN7s.  Honestly, I like them all.  I just like this amp.  No other way to slice it.  This amp is just incredible.  Right now I am using a 1950's Telefunken Grey Plate 12AT7 and a pair of Raytheon VT-231s. The sound is nothing short of perfect to my ears.  I am listening to my Auteur OG and wondering where this sound has been my whole life.


----------



## Pharmaboy

geoffalter11 said:


> I now have a pretty nice collection of both 12AT7/12AX7s and 6SN7s.


Understatement!

Yes, I'm having fun rolling tubes in not just the HP8, but also the Woo WA3 where, thanks to @jonathan c's advice, I recently had a breakthrough with these terrific Brimar CV455 + adapters.

Up until the last couple weeks, most of my tube rolling experiments didn't pan out. Things seem to be turning around.

It surely doesn't hurt that the HP8 (which I'd never seen or heard before buying one F.S.) is obviously a rock-solid design with the best transformer I've encountered, huge power for a 3-tube design, the best bass I've heard in any tube amp, and real responsiveness to tube rolling. The sound seems just as solid as the design, no matter what tubes are used.


----------



## geoffalter11

Pharmaboy said:


> Understatement!
> 
> Yes, I'm having fun rolling tubes in not just the HP8, but also the Woo WA3 where, thanks to @jonathan c's advice, I recently had a breakthrough with these terrific Brimar CV455 + adapters.
> 
> ...


It is such a wonderful amp. Great feedback and awesome to hear the optimism for what’s to come.


----------



## geoffalter11

geoffalter11 said:


> It is such a wonderful amp. Great feedback and awesome to hear the optimism for what’s to come.


And yes @jonathan c has provided countless hours of fun and learning with his knowledge and generosity.  He is a wealth of knowledge and has helped me to transform what was already a wonderful amp into something exponentially better.  Next stop, Synergistic Research Purple Fuse!


----------



## jonathan c

geoffalter11 said:


> And yes @jonathan c has provided countless hours of fun and learning with his knowledge and generosity.  He is a wealth of knowledge*** and has helped me to transform what was already a wonderful amp into something exponentially better.  Next stop, Synergistic Research Purple Fuse!


*** because of Head-Fiers such as bcowen, Paladin79, L0rdGwyn, WesS, LoriWiv, Ripper2860, Pharmaboy, Until Then…and quite a few more 🙏 👍.


----------



## geoffalter11

jonathan c said:


> *** because of Head-Fiers such as bcowen, Paladin79, L0rdGwyn, WesS, LoriWiv, Ripper2860, Pharmaboy, Until Then…and quite a few more 🙏 👍.


You deflected my compliment.  Take the compliment!


----------



## WorksUnit

So, some days on the Brimar that Jonathan C linked.

I found it fatiguing on Hyland Jupiter-1s compared to Mullard 12AX7, though a revisit will happen...
What is *has* done for me, at least, is breathe new life into Quad Era-1...
Never had a better impression of drumkits in a mix, whilst still being able to nail overdrive pedals.


Fantastic suggestion, secret tube rolling cabal


----------



## Pharmaboy

WorksUnit said:


> secret tube rolling cabal


Dark imagination!

Human sacrifice is not a part of my tube rolling. Of course, I can't speak for the others...


----------



## jonathan c

Pharmaboy said:


> Dark imagination!
> 
> Human sacrifice is not a part of my tube rolling. Of course, I can't speak for the others...


…..In the catacomb where the rolling is undertaken (😣), fingertip sacrifice is possible if haste is excessive….😳🤪….


----------



## gimmeheadroom

Pharmaboy said:


> Dark imagination!
> 
> Human sacrifice is not a part of my tube rolling. Of course, I can't speak for the others...



Don't get carried away- he meant to write cable! Cabal was just a typo


----------



## Pharmaboy

gimmeheadroom said:


> Don't get carried away- he meant to write cable! Cabal was just a typo


Color me disappointed...


----------



## WorksUnit

gimmeheadroom said:


> Don't get carried away- he meant to write cable! Cabal was just a typo


_As if.._ you naughty boy 


Pharmaboy said:


> Color me disappointed...


What is not disappointing though is that CV455, *bloodhound mode* activated on that valve code..


----------



## geoffalter11

WorksUnit said:


> _As if.._ you naughty boy
> 
> What is not disappointing though is that CV455, *bloodhound mode* activated on that valve code..


I love the CV455 Footscray. Great tube in the HP8


----------



## jonathan c

geoffalter11 said:


> I love the CV455 Footscray. Great tube in the HP8


…and in the LTA MZ3, QSA, Woo WA2, WA3, WA6….☁️☁️☁️☁️😊


----------



## geoffalter11

jonathan c said:


> …and in the LTA MZ3, QSA, Woo WA2, WA3, WA6….☁️☁️☁️☁️😊


In other words, kick ass tube…


----------



## jonathan c

geoffalter11 said:


> In other words, kick _gl_ass tube…


FTFY…[Reg. TM; © bcowen: 2021.]


----------



## geoffalter11

I am currently having the best listening session yet with the HP8.  The RCA 6SN7GTB Narrow Gaps are in full flight, and I have burned in the Mullard 6201 Gold Pins for the past 24 hrs.  This amp is an absolute marvel.  I can't get enough of how it sounds.  I never thought I would put something in front of my Cembalo Spring 1, but it has become my go to amp.  It deserves every accolade.


----------



## jonathan c

I am happy to be an Iconaudioclast! The HP8 is breaking in with Caliente! by Gato Barbieri. Tubes are Zalytron 5692 pair plus RCA black plate 12AX7 - all on tube risers (socket savers). The HP8 has been ‘turboed’ with a SR Purple Fuse. I chose the sensitive and excellent Grado RS-1x to evaluate HP8 susceptibility to hum. More to follow:


----------



## Pharmaboy

jonathan c said:


> I am happy to be an Iconaudioclast! The HP8 is breaking in with Caliente! by Gato Barbieri. Tubes are Zalytron 5692 pair plus RCA black plate 12AX7 - all on tube risers (socket savers). The HP8 has been ‘turboed’ with a SR Purple Fuse. I chose the sensitive and excellent Grado RS-1x to evaluate HP8 susceptibility to hum. More to follow:


Welcome to the HP8 club...small but select.

Tube riser is a great idea. I've grown concerned about frequent swaps of driver tubes stressing the socket. Think I need a tube riser for the driver tube, at the least. 

Where'd you get yours?


----------



## jonathan c

Pharmaboy said:


> Welcome to the HP8 club...small but select.
> 
> Tube riser is a great idea. I've grown concerned about frequent swaps of driver tubes stressing the socket. Think I need a tube riser for the driver tube, at the least.
> 
> Where'd you get yours?


•  The tube risers (socket savers) also permit better heat dissipation from the tube glass. I would also get them for the 6SN7s: if you roll those, you will be able to grip them by the micanol base rather than by the glass - thereby avoiding detachment from the base.
•  Amplified Parts (direct / via Amazon):


----------



## jonathan c (Oct 6, 2022)

•  First things first. The initial (current) tube configuration is pair Zalytron 5692 plus single RCA black plate 12AX7. Hum is just very faint at maximum volume / no music. Break-in time thus far: almost thirteen hours.
•  Right now, I am listening to Dexter Gordon on the album _Stable Mable _(released 1990, Steeplechase Records: Denmark). This is a great album: studio but with club feel. [A must listen].
•  The HP8 rendition of this is astounding…live…goosebumps…The tube combination is absolutely felicitous / serendipitous…on the first try, no less! Bass is sinuous, tenor sax is throaty with the ‘right bite’, piano & drums are there!
•  I have listened to (been swept away by) this album many times and can say that this HP8 configuration _for me_ surpasses the QSA and Woo WA6 (two h/p/a which I love) in ‘bringing the 🎵 goods home’.
•  I have been listening only via Grado RS-1x. Wait until the ZMFs, the armada of 12AT7 tubes (‘Footscray’, RFT, Tungsram…), and Ken Rad VT-231s, Melz 6N8Ss…😀🤪…


----------



## geoffalter11

jonathan c said:


> •  First things first. The initial (current) tube configuration is pair Zalytron 5692 plus single RCA black plate 12AX7. Hum is just very faint at maximum volume / no music. Break-in time thus far: almost thirteen hours.
> •  Right now, I am listening to Dexter Gordon on the album _Stable Mable _(released 1990, Steeplechase Records: Denmark). This is a great album: studio but with club feel. [A must listen].
> •  The HP8 rendition of this is astounding…live…goosebumps…The tube combination is absolutely felicitous / serendipitous…on the first try, no less! Bass is sinuous, tenor sax is throaty with the ‘right bite’, piano & drums are there!
> •  I have listened to (been swept away by) this album many times and can say that this HP8 configuration _for me_ surpasses the QSA and Woo WA6 (two h/p/a which I love) in ‘bringing the 🎵 goods home’.
> •  I have been listening only via Grado RS-1x. Wait until the ZMFs, the armada of 12AT7 tubes (‘Footscray’, RFT, Tungsram…), and Ken Rad VT-231s, Melz 6N8Ss…😀🤪…


Welcome to the fabulous world of Icon's HP8 MK2 Signature.  It is a seriously wonderful amp.  You have a great combo of tubes in the HP8 for your first listen.  Can't wait to hear how you like the footscray and VT-231s.

I have been using the Raytheon VT-231s with the RCA 12AX7A as of late and have been loving it. Sorry to hear the HP8 is making your QSA and WA6 obsolete, but thrilled you are enjoying the HP8 so much on day one. Just gets better....


----------



## Pharmaboy

jonathan c said:


> •  The tube risers (socket savers) also permit better heat dissipation from the tube glass. I would also get them for the 6SN7s: if you roll those, you will be able to grip them by the micanol base rather than by the glass - thereby avoiding detachment from the base.
> •  Amplified Parts (direct / via Amazon):


Great info. Thanks!

So the P-ST9-900's pins fit 12AX7/12AT7/CV533s? (dumb question)


----------



## jonathan c

Pharmaboy said:


> Great info. Thanks!
> 
> So the P-ST9-900's pins fit 12AX7/12AT7/CV533s? (dumb question)


Those are general nine-pin adapters: will fit. [There is probably a 1940s industry manual that specifies the length, width, separation of the pins and set those as standard.]


----------



## jonathan c

After a most auspicious debut in my system, HP8 is keeping the Zalytron 5692 pair and will use the Brimar CV455 (KB/FB 1956: Footscray).   


The following lyric from _West Side Story _comes to mind as warm-up begins shortly…


----------



## jonathan c (Oct 7, 2022)

…in the middle of _The Best of Stephanie Mills_ via the Beyerdynamic DT-880 (600 ohms). This headphone is usually a ‘toughie’ - high impedance, mid/low sensitivity; wonderful when ‘fed right’.
•  My word! What a job HP8 does with the DT! Ambience, clarity, dynamics, ease, evenness, focus, heft, openness…..power to spare. With the high impedance setting, the volume knob does not get past ‘eleven o’clock’. Even the Woo WA2 (OTL) has to have a ‘later’ volume setting. Plus, the bass reproduction from HP8 runs more deeply and tightly than that from WA2.
•  In sum, I am enthralled that HP8 can ‘coax’ this level of sonic performance from such a ‘recalcitrant’ headphone. ZMFs should be _real treats_ with HP8…😛…


----------



## jonathan c

And onwards to ZMF Atrium…. 

 • What to make of HP8 / Atrium?….Think Bogart & Bacall, think Astaire & Rogers….The _‘chemistry’ _between the two is astounding.
•  HP8 brings out all the Atrium virtues (which have been well covered in Head-Fi) in a manner which brings to mind: ‘we hold these truths to be self-evident’. Obvious is obvious, subtle is subtle. In effect, I ask myself: ‘_should _I even be using another h/p/a for Atrium?’.
•  The music, with all its cadences, dynamics (and even mistakes) is conveyed by HP8 with absolute assurance & veracity. Audiophile checklist? What else can be said?
• To feel this way about HP8 after listening via a trio of headphones as varied as Beyer DT-880 (600 ohms), Grado RS-1x, and ZMF Atrium is easy. Such is the HP8.


----------



## geoffalter11

jonathan c said:


> And onwards to ZMF Atrium….  • What to make of HP8 / Atrium?….Think Bogart & Bacall, think Astaire & Rogers….The _‘chemistry’ _between the two is astounding.
> •  HP8 brings out all the Atrium virtues (which have been well covered in Head-Fi) in a manner which brings to mind: ‘we hold these truths to be self-evident’. Obvious is obvious, subtle is subtle. In effect, I ask myself: ‘_should _I even be using another h/p/a for Atrium?’.
> •  The music, with all its cadences, dynamics (and even mistakes) is conveyed by HP8 with absolute assurance & veracity. Audiophile checklist? What else can be said?
> • To feel this way about HP8 after listening via a trio of headphones as varied as Beyer DT-880 (600 ohms), Grado RS-1x, and ZMF Atrium is easy. Such is the HP8.


What a cool post. Atrium and HP8 makes me happy too. HP8 and just about everything makes me happy.


----------



## geoffalter11

@Paladin79 made me a pair of RCA interconnects for my HP8.  It needed a better set of wire.  My Blue Dragon RCAs were 5 yrs old and falling apart.  Just another reason to love this amp.  it scales to whatever you give it.  I have this desire to get another tube amp because the HP8 sounds so good.  I automatically think, if the HP8 sounds this good, what will a Stellaris sound like.  Bottom line, the HP8 is more than enough.  You nailed its sound by saying that it is dynamic, veracious, and just easy.  Tonight is the Auteur Classic in all its glory.  Raytheon Vt-231s and the Telefunken 1950s Grey Plate 12AT7 are a fantastic pairing.


----------



## The Jester

When something like the HP8/ signature is in the system you may hear a difference in everything, tubes, source, interconnects, power cables …


----------



## Pharmaboy

jonathan c said:


> And onwards to ZMF Atrium….  • What to make of HP8 / Atrium?….Think Bogart & Bacall, think Astaire & Rogers….The _‘chemistry’ _between the two is astounding.
> •  HP8 brings out all the Atrium virtues (which have been well covered in Head-Fi) in a manner which brings to mind: ‘we hold these truths to be self-evident’. Obvious is obvious, subtle is subtle. In effect, I ask myself: ‘_should _I even be using another h/p/a for Atrium?’.
> •  The music, with all its cadences, dynamics (and even mistakes) is conveyed by HP8 with absolute assurance & veracity. Audiophile checklist? What else can be said?
> • To feel this way about HP8 after listening via a trio of headphones as varied as Beyer DT-880 (600 ohms), Grado RS-1x, and ZMF Atrium is easy. Such is the HP8.


"Such is the HP8" (indeed!)

Which impedance setting did you use w/the Atrium?


----------



## geoffalter11

Pharmaboy said:


> "Such is the HP8" (indeed!)
> 
> Which impedance setting did you use w/the Atrium?


High all the way.  No other choice, in my opinion... I use the M for my low impedance headphones.  My Radiante and 4z are absolutely dead quiet and perfect on the M setting.  

What about you Peter and Jonathan?  This thread is finally getting its due.  This amp is a serious contender for End Game!


----------



## Pharmaboy

I've done most of my listening to the HP8 with my silkwood VO, a match made in heaven. I use only the high impedance setting for the VO and Aeolus.

Just ordered the 3 tube risers and will probably postpone any more tube-swapping until those show up. None of the 3 sockets in my HP8 are outright loose, but none seem as a tight & secure as they probably were new. 

Before installing the risers, I probably should figure out how to take the top cover off (it doesn't look simple or easy to do) and tighten the left & right socket screws for each  of the 3 sockets.

Anyone manage to get the top off yet?


----------



## geoffalter11

Do you have take the sockets out to put the risers in?  Or do they just fit right into the sockets of each?


----------



## jonathan c

geoffalter11 said:


> High all the way.  No other choice, in my opinion... I use the M for my low impedance headphones.  My Radiante and 4z are absolutely dead quiet and perfect on the M setting.
> 
> What about you Peter and Jonathan?  This thread is finally getting its due.  This amp is a serious contender for End Game!


High for Beyer, Senn, ZMF; Medium for Focal Clear; Low for Audeze LCD-X, Gjallarhorn, Grado.


----------



## Pharmaboy

geoffalter11 said:


> Do you have take the sockets out to put the risers in?  Or do they just fit right into the sockets of each?


They fit right into current sockets: male pins are on the bottom (inserting into orig. tube socket) & female pins on top (to accept pins of the tube that goes in that socket).


----------



## jonathan c (Oct 8, 2022)

Pharmaboy said:


> I've done most of my listening to the HP8 with my silkwood VO, a match made in heaven. I use only the high impedance setting for the VO and Aeolus.
> 
> Just ordered the 3 tube risers and will probably postpone any more tube-swapping until those show up. None of the 3 sockets in my HP8 are outright loose, but none seem as a tight & secure as they probably were new.
> 
> ...


I wouldn’t tamper with the copper plate. It adds mass and rigidity to the HP8 surface: adds shielding and probably helps to eliminate amplifier microphonics.


----------



## Jay Smith

jonathan c said:


> And onwards to ZMF Atrium….  • What to make of HP8 / Atrium?….Think Bogart & Bacall, think Astaire & Rogers….The _‘chemistry’ _between the two is astounding.
> •  HP8 brings out all the Atrium virtues (which have been well covered in Head-Fi) in a manner which brings to mind: ‘we hold these truths to be self-evident’. Obvious is obvious, subtle is subtle. In effect, I ask myself: ‘_should _I even be using another h/p/a for Atrium?’.
> •  The music, with all its cadences, dynamics (and even mistakes) is conveyed by HP8 with absolute assurance & veracity. Audiophile checklist? What else can be said?
> • To feel this way about HP8 after listening via a trio of headphones as varied as Beyer DT-880 (600 ohms), Grado RS-1x, and ZMF Atrium is easy. Such is the HP8.


Very nice gears you have.  How does HP8 compared to your Woo audio amp WA2/ WA8 and Violectric V200 based on Clear?


----------



## geoffalter11

jonathan c said:


> I wouldn’t tamper with the copper plate. It adds mass and rigidity to the HP8 surface: adds shielding and probably helps to eliminate amplifier microphonics.


Agreed


----------



## geoffalter11

Pharmaboy said:


> They fit right into current sockets: male pins are on the bottom (inserting into orig. tube socket) & female pins on top (to accept pins of the tube that goes in that socket).


Thanks Peter.  I think I am going to get a set for V1, V2, and V3 as well.  I have a habit of changing the tubes a lot.  Right now Brimar CV455 and the Tung Sol New Production Cryos 6SN7GTB.  @jonathan c the TS's sound awesome.  Super smooth with incredible top end clarity.  They might be the most clear and resolving of the power tubes I have.  They don't have the same weight of the Vt-231s or Narrow Gaps, but otherwise they are just about perfect.


----------



## gimmeheadroom

jonathan c said:


> I wouldn’t tamper with the copper plate. It adds mass and rigidity to the HP8 surface: adds shielding and probably helps to eliminate amplifier microphonics.


Mostly, it eliminates cosmic rays, duh!


----------



## jonathan c

The Iconic magic continues…at H impedance setting…with ZMF Aeolus (w/ Aeolus perforated pads) which reaches new peaks in sonic performance !! Utterly enjoyable !!


----------



## jonathan c

The Aeolus / Icon duo above is ‘simply irresistible’ (robert palmer) with mid-late 1970s CTI (Creed Taylor, Inc.) released jazz / fusion albums such as:


----------



## Pharmaboy

jonathan c said:


> The Aeolus / Icon duo above is ‘simply irresistible’ (robert palmer) with mid-late 1970s CTI (Creed Taylor, Inc.) released jazz / fusion albums such as:


CTI was the label people loved or hated. Photographers loved it (the covers were huge art photo displays), but musical purists (jazz bo's) usually disdained them.

Later I realized that no matter what label Milt Jackson was on, I had to hear it.


----------



## geoffalter11

Pharmaboy said:


> CTI was the label people loved or hated. Photographers loved it (the covers were huge art photo displays), but musical purists (jazz bo's) usually disdained them.
> 
> Later I realized that no matter what label Milt Jackson was on, I had to hear it.


CTI created amazing albums like Freddie Hubbard's Red Clay.  My all time favorite jazz album.  Red Clay is such a great song.  With house musicians like Tony Williams, Milt Jackson, Herbie Hancock, Ron Carter and Freddie Hubbard, it is hard to criticize that era of jazz.  Creed Taylor left Blue Note to create some of the best jazz/fusion on the planet.


----------



## jonathan c

Pharmaboy said:


> CTI was the label people loved or hated. Photographers loved it (the covers were huge art photo displays), but musical purists (jazz bo's) usually disdained them.
> 
> Later I realized that no matter what label Milt Jackson was on, I had to hear it.


Certainly, fusion / smooth jazz had (still have?) many detractors from purists / traditionalists. The CTI albums were well produced, well recorded. At least a number of the jazz ‘biggies’ who did their CTI ‘stint’ for $$, Freddie Hubbard for one, returned to what got them there.


----------



## jonathan c (Oct 10, 2022)

geoffalter11 said:


> CTI created amazing albums like Freddie Hubbard's Red Clay.  My all time favorite jazz album.  Red Clay is such a great song.  With house musicians like Tony Williams, Milt Jackson, Herbie Hancock, Ron Carter and Freddie Hubbard, it is hard to criticize that era of jazz.  Creed Taylor left Blue Note to create some of the best jazz/fusion on the planet.


Don’t forget that Creed Taylor was no neophyte when CTI was started. He had good experience at Verve (a great jazz label!) and at A&M before CTI. Creed Taylor passed away this past August 22nd…


----------



## jonathan c (Oct 10, 2022)

geoffalter11 said:


> CTI created amazing albums like Freddie Hubbard's Red Clay.  My all time favorite jazz album.  Red Clay is such a great song**.  With house musicians like Tony Williams, Milt Jackson, Herbie Hancock, Ron Carter and Freddie Hubbard, it is hard to criticize that era of jazz.  Creed Taylor left Blue Note to create some of the best jazz/fusion on the planet.


** 🤪 ahem! If Red Clay was composed without vocals (intended), it cannot be a song…🎵🎶…😜


----------



## geoffalter11

jonathan c said:


> ** 🤪 ahem! If Red Clay was composed without vocals (intended), it cannot be a song…🎵🎶…😜


What do I call it then? 😂


----------



## geoffalter11

jonathan c said:


> Don’t forget that Creed Taylor was no neophyte when CTI was started. He had good experience at Verve (a great jazz label!) and at A&M before CTI. Creed Taylor passed away this past August 22nd…


Agreed! That was a sad day for sure. Certainly a moment where I remember what I was doing when I learned of his passing. Big loss to the world!


----------



## jonathan c

geoffalter11 said:


> What do I call it then? 😂


Red Clay


----------



## jonathan c

Iconic even when idle…


----------



## jonathan c (Oct 18, 2022)

Iconic even when handling a high impedance planar headphone. Yes, there is one: Audeze LCD-4 at 200 ohms (here in Camphor Burl): 


[The HP8 handles the LCD-4 with aplomb - dynamic, exciting & natural sound]


----------



## realmassy

I’m gonna keep an eye on this little amp: it has been around for a long time, it means it is a solid design and provides good value I think. It’s rarely discussed and compared to other amps too.
I’m more a solid state guy, I prefer clean and fast sound, the only tube amp I’ve got works fine on low impedance headphones but I don’t think is great with the HD800S. I have a ZMF Atrium coming and I suspect it won’t be a fantastic match either…we shall see.
How would you describe the HP-8 sound? Syrupy/lush or reasonably tight?


----------



## JonT

realmassy said:


> I’m gonna keep an eye on this little amp: it has been around for a long time, it means it is a solid design and provides good value I think. It’s rarely discussed and compared to other amps too.
> I’m more a solid state guy, I prefer clean and fast sound, the only tube amp I’ve got works fine on low impedance headphones but I don’t think is great with the HD800S. I have a ZMF Atrium coming and I suspect it won’t be a fantastic match either…we shall see.
> How would you describe the HP-8 sound? Syrupy/lush or reasonably tight?


I use the HP8 Mk2 SE with HD800S... in my view, the best synergy I've found (coming from an SPL Phonitor 2, Graham Slee ULDE, Pathos Aurium).

The sound is not in any sense syrupy/lush - and I'm using a vinyl source - by direct contrast with the solid state amps I've used. What is does bring, over and above the fast/clean sound you describe, is much more body, texture, and timbre versus the other amps I paired with the HD800S. My listening experience is that the famed HD800 spike is somewhat tamed by the HP8, I assume because the circuit is designed with a slight dip in the harshness region. For this reason, I find the synergy to be great.

I've also found - and I was sceptical on this - that tube rolling (of which I've done minimal) does noticeably tune the sound; meaning it is possible to to get the HP8 to lean a bit one way or the other, tonally.

Finally, the power output is phenomenal - noon on the volume pot is very loud into the HD800S.

Hope this helps!


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## realmassy

It does, thank you! I sent the company an email asking for some specs, my source has a relatively high output impedance and I haven’t found anywhere the input impedance of the HP-8.
The amp is definitely in my short list


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## JonT (Oct 23, 2022)

For 2 years - since I've had it - I used only the stock tubes supplied with my SE: Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.

Source is vinyl only: Technics SL1200G - Dynavector DV XX2 Mk2 - Cyrus Phono Signature/PSX R2 Power Supply into HD800S.

One of the CV181s went quite rustly. When I spoke with David Shaw, he was quite adamant that the circuit as a whole is key and - as I understood the conversation - he was less than convinced about many of the claims concerning tube rolling.

A few weeks ago I went with new production tubes (not supplied by Icon Audio): Psvane CV181-T MKIIs and a Genelex Gold Lion 12AX7.

With no disrespect to David Shaw, this made a HUGE difference to the frequency response of the HP8 - and, as it happens, for the worse! With the Genelex, the low end all but disappeared and what was left was grainy and strident. This was after 20 hours or so of burn-in or 'burn-in' (whatever your view).

I retained the Psvanes - which compared with the similarly priced Black Treasures are more tonally balanced and slightly more detailed - but swapped the original EH 12AX7 gold pin back in. The HP8 sounded lovely again! This seems to suggest, as others have noted, that the driver arguably has the most dramatic influence on tonality.

This week I picked up a NOS Brimar 12AX7 'red ink' (1960s, I think) and also - following the advice of others here - a NOS Brimar 12AT7 CV455 (1956).

Figuring I'd compare apples to apples first, I swapped in the Brimar 12AX7 yesterday. Left the HP8 on for a few hours then did some listening.

First impressions: I could detect no or negligible difference (across many recordings I know intimately) between the £100 NOS Brimar and the £30 new production EH. Others here may be able to speculate why the Genelex effected such dramatic change in sound while the Brimar-EH swap made negligible difference. I assume it is because the electrical performance in the circuit of the Brimar and EH is more or less indistinguishable but the Genelex performed differently (and to my ears/system synergy, less pleasingly)? In this sense, when David Shaw cautioned that buying NOS is paying for 'rarity' and not necessarily 'improvement' (or 'longevity' - time will tell), he seems to have an empirically grounded point.

I'll report back when I've tried the obviously very different current draw/gain rating 12AT7.


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## Pharmaboy (Oct 23, 2022)

JonT said:


> For 2 years - since I've had it - I used only the stock tubes supplied with my SE: Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> Source is vinyl only: Technics SL1200G - Dynavector DV XX2 Mk2 - Cyrus Phono Signature/PSX R2 Power Supply into HD800S.
> 
> ...


I think you'll find good sound with 12AT7s in general. I've been switching between 4 of them: a Mullard 6901 (still burning in and the sound is coming way up); a Brimar CV455 (huge midrange with good extension on top & bottom); a 1960s Mullard; and a 1956 Brimar CV4033 (haven't listened since burn-in complete). They each sound terrific, but rather different from each other.

The amp's baseline sound w/stock CV181s + Gold Lion 12AX7 was very good, but it got even better with NOS RCA 6SN7s plus various 12AT7 drivers mentioned above. No matter which tubes I use, the bass is exceptional for a transformer-coupled tube amp. The HP8 doesn't sound all that "tubey" in the way some amps do via spacey, diffuse soundstaging and moderate warmth. But the distinct dimensionality and 3D quality of musical notes marks this amp as tube all the way ...


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## jonathan c

JonT said:


> For 2 years - since I've had it - I used only the stock tubes supplied with my SE: Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> Source is vinyl only: Technics SL1200G - Dynavector DV XX2 Mk2 - Cyrus Phono Signature/PSX R2 Power Supply into HD800S.
> 
> ...


** The manual / other materials which accompany the HP8 MK-II state that 12AT7 tubes can be used if one desires lower gain. It seems unlikely that David Shaw would recommend 12AT7 use if it were suboptimal or harmful to performance. Also, the filament (heater) current for 12AT7 and 12AX7 are the same: 150mA when run in series, 300mA when run in parallel.


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## jonathan c (Oct 24, 2022)

I have _enjoyed _using 12AT7 tubes in ‘V1’ socket of HP8. I feel that the lower gain vs 12AX7s ‘creates more room’ between signal level and circuit clipping level. This allows music crescendos to be handled in unstrained fashion. Also, the volume knob is turned further clockwise: reducing potential for any volume pot low-level imbalance. On the 12AT7 front, I am waiting to hear from Icon Audio about use of a Marconi / M-O-V A2900 (a 12AT7 with an unusual filament current of 400mA) in the HP8…..(the tube is prodigious in LTA MZ3!).


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## geoffalter11

JonT said:


> For 2 years - since I've had it - I used only the stock tubes supplied with my SE: Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> Source is vinyl only: Technics SL1200G - Dynavector DV XX2 Mk2 - Cyrus Phono Signature/PSX R2 Power Supply into HD800S.
> 
> ...


My reaction to tube rolling with my HP8 MK2 Signature has been different. I spoke with David Shaw early on and he told me that the circuit controlled the sound not the tubes but that I could expect flavor differences up to the tolerances of the tubes. +- 5-10%.  But sound quality would be unaffected.

I have found David’s advice to be spot on. The HP8 sounds great with all tubes, however the V1 slot has been the one tube I have found the most tonal or flavor differences. I do not like the EH 12AX7. I find it to be a mediocre tube. I have had great luck with the Brimar CV455 Footscray and the Mullard 6201 (thank you Jonathan). I have also invested in a pair of RCA 12AX7As (1960s) and a 1950s 12AT7 Telefunken grey plate. 

I agree with Jonathan the 12AT7 provides more head room and better dynamic range. Not necessarily better sound quality. 

My HP8 came with CV-181 Ceramic Bottoms, a PSvane tube set. They are great tubes, but I have found them to be a bit microphonic as they don’t seat perfectly for me. My favorite pair of 6SN7s are the Raytheon VT-231. I like it with the Brimar Footscray or the Telefunken 12AT7.

However, I loved the amp before I started playing with tubes. Differences are subtle, but differences there are…


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## realmassy

How’s the amp in terms of quietness? I tend to like solid state amps because I prefer a fast and clean sound, but also because I ‘hate’ hiss and noise in the headphones. The other tube amp I use (the Manley Absolute) sounds great in linear mode but shows some background noise in triode mode. It’s also a fantastic match for my low impedance Meze Empyreans, not so match with the HD800s and ZMF Atrium.
Do you notice any noise on high impedance cans?


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## geoffalter11 (Oct 23, 2022)

My guess is that David hears or sees no difference with tubes electrically. SET amps are predominantly about the transformer. And the HP8 has a beauty. I have always known that SET amps are 90% the circuit and transformer in terms of the sound quality. There is also the fact that the tubes he has spec’d are his brand. My CV-181s are called David Shaw. He could be protecting his tube brand just the same.

I have also not ruled out the fact that I spent the money on the tubes, therefore I want them to make a difference. But, I do hear differences.

I bought the HP8 because of John Grandberg’s review in Innerfidelity years ago. The version we all have is better than what John reviewed all those yrs ago and the amp is good enough to continue winning awards 10 plus yrs after its initial design.

And who doesn’t love that copper plate? The amp is flat out gorgeous and heavy for its size with tons of power and flexibility.


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## geoffalter11 (Oct 23, 2022)

realmassy said:


> How’s the amp in terms of quietness? I tend to like solid state amps because I prefer a fast and clean sound, but also because I ‘hate’ hiss and noise in the headphones. The other tube amp I use (the Manley Absolute) sounds great in linear mode but shows some background noise in triode mode. It’s also a fantastic match for my low impedance Meze Empyreans, not so match with the HD800s and ZMF Atrium.
> Do you notice any noise on high impedance cans?


Nothing. It is dead quiet. You will not find a better tube amp in its price range. It competes with amps 1 1/2 - 2 times its price.

It is the best amp I’ve ever heard with ZMF. It really is a shame more folks don’t know about this amp. 

@Pharmaboy and @jonathan c both have other tube amps and can speak more intelligently than myself about how it compares. I can say this…

I have one of the world’s rarest and best SS amps and the HP8 holds its own.


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## Pharmaboy (Oct 23, 2022)

realmassy said:


> How’s the amp in terms of quietness? I tend to like solid state amps because I prefer a fast and clean sound, but also because I ‘hate’ hiss and noise in the headphones. The other tube amp I use (the Manley Absolute) sounds great in linear mode but shows some background noise in triode mode. It’s also a fantastic match for my low impedance Meze Empyreans, not so match with the HD800s and ZMF Atrium.
> Do you notice any noise on high impedance cans?


The Manley Absolute has more features and tricks than the HP8, for sure.

Then again, I've never heard any kind of noise from the HP8--zero noise with any headphone from ~25 ohms to 300 ohms impedance, and at any of the 3 impedance settings. The background stays black as night at all volume levels

I don't have IEMs so can't comment on that.

I'm not sure the HP8 is the best choice for low impedance planars. I had the Empyrean a few years back but no longer have it to check. I've used my Final D8000 & ZMF Ori (the latter a power hog) on the HP8, and there's plenty of power for both. I like the sound better for each with a powerful solid state amp, but that's hardly a knock on the HP8...just a planar fact of life.

Then again, I'm getting the best sound on my silkwood VO with the HP8, out of the 8 amps I have on hand. The bass is just nuts with the HP8, easily bettering any other tube amp I've heard (I owned a Woo WA22, big, heavy and powerful--but HP8 bass is better). 

I get a subtly different sound out of the OTL Woo WA3 on the VO. Still very nice, but not quite as authoritative as on the HP8. OTLs and TC-tube amps do things differently, so this isn't a knock on either amp.


----------



## realmassy

Thanks both for your messages, and thanks for confirming the amp is quiet. I plan to keep the Manley for the Meze, so it’s not a big deal if the HP8 doesn’t sound as good and authoritative with them. And there’s always my Fluxlab FA-12 solid state for the everyday use, it sounds fine with anything.
I’d say I’m pretty settled on the HP-8: it has a good form factor, seems to be a good match with high impedance headphones and it’s cheaper than most other amps I looked at. I can’t see myself committing to a 300b amp.
Will let you know once it’s with me, it might be in the next couple of weeks


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## WorksUnit

Rather nice that you don`t have to deal directly with Icon for service and upgrades in the UK.
Here is the first one I found: http://www.essexamprepairs.co.uk/


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## realmassy

Speaking of 300b, has anyone heard the new HP205D?


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## geoffalter11

realmassy said:


> Thanks both for your messages, and thanks for confirming the amp is quiet. I plan to keep the Manley for the Meze, so it’s not a big deal if the HP8 doesn’t sound as good and authoritative with them. And there’s always my Fluxlab FA-12 solid state for the everyday use, it sounds fine with anything.
> I’d say I’m pretty settled on the HP-8: it has a good form factor, seems to be a good match with high impedance headphones and it’s cheaper than most other amps I looked at. I can’t see myself committing to a 300b amp.
> Will let you know once it’s with me, it might be in the next couple of weeks


The HP8 sounded sublime with the Elite. Can’t wait to hear your impressions and a comparison to the Manley, which is considered one of the best tube amps on the market.

My LCD-4z sounds amazing on the HP8. I like it on the middle impedance setting for most everything. I use the high for the Atrium and Auteur but it doesn’t need it. I use my DAC to control the volume and voltage into the HP8.

I think for the price of $2k for the signature you will find it to be a great amp. The sound far outweighs the price. And Warren Lavender provides great service.


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## geoffalter11

realmassy said:


> Speaking of 300b, has anyone heard the new HP205D?


I’d love to hear that amp. The 205D is a ridiculous tube to find. The oldest tube made for electronics as I understand it. My guess knowing how the HP8 is that it sounds incredible. David Shaw is a seriously talented Amp Designer.


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## Toonartist

I've been looking at either the HP8 mkii or the 205d to partner up with the Naim Atom HE (as a preamp) for my Meze Elite. I dropped an email to Icon Audio about the 205d tubes and whether the amp will take the standard 300b tubes. They replied as follows:-

"Yes, the HP205D headphone amplifier can take the 205D or the 300B. When we were designing this amplifier we wanted to use a good quality pure triode valve and chose the 205D as it gets a lot of good reviews, understanding that the 205D can be hard to find or quite expensive, so we designed it to be able to use the 300B also and still give that excellent pure triode sound."

I've since asked them specifically about the Elrog 300b tubes and sent them a link to a page that contained a data sheet for them. Just waiting for a reply about that.

If they say that the Elrog tubes will work fine with the amp, then I could be tempted by the 205d with the 274b rectifier tube. I'm going to pop over to my local dealer on Wednesday to listen to the HP8 mkii though. They don't have the 205d in stock but should give me an idea of the quality / performance of their amps with my setup.


----------



## geoffalter11

Toonartist said:


> I've been looking at either the HP8 mkii or the 205d to partner up with the Naim Atom HE (as a preamp) for my Meze Elite. I dropped an email to Icon Audio about the 205d tubes and whether the amp will take the standard 300b tubes. They replied as follows:-
> 
> "Yes, the HP205D headphone amplifier can take the 205D or the 300B. When we were designing this amplifier we wanted to use a good quality pure triode valve and chose the 205D as it gets a lot of good reviews, understanding that the 205D can be hard to find or quite expensive, so we designed it to be able to use the 300B also and still give that excellent pure triode sound."
> 
> ...


I am sure that would make for a great pairing. At $1500 per Elrog it becomes an $8k amp. I would imagine that it will sound sensational knowing the Elrog is the 300b de jour.


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## Toonartist (Oct 24, 2022)

I'll be running with the 205d's to begin with but it would be nice to know that I have the option to run 300b Elrogs in the future! I know Elrog also do a 274b. We'll see what they say but I'm keen to listen to the HP8 Mkii though!


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## Toonartist

Ok... Icon came back to me about the Elrog 300b tubes and clarification ion the dimensions of the main part of the amp.

"We have checked the specifications of the Elrog 300B and it should be fine in the 205D headphone amplifier.

You are right about the dimensions, the ones given are for the power supply section. The measurements for the amplifier section are 22cms wide x 32cms deep (allow for inter-connects) x 21cms high for 205D and approximately 24cms high for 300B (depends on the height of the 300B)."


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## jonathan c

_Special _munitions for HP8…


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## Pharmaboy

jonathan c said:


> _Special _munitions for HP8…


Well, it is rotary...


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## RobertSM (Oct 24, 2022)

Fantastic tube for the HP8! When I owned the HP8 I ran a very similar Mazda. Classic European tuning , very balanced top to bottom with a high-end that seems like it comes from angles singing. One of the best top ends in all of my Hi-Fi experiences!  Enjoy.


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## jonathan c

RobertSM said:


> Fantastic tube for the HP8! When I owned the HP8 I ran a very similar Mazda. Classic European tuning , very balanced top to bottom with a high-end that seems like it comes from angles singing. One of the best top ends in all of my Hi-Fi experiences!  Enjoy.


Plus, the HP8 uses only one at a time 😀🤪👍.


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## Toonartist (Oct 24, 2022)

Secretly, I'm hoping to be so bowled over with the demo of the HP8 mkii on Wednesday that I'll not even feel the need for the 205d 

I love the Naim Atom HE as a solid state option for sound and features. I'm a sucker for great soundstage and imaging and I guess this is one of the key things I'm looking for. I want to feel the music around me, even more than the HE does.


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## jonathan c

Pharmaboy said:


> Well, it is rotary...


at least the triple micas are…🤩


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## jonathan c

Toonartist said:


> Secretly, I'm hoping to be so bowled over with the demo of the HP8 mkii on Wednesday that I'll not even feel the need for the 205d
> 
> I love the Naim Atom HE as a solid state option for sound and features. I'm a sucker for great soundstage and imaging and I guess this is one of the key things I'm looking for. I want to feel the music around me, even more than the HE does.


What headphone(s) will you bring to the demo? And, note the tubes that are used in HP8 for the demo.


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## geoffalter11

Toonartist said:


> Secretly, I'm hoping to be so bowled over with the demo of the HP8 mkii on Wednesday that I'll not even feel the need for the 205d
> 
> I love the Naim Atom HE as a solid state option for sound and features. I'm a sucker for great soundstage and imaging and I guess this is one of the key things I'm looking for. I want to feel the music around me, even more than the HE does.


HP8 will surprise you. It is such a wonderful amp.


Toonartist said:


> Secretly, I'm hoping to be so bowled over with the demo of the HP8 mkii on Wednesday that I'll not even feel the need for the 205d
> 
> I love the Naim Atom HE as a solid state option for sound and features. I'm a sucker for great soundstage and imaging and I guess this is one of the key things I'm looking for. I want to feel the music around me, even more than the HE does.


----------



## Toonartist

jonathan c said:


> What headphone(s) will you bring to the demo? And, note the tubes that are used in HP8 for the demo.


I’ll be taking my Meze Elite + Lavricables Grand cable. They have a Naim Atom HE so they’re going to set it up as the preamp/source.


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## geoffalter11

Toonartist said:


> I’ll be taking my Meze Elite + Lavricables Grand cable. They have a Naim Atom HE so they’re going to set it up as the preamp/source.


Enjoy! Sounds like a great listen. I recommend using the Medium impedance.


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## Toonartist

Well, just back from listening to the HP8 mkii. It's an impressive little amp. It was the standard version. 

What surprised me most is how tube like the Naim Atom HE sounded. There were a lot of similarities in terms of the tonality of the two amps. The HP8 was slightly smoother and wider but the Naim HE had better detail, depth, pace and dynamics. It just felt faster and more agile, which I guess it should do being a solid state amp. What difference does the cap upgrade make to the sound?

The Naim HE was the better amp overall but I enjoyed the smoothness of the HP8. The Sennheiser 800s sounded very nice with it. 

Other positives with the HP8... bass, really digs deep! Very impressed with that and, how quiet it is. Zero hum / hiss etc when using the Naim HE as the preamp. Worked flawlessly. It was the perfect size to sit next to the Naim HE on one shelf. I'd say the HP8 mkii offers excellent value for money to be honest, seems to punch well above it's asking price!


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## realmassy

Thanks for the impressions @Toonartist . I think you mentioned the new 205D wasn't available for demo, right?


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## Toonartist

Correct. Unfortunately that wasn't an option to demo. I think as a partner to the Naim HE, the 205D would probably make more sense as it is likely to offer a step up in terms of performance. 

When I came back from listening to the HP8 mkii, someone said on the Naim HE thread that it sounded more like a tube amp than a solid state, and now having listened to a tube amp I have to agree. It has the slightly warmer bass / mids but with very good detail and pace. I was impressed with the HD800s for classical through both the HE and HP8 mkii but, I'd imagine they wouldn't be as versatile as the Elites. DCA Expanse & Stealths are also in the mix as alternatives.

 I'm going to sit back and think it over... amp or headphones to provide an alternative


----------



## jonathan c

Toonartist said:


> Well, just back from listening to the HP8 mkii. It's an impressive little amp. It was the standard version.
> 
> What surprised me most is how tube like the Naim Atom HE sounded. There were a lot of similarities in terms of the tonality of the two amps. The HP8 was slightly smoother and wider but the Naim HE had better detail, depth, pace and dynamics. It just felt faster and more agile, which I guess it should do being a solid state amp. What difference does the cap upgrade make to the sound?
> 
> ...


I cannot say what the ‘standard’ HP8 sounds like. I will say that the ‘signature’ version - with Mundorf capacitors, Mullard gold pin 6201, pair of RCA ‘narrow gap plate’ 6SN7 - is _agile_ indeed: with gravitas, heft, PRaT!


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## Toonartist

Well, the upgraded version + a pair of brand new HD800s headphones would be about the same prices as the 205d with Mundorf Caps. I'll have a spell to think over the options.

One thing that I was certain about... I didn't like the HD820 at all. They just sounded weird to me.


----------



## Toonartist

Just looked back over the email from Icon about the HP8, - "HP8 MkII with Mundorf caps and white base CV181 and gold pin 12AX7 £1299.95"

The one I listened too definitely had brown base to the tubes so it wasn't the signature version. It would be great to hear from anyone who has heard or gone from standard to upgraded version and how much difference it makes!


----------



## jonathan c

Toonartist said:


> Just looked back over the email from Icon about the HP8, - "HP8 MkII with Mundorf caps and white base CV181 and gold pin 12AX7 £1299.95"
> 
> The one I listened too definitely had brown base to the tubes so it wasn't the signature version. It would be great to hear from anyone who has heard or gone from standard to upgraded version and how much difference it makes!


On Head-Fi, there are not many owners of HP8, standard or signature. It may take quite a while for an owner who has walked the upgrade path to surface. 🤷🏻‍♂️


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## Toonartist

Very true… the lack of activity and talk anywhere on the internet about the 205d is putting me off that amp for it a a gamble nd a reasonable chunk of cash. The rectifier tubes Cayin use is putting me off them. Very rare and you need between 2-4 of them depending which amp you go for. I guess that leaves Auris and Feliks in the UK for higher end stuff and some of Feliks amps are not suited to planar headphones!


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## geoffalter11

I started with a regular MK2. It arrived and didn’t work. They forgot to change the fuses snd voltage and immediately blew out the fuses day one. When I sent back to be corrected I had the upgrade done. It came back working as a signature. The broker told me the difference between the two was warmth and less top end resolution. The Mundorfs and Ceramics took away the warmth, and added a bit of resolution.


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## geoffalter11

I am probably the closest to being able to tell you the difference, because I actually bought the regular. But I never got to actually listen to it as I upgraded when they fixed it.

Warren Lavender felt the regular version was really good, but the signature would provide better resolution. Wish I could give better impressions between the two. I did my upgrade at that time as they were about to take a big price jump. Not sure what $1299 Euro equates to, but they are selling the Signature for $2k on Audiogon now.


----------



## jonathan c

Toonartist said:


> Very true… the lack of activity and talk anywhere on the internet about the 205d is putting me off that amp for it a a gamble nd a reasonable chunk of cash. The rectifier tubes Cayin use is putting me off them. Very rare and you need between 2-4 of them depending which amp you go for. I guess that leaves Auris and Feliks in the UK for higher end stuff and some of Feliks amps are not suited to planar headphones!


The WE 205 tubes are very hard to find. If one uses Elrog 300 tubes etc in their place, that is 💪 and 🦵….. 😲. As for Cayin, the choice of 22DE4 rectifier tubes was enough for me to follow the advice of Dionne Warwick: “walk on by”…🚶


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## jonathan c (Oct 27, 2022)

geoffalter11 said:


> I am probably the closest to being able to tell you the difference, because I actually bought the regular. But I never got to actually listen to it as I upgraded when they fixed it.
> 
> Warren Lavender felt the regular version was really good, but the signature would provide better resolution. Wish I could give better impressions between the two. I did my upgrade at that time as they were about to take a big price jump. Not sure what $1299 Euro equates to, but they are selling the Signature for $2k on Audiogon now.


USD and EUR are basically at parity (1:1). CAD = 0.7393 USD.


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## realmassy

jonathan c said:


> The WE 205 tubes are very hard to find. If one uses Elrog 300 tubes etc in their place, that is 💪 and 🦵….. 😲. As for Cayin, the choice of 22DE4 rectifier tubes was enough for me to follow the advice of Dionne Warwick: “walk on by”…🚶


What is the problem with that rectifier?


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## jonathan c (Oct 27, 2022)

realmassy said:


> What is the problem with that rectifier?


It may be electrically/sonically fine…but it is certainly not as common as one in, say, the 5U4G category. Most rectifiers run on 5v; some, on 4v. The 22DE4?….22v !! Note the use within b&w televisions: nothing to do with power supply rectification or regulation. Note the use of the 5U4GB.


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## realmassy

Got it, so it's mainly an issue of finding alternatives/replacements...fair enough


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## jonathan c (Oct 27, 2022)

geoffalter11 said:


> I am probably the closest to being able to tell you the difference, because I actually bought the regular. But I never got to actually listen to it as I upgraded when they fixed it. Warren Lavender felt the regular version was really good, but the signature would provide better resolution. Wish I could give better impressions between the two. I did my upgrade at that time as they were about to take a big price jump. Not sure what $1299 Euro equates to, but they are selling the Signature for $2k on Audiogon now.**



** Do you mean Audioarcan?  Also, the Signature _sans _Bluetooth was, for me, $1865 USD two months ago.


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## geoffalter11

jonathan c said:


> ** Do you mean Audioarcan?  Also, the Signature _sans _Bluetooth was, for me, $1865 USD two months ago.


Yes. They advertise $1995 on Audiogon. I bought in February at $1600 for signature.


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## Pharmaboy

jonathan c said:


> The WE 205 tubes are very hard to find. If one uses Elrog 300 tubes etc in their place, that is 💪 and 🦵….. 😲. As for Cayin, the choice of 22DE4 rectifier tubes was enough for me to follow the advice of Dionne Warwick: “walk on by”…🚶


I make a point of following Dionne Warwick's advice...


----------



## Pharmaboy (Oct 27, 2022)

My HP8 was sold by (I believe) the 3rd owner, a Canadian fellow. It had come to him as a stock HP8, not signature. He paid a local audio tech to swap out the caps for Mundorfs (showed me email correspondence & receipt--it wasn't cheap). The power tubes were the stock's brown base CV-181s and the driver was a Gold Lion 12AX7 the seller had installed in place of the stock JJ that he said sounded inferior. I bought the amp w/those tubes for ~$835 USD. Even though I got bent over by Paypal (transaction fee is nearly 3% now, plus they subtract another ~5% in bogus currency conversion fees, effectively changing USD to CAD at a rate far below bank rates), I thought that was a pretty fair price, especially once I got the HP8 in my hands and could feel/see its quality

As for tubes, I ended up rolling them, so the tubes it came with no longer mattered. Even with those tubes, the sound was strikingly good, better than most tube amps I've heard: very clear, black background, zero noise or distortion, dynamic, exceptional bass, zero wooliness or excessive warmth, but still with that wonderful 3D quality & spatial expansiveness TC-tube amps have.

After rolling in NOS '50s RCA 6SN7s, I tried a number of older NOS driver tubes; all work well, and each has subtly different sonics that distinguish it. I concluded that while the HP8 is hardly one of those amps whose stock tubes are bad, forcing you to roll in $1000+ of NOS tubes to simply sound OK--its sound does clearly scale with selective tube rolling.

The amp is also compact (by TC-tube amp standards) and quite handsome. The copper plate on the front section looks amazing. All in all, I think I got a LOT of good sound for relatively little $$.


----------



## paradoxper

Toonartist said:


> Very true… the lack of activity and talk anywhere on the internet about the 205d is putting me off that amp for it a a gamble nd a reasonable chunk of cash. The rectifier tubes Cayin use is putting me off them. Very rare and you need between 2-4 of them depending which amp you go for. I guess that leaves Auris and Feliks in the UK for higher end stuff and some of Feliks amps are not suited to planar headphones!


Go with Envy or Telemachus. More importantly, go with Elrog.


----------



## Toonartist (Oct 28, 2022)

paradoxper said:


> Go with Envy or Telemachus. More importantly, go with Elrog.


I had the Envy ordered but they mucked me around no end. I gave in after about 4 months. I might consider it again but I've been looking at the Mcintosh MHA200 as well as a couple of others for my tube hit.

Edit. the Telemachus has a rather nice industrial look to it! Thanks


----------



## Toonartist

Pharmaboy said:


> My HP8 was sold by (I believe) the 3rd owner, a Canadian fellow. It had come to him as a stock HP8, not signature. He paid a local audio tech to swap out the caps for Mundorfs (showed me email correspondence & receipt--it wasn't cheap). The power tubes were the stock's brown base CV-181s and the driver was a Gold Lion 12AX7 the seller had installed in place of the stock JJ that he said sounded inferior. I bought the amp w/those tubes for ~$835 USD. Even though I got bent over by Paypal (transaction fee is nearly 3% now, plus they subtract another ~5% in bogus currency conversion fees, effectively changing USD to CAD at a rate far below bank rates), I thought that was a pretty fair price, especially once I got the HP8 in my hands and could feel/see its quality
> 
> As for tubes, I ended up rolling them, so the tubes it came with no longer mattered. Even with those tubes, the sound was strikingly good, better than most tube amps I've heard: *very clear, black background, zero noise or distortion, dynamic, exceptional bass, zero wooliness or excessive warmth, but still with that wonderful 3D quality & spatial expansiveness TC-tube amps have.*
> 
> ...


From my 3hr spell with it I'd agree with that. I was impressed by how deep the bass was and that it was near black quiet. It also made me think about how much space I want a tube amp to take up. It sits really well with the Naim HE on one shelf. It's one reason I've also been considering the Mcintosh MHA200.


----------



## geoffalter11

Toonartist said:


> From my 3hr spell with it I'd agree with that. I was impressed by how deep the bass was and that it was near black quiet. It also made me think about how much space I want a tube amp to take up. It sits really well with the Naim HE on one shelf. It's one reason I've also been considering the Mcintosh MHA200.


I borrowed the mha200 for 2 months and ran them side by side. The HP8 was the better amp for my preferences. The MHA200 was quite good, just doesn’t have the same note weight or physicality in the sound. But it was very fast and transparent with a beautiful image. Bass felt anemic in comparison. I also didn’t love the unity gain philosophy. No volume at 11, basic Lowe volume at 12, ear splitting volume by 2 on the pot:

It’s a beautiful amp, no doubt.


----------



## Toonartist

Certainly food for thought!

I'll not be using the volume control on either unit. It will be set and forget with control coming via the Naim HE. I certainly value soundstage and imaging but I also don't want an amp to sound thin either. My local deal sells the MHA200 but I'm not sure if he has them in as a demo unit. That said, I know in the past they've just said take it, if you don't like it bring it back. It maybe an option.

What I find reassuring now is I do have a good baseline to work from with the standard HP8 mkii.


----------



## jonathan c

With a pair of RCA ‘narrow gap’ plate 6SN7 + Raytheon CK 5751, the HP8 / Sennheiser HD6XX _is_ 🎼 🎵 🎶…


----------



## geoffalter11

I'm rocking my Raytheon VT-231s with the same Raytheon CK 5751, HP8 and my LCD-4z.

Bliss!  I love this amp!


----------



## AnalogEuphoria

JonT said:


> For 2 years - since I've had it - I used only the stock tubes supplied with my SE: Shuguang Black Treasure CV181s and an EH 12AX7 gold pin.
> 
> Source is vinyl only: Technics SL1200G - Dynavector DV XX2 Mk2 - Cyrus Phono Signature/PSX R2 Power Supply into HD800S.
> 
> ...



I had the same experience when I rolled in some gold lions on a Valhalla 2, harsh grainy sound, not very pleasant at all.


----------



## Jay Smith

I wonder if HP8 can drive Hifiman HE6se V2 well please help.


----------



## JonT

Jay Smith said:


> I wonder if HP8 can drive Hifiman HE6se V2 well please help.



Full disclosure - I haven't heard this combination.

That said, the the 3 setting multi-tap transformer on the HP8 puts out 27v or 34db gain on High, 15v or 31db gain on Medium, 9v or 21db on Low. I see you own the HP8Mk2, so I guess you know this.

I can't imagine the HP8 will have any problems driving the modest impedance HE6s with authority and to high volume, despite their low sensitivity.


----------



## Jay Smith

JonT said:


> Full disclosure - I haven't heard this combination.
> 
> That said, the the 3 setting multi-tap transformer on the HP8 puts out 27v or 34db gain on High, 15v or 31db gain on Medium, 9v or 21db on Low. I see you own the HP8Mk2, so I guess you know this.
> 
> I can't imagine the HP8 will have any problems driving the modest impedance HE6s with authority and to high volume, despite their low sensitivity.


Thank you! I might give it a try of HE6se V2.  HP8mk2 give very good result on my Clear and I have faith.


----------



## -Darkstar-

Considering the Icon only has 800 mW peak power, I would expect you'd find the sound fairly soft with the HE6se V2. You should probably find something with at least 3wpc for those cans, if not more.


----------



## Jay Smith

-Darkstar- said:


> Considering the Icon only has 800 mW peak power, I would expect you'd find the sound fairly soft with the HE6se V2. You should probably find something with at least 3wpc for those cans, if not more.


Thank you! Factory recommend 2W minimum indeed.


----------



## JonT

When Hifi World measured the HP8 Mk2 in 2016 - see below - they claimed a power/use case for all situations (but perhaps the HE6se was not in their thinking).


----------



## Jay Smith

JonT said:


> When Hifi World measured the HP8 Mk2 in 2016 - see below - they claimed a power/use case for all situations (but perhaps the HE6se was not in their thinking).


Yes Sir I read that issue also.  Love the sound of HP8 on T1 and Clear. really want to try HE6se because I only use 9 o'clock volume on T1(mid gain) and Clear(Low gain) 10 o'clock volume is very very loud.  Seems plenty of juice left.


----------



## Pharmaboy (Dec 28, 2022)

Jay Smith said:


> I wonder if HP8 can drive Hifiman HE6se V2 well please help.


I've never managed to hear this headphone, though I understand it's among the legendary few (such as the Abyss, Hifiman Susvara, a few others) that routinely bring amps to their knees. It's also a planar, which matters a lot in this context.

I find the HP8 to be (in practical use) one of the more powerful tube amps I've ever heard. It's wonderful with all my dynamic driver headphones, including the 300 ohm ones. But that doesn't mean it's the ideal choice for inefficient planars like the HE6se V2.

I've heard my Final D8000 planar (60 ohm, relatively efficient) on the HP8; also my ZMF Ori planar (very inefficient, a power hog). There's plenty of volume for both. But the HP8 doesn't really drive that great planar bass as well as strong SS amps can.

To be clear--there are a number of larger, more expensive, higher tube count transformer-coupled tube amps that many here use with success on even the most challenging headphones. But IMO you really have to spend money on those amps (and the many NOS tubes to roll in them) to get to the same place a strong SS amp will get you.


----------



## Jay Smith

Pharmaboy said:


> I've never managed to hear this headphone, though I understand it's among the legendary few (such as the Abyss, Hifiman Susvara, a few others) that routinely bring amps to their knees. It's also a planar, which matters a lot in this context.
> 
> I find the HP8 to be (in practical use) one of the more powerful tube amps I've ever heard. It's wonderful with all my dynamic driver headphones, including the 300 ohm ones. But that doesn't mean it's the ideal choice for inefficient planars like the HE6se V2.
> 
> ...


Thank you for your advise.  I guess don't be greedy this time.


----------



## geoffalter11 (Dec 28, 2022)

Peter is right. The Icon is fantastic in all ways but two.

1. It doesn’t have the same control over power hungry Planars like SS or high powered SET tube amps.
2. Top end resolution is good not great.  But, this is something reserved for only the best SS amps or tube amps on the market.

Otherwise, the HP8 is about as good an amp as you will find. At its price point there are very few competitors in my opinion.

My 4z does great with the HP8 but it is a very efficient headphone and my Radiante and OG sing beautiful songs on the HP8. Perfect synergy.


----------



## -Darkstar-

Jay Smith said:


> Thank you! Factory recommend 2W minimum indeed.


Based on comments from HE6 people, I'd look for an amp with around 6wpc. There are some people that run them off a stereo amp instead of a headphone amp.


----------



## jonathan c

@Pharmaboy and @geoffalter11 have expressed well the _many _virtues / _few_ shortcomings of Icon Audio HP8. My experiences with HP8 match theirs: it is _unworldly synergistic _with all ZMF dynamic headphones (300 ohms) - from Aeolus to Verite. Below, with Verite Open 🥲:

  [Tubes are RCA ‘narrow gap plate’ 6SN7 pair, Raytheon 5751 ‘windmill getter’.]


----------



## geoffalter11

-Darkstar- said:


> Based on comments from HE6 people, I'd look for an amp with around 6wpc. There are some people that run them off a stereo amp instead of a headphone amp.


I don’t think the HE6 needs 6 watts. Provided it has the right gain and slew rate it can sing with a watt. My Spring 1 drives it beautifully and has a written 153mw into 62 ohm with 25 db of gain. The HE6 never went above 10 on the volume dial. Same for the Susvara.


----------



## geoffalter11

jonathan c said:


> @Pharmaboy and @geoffalter11 have expressed well the _many _virtues / _few_ shortcomings of Icon Audio HP8. My experiences with HP8 match theirs: it is _unworldly synergistic _with all ZMF dynamic headphones (300 ohms) - from Aeolus to Verite. Below, with Verite Open 🥲:  [Tubes are RCA ‘narrow gap plate’ 6SN7 pair, Raytheon 5751 ‘windmill getter’.]


That is a beautiful set up Verite's and one sexy set up.


----------



## jonathan c

Thank you! There’s the _gestalt _to the reproduction of music via HP8 Signature: it brings me back from other headphone amplifiers …(_as a moth to a light? 😳😀)_


----------



## JerseyD

jonathan c said:


> @Pharmaboy and @geoffalter11 have expressed well the _many _virtues / _few_ shortcomings of Icon Audio HP8. My experiences with HP8 match theirs: it is _unworldly synergistic _with all ZMF dynamic headphones (300 ohms) - from Aeolus to Verite. Below, with Verite Open 🥲:  [Tubes are RCA ‘narrow gap plate’ 6SN7 pair, Raytheon 5751 ‘windmill getter’.]



I’m a few days away from firing up my new HP8 Sig.  Is the High output setting the preferred one for ZMFs?


----------



## jonathan c

JerseyD said:


> I’m a few days away from firing up my new HP8 Sig.  Is the High output setting the preferred one for ZMFs?


The H-M-L knob to the right is an impedance loading switch. ‘High’ would be the one for ZMF dynamic headphones - which have a nominal impedance of 300 ohms.


----------



## geoffalter11

Listening to my Spirit Torino Radiante 1706 with HP8 MK2 Signature tonight.  Raytheon 6SN7GTs and a Amperex 'Fisher' 12AX7.  Delightful.  I have spent so much time with ZMF headphones as of late it is nice to listen to my favorite closed back headphone on my favorite tube amp.  What a great combo.  So musical, open, and aggressive while still being extremely subtle.  The HP8 is a master at creating a holographic stage with impeccable tone and the best bottom end in the biz... It is an extremely muscular amp while possessing a gentile and subtle midrange.  Such an awesome amp!  I was told that I was leaving sound on the table by having an HP8.  I disagree wholeheartedly.  It doesn't resolve like a Nirvana or an Envy or Stellaris, but that is fine by me.


----------



## jonathan c

geoffalter11 said:


> Listening to my Spirit Torino Radiante 1706 with HP8 MK2 Signature tonight.  Raytheon 6SN7GTs and a Amperex 'Fisher' 12AX7.  Delightful.  I have spent so much time with ZMF headphones as of late it is nice to listen to my favorite closed back headphone on my favorite tube amp.  What a great combo.  So musical, open, and aggressive while still being extremely subtle.  The HP8 is a master at creating a holographic stage with impeccable tone and the best bottom end in the biz^^.. It is an extremely muscular amp while possessing a gentile and subtle midrange.  Such an awesome amp!  I was told that I was leaving sound on the table by having an HP8.  I disagree wholeheartedly.  It doesn't resolve like a Nirvana or an Envy or Stellaris, but that is fine by me**


^^ other than your spouse! 😂
**  without the context of Pace, Rhythm & Timing, and tonal balance, resolution itself would be a maddening distraction.


----------



## geoffalter11

jonathan c said:


> ^^ other than your spouse! 😂
> **  without the context of Pace, Rhythm & Timing, and tonal balance, resolution itself would be a maddening distraction.


Agreed... PRAT is where its AT!!!!


----------



## JerseyD

Finally beginning to listen to (and burn in) the HP8 MkII Signature (with stock Psvane "David Shaw" CV181's and Gold Lion ECC83).  Paired with brand new Auteur Classic - so a lot of burn in to do for both!  Listening as I go.  Nice heft to the sound so far.  A bit brighter than I expected the pairing to be, but that may very well calm down after more hours of usage.  Warren at Audioarcan said "the Mundorf capacitors take a minimum of 15 - 20 hours to burn in," so I'm not jumping to any conclusions.  Of course, I'm already smiling while I listen, so any improvement from here is icing on the cake.


----------



## geoffalter11

JerseyD said:


> Finally beginning to listen to (and burn in) the HP8 MkII Signature (with stock Psvane "David Shaw" CV181's and Gold Lion ECC83).  Paired with brand new Auteur Classic - so a lot of burn in to do for both!  Listening as I go.  Nice heft to the sound so far.  A bit brighter than I expected the pairing to be, but that may very well calm down after more hours of usage.  Warren at Audioarcan said "the Mundorf capacitors take a minimum of 15 - 20 hours to burn in," so I'm not jumping to any conclusions.  Of course, I'm already smiling while I listen, so any improvement from here is icing on the cake.


Congrats on your HP8 MK2 Signature. Welcome to the family and the wonderful world of the Icon HP8. It is a truly special amp. It will definitely change a bit between 50-100 hrs. Warren is right, the caps and transformers take 25 hrs or so. The tubes take a bit longer. Tube rolling with the HP8 can also be fun. The changes aren’t significant, but differences there are. One of the best ways to manage the amps gain is to use a 12AT7 NOS tube which will give you a bit more volume play and better dynamic range. 12AT7s are also 1/3 of the price of 12AX7 NOS tubes.

I have had great luck with the following tubes…

6SN7 Variants - RCA 1950s and 1960s. Raytheon 6SN7GTs, any of the VT-231s.

12AX7/12AT7s - Brimar, RCA, Amperex, RFT, Telefunken, Raytheon, 5751 variants which are 70db instead of 100db with the 12AX7. The 12AT7 is 60db.

David Shaw will say that he can’t hear a difference with tube rolling. But, he has also told me that differences will lie within the tolerances of the tubes. More flavor than SQ. So, YMMV. I went 4 months with the Ceramics and the 12AX7EH that the amp shipped with before I began to roll tubes. I loved it with its upgraded stock tube package as well. I found the CV181s to be a smidge microphonic which is why I tried other tubes.


----------



## Pharmaboy

geoffalter11 said:


> David Shaw will say that he can’t hear a difference with tube rolling.


That tickles my funny bone. It's paradoxical, not what you'd expect ... a bit like the fact that good musicians often have s**t stereos.


----------



## geoffalter11

All of what I have learned about tubes comes from @jonathan c . He is a wealth of knowledge and has helped me to increase my level enjoyment with the HP8 exponentially.


----------



## geoffalter11

Pharmaboy said:


> That tickles my funny bone. It's paradoxical, not what you'd expect ... a bit like the fact that good musicians often have s**t stereos.


I like to read about my favorite guitar players and what tubes they like in their amps.


----------



## JonT

JerseyD said:


> Finally beginning to listen to (and burn in) the HP8 MkII Signature (with stock Psvane "David Shaw" CV181's and Gold Lion ECC83).  Paired with brand new Auteur Classic - so a lot of burn in to do for both!  Listening as I go.  Nice heft to the sound so far.  A bit brighter than I expected the pairing to be, but that may very well calm down after more hours of usage.  Warren at Audioarcan said "the Mundorf capacitors take a minimum of 15 - 20 hours to burn in," so I'm not jumping to any conclusions.  Of course, I'm already smiling while I listen, so any improvement from here is icing on the cake.


Welcome to the HP8MkII club! Notwithstanding burn in, when I swapped out the EH 12AX7 Gold Pin that shipped with my Signature Edition for a Gold Lion the sound became very, very bright (and not my cup of tea) - I swapped back in the EH and tonal balance was restored. I'm one of David Shaw's loyal customers - but one who disagrees with him on the extent of tonal shift that tube rolling potentially brings to the HP8.

(Of which, I've done far, far, far less than the other members above - but I did also experiment with some NOS Brimar 12AX7 and 12AT7s sourced from Langrex here in the UK, pleasing in effect but to my ears not necessarily better than the new production EH I started with).


----------



## The Jester

Haven’t had the urge to change my signature edition either, with Quad ERA-1 it has a similar tonal balance as my 2 channel system I spent many hours (years 🙄) getting “just right” for my ears/tastes ….
I’ve found in the past that’s it’s all too easy in the search for “bigger, better, faster, more” that it’s all too easy to lose the magic or synergy of a well tuned system.
“If in doubt, do nothing “ .. 😃


----------



## WorksUnit

Glued to the Clear OG, Denafrips Aries2. David Shaw CV181, with a pretty basic Mullard for a couple of months.
Looking forward to getting it serviced, and experimenting with some of the tube suggestion:s


----------



## jonathan c (Jan 5, 2023)

geoffalter11 said:


> All of what I have learned about tubes comes from @jonathan c . He is a wealth of knowledge** and has helped me to increase my level enjoyment with the HP8 exponentially.


** I’ll say again _because they deserve the ongoing acknowledgment:_ without the generous advice (guidance, humour, ribbing) from Head-Fiers such as @bcowen, @Paladin79, @Ripper2860, @RobertSM, @L0rdGwyn, @Galapac, @Pharmaboy, @mordy, @gibosi, @UntilThen …..

I’d be:   a tube in a socket, with a rube’s empty pocket.


----------



## jonathan c

geoffalter11 said:


> I like to read about my favorite guitar players and what tubes they like in their amps.


🤪 I like to ask my amps’ tubes what their favourite music is to pass through…😳


----------



## geoffalter11

jonathan c said:


> 🤪 I like to ask my amps’ tubes what their favourite music is to pass through…😳


Do they answer?  I would like to know what they say.


----------



## geoffalter11

jonathan c said:


> ** I’ll say again _because they deserve the ongoing acknowledgment:_ without the generous advice (guidance, humour, ribbing) from Head-Fiers such as @bcowen, @Paladin79, @Ripper2860, @RobertSM, @L0rdGwyn, @Galapac, @Pharmaboy, @mordy, @gibosi, @UntilThen …..
> 
> I’d be:   a tube in a socket, with a rube’s empty pocket.


@Pharmaboy and @Paladin79 have also been amazing with me.  Great insights, positive vibes and tons of knowledge and intellect.  

Tonight the HP8 and Atrium are floating in a marshmallow sea.  RCA Narrow Gaps (6SN7GTB) with an RCA 12AX7A in the driver seat.  Sound is forceful, subtle, and ALIVE.


----------



## Paladin79

geoffalter11 said:


> @Pharmaboy and @Paladin79 have also been amazing with me.  Great insights, positive vibes and tons of knowledge and intellect.
> 
> Tonight the HP8 and Atrium are floating in a marshmallow sea.  RCA Narrow Gaps (6SN7GTB) with an RCA 12AX7A in the driver seat.  Sound is forceful, subtle, and ALIVE.


Thanks for the kind words, I am not familiar with the Icon amp mentioned in this thread but I will try to check one out sometime.


----------



## jonathan c

geoffalter11 said:


> Do they answer?  I would like to know what they say.


….anything but Ray Conniff Orchestra, Mantovani w/ Strings, Captain & Tennille….😀


----------



## Paladin79 (Jan 6, 2023)

Pharmaboy said:


> I've never managed to hear this headphone, though I understand it's among the legendary few (such as the Abyss, Hifiman Susvara, a few others) that routinely bring amps to their knees. It's also a planar, which matters a lot in this context.
> 
> I find the HP8 to be (in practical use) one of the more powerful tube amps I've ever heard. It's wonderful with all my dynamic driver headphones, including the 300 ohm ones. But that doesn't mean it's the ideal choice for inefficient planars like the HE6se V2.
> 
> ...


I suspect the Focal Utopias would do great, for me right at one watt is more than enough power on amps I designed.
 I recently started using a product that will turn most any power amp into a headphone amp so power is not an issue for me.
Finnegan is helping with the setup, this is a 15 watt per channel amp I designed, now a headphone amp as well as an amp to drive min-radial speakers similar to what Decware makes.


----------



## JerseyD

Paladin79 said:


> I recently started using a product that will turn most any power amp into a headphone amp so power is not an issue for me.


Now that sounds like an interesting product.  What is it?


----------



## Paladin79 (Jan 6, 2023)

JerseyD said:


> Now that sounds like an interesting product.  What is it?


I bought it from a friend, I believe it was made by Black Box, there is no model number on it whatsoever. I did find it online for about $450 or so, I will keep looking and see if I can post a link.



I bought a friends PrimaLuna amp and he used this instead of the built in headphone out. I went back and bought it later and began using it with a Cary tube amp as well as one I designed. All tube amps of course.


----------



## Paladin79 (Jan 6, 2023)

https://ampsandsound.com/products/black-box-headphone-adapter

A little cheaper than I recalled, Ampsandsound makes it, and I guess it is called a black box cause nothing is written on the box lol.


----------



## JerseyD

Paladin79 said:


> https://ampsandsound.com/products/black-box-headphone-adapter
> 
> A little cheaper than I recalled, Ampsandsound makes it, and I guess it is called a black box cause nothing is written on the box lol.


That is fascinating.  Can't say I have ever seen a speaker amp -to- headphone jack converter simply by hooking up the speaker cables and using the speaker amp's volume control.  I wonder how much power is passing through in relation to the speaker amp.  Can't imagine it's 100% but I guess it's possible!


----------



## Paladin79

JerseyD said:


> That is fascinating.  Can't say I have ever seen a speaker amp -to- headphone jack converter simply by hooking up the speaker cables and using the speaker amp's volume control.  I wonder how much power is passing through in relation to the speaker amp.  Can't imagine it's 100% but I guess it's possible!


It seems very possible lol, I know there is more power there than I would ever use with most of my headphone cables. I use a Freya + with my power amps, (PrimaLuna is integrated) so I am always careful about power levels when using this device. I will tell you though, I have a little hum with one amp that I can barely detect on a speaker, this device really lets you hear each channel.   Note the lack of instructions or info on the website lol.


----------



## Paladin79

JerseyD said:


> That is fascinating.  Can't say I have ever seen a speaker amp -to- headphone jack converter simply by hooking up the speaker cables and using the speaker amp's volume control.  I wonder how much power is passing through in relation to the speaker amp.  Can't imagine it's 100% but I guess it's possible!


In looking for some vu meters to add to a line level switch box I am making for a friend, I found a couple power meters that I will install in the 15 watt amp, in doing so I will make an attempt to compare power in and power out on the headphone adapter. Luckily I have a wooden front on the amp so meter installation should be fairly easy.


----------



## gimmeheadroom (Tuesday at 11:26 AM)

JerseyD said:


> That is fascinating.  Can't say I have ever seen a speaker amp -to- headphone jack converter simply by hooking up the speaker cables and using the speaker amp's volume control.  I wonder how much power is passing through in relation to the speaker amp.  Can't imagine it's 100% but I guess it's possible!



This is almost standard practice for the Hifiman HE6. Hifiman even sells a box for this, but people have said it sounds better just to go direct to the speaker taps and not use the converter box. I think it was originally included at no additional charge with the HE6, but it disappeared as HE6SE and V2 started coming out.

https://store.hifiman.com/index.php/he-adapter.html


----------



## Paladin79 (Tuesday at 11:50 AM)

gimmeheadroom said:


> This is almost standard practice for the Hifiman HE6. Hifiman even sells a box for this, but people have said it sounds better just to go direct to the speaker taps and not use the converter box. I think it was originally included at no additional charge with the HE6, but it disappeared as HE6SE and V2 started coming out.
> 
> https://store.hifiman.com/index.php/he-adapter.html


I looked inside the one I have and I could easily build such a thing. While pricey, mine uses a nice heavy cabinet and offers a quarter inch Jack as well as balanced out. Mine is currently hooked to a Cary amp.


----------



## gimmeheadroom

Paladin79 said:


> I looked inside the one I have and I could easily build such a thing. While pricey, mine uses a nice heavy cabinet and offers a quarter inch Jack as well as balanced out. Mine is currently hooked to a Cary amp.


That goes without saying, knowing you from your posts. You make beautiful stuff!


----------



## Paladin79 (Tuesday at 1:32 PM)

gimmeheadroom said:


> That goes without saying, knowing you from your posts. You make beautiful stuff!


Thanks, my camera angle sucks in that photo lol. All racks are perfectly level. I am finishing up a go cart for my cat, I may get to use it to hold albums as well.   Adding casters now.


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## gimmeheadroom

Paladin79 said:


> Thanks, my camera angle sucks in that photo lol. All racks are perfectly level. I am finishing up a go cart for my cat, I may get to use it to hold albums as well.   Adding casters now.



I know how it is. All my pics look like that, and it's not the camera's fault


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## Pharmaboy

gimmeheadroom said:


> This is almost standard practice for the Hifiman HE6. Hifiman even sells a box for this, but people have said it sounds better just to go direct to the speaker taps and not use the converter box. I think it was originally included at no additional charge with the HE6, but it disappeared as HE6SE and V2 started coming out.
> 
> https://store.hifiman.com/index.php/he-adapter.html


But I draw the line at attaching my inefficient headphone to an outside wall outlet at Three Mile Island ("enough is enough").


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## Pharmaboy

Paladin79 said:


> I looked inside the one I have and I could easily build such a thing. While pricey, mine uses a nice heavy cabinet and offers a quarter inch Jack as well as balanced out. Mine is currently hooked to a Cary amp.



Do my eyes see a sandbox-platform supporting a turntable? I built a couple of those for people years ago. Best way I know of to isolate a TT from physically-transmitted vibrations


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## geoffalter11

I just picked up a Code X.  87.5 spl.  I thought it would be way too inefficient for the HP8.  I was wrong.  The HP8 powered it on the medium impedance with aplomb.  Just slays that headphone.  So much tone, great bass control and the HP8's super power.  That slighly warm and gentle yet powerful midrange.


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## Paladin79

Pharmaboy said:


> Do my eyes see a sandbox-platform supporting a turntable? I built a couple of those for people years ago. Best way I know of to isolate a TT from physically-transmitted vibrations


Not quite yet lol, I got the frame made and added some supports underneath but I still have to finish the plinth. That is a very good idea though and I may well use it. Any details would be appreciated.


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## Pharmaboy

Paladin79 said:


> Not quite yet lol, I got the frame made and added some supports underneath but I still have to finish the plinth. That is a very good idea though and I may well use it. Any details would be appreciated.


If by "plinth" you mean the rectangular piece of wood that fits into the sand-filled box/frame, it's easy:

Any sturdy, multi-ply furniture grade plywood will do it. My favorite is 3/4" birch plywood. Just cut so there's ~1/2" on all sides of it when inset into top of the sand-filled frame. This wood need not be finished or painted unless you feel like doing that
The sand should be as fine as possible. I used "play sand"
The hardest part is leveling the sand in the frame/box to avoid imbalance of the TT or any "rocking" on humps of sand (you just rake the sand w/a straight edge that just shorter than the cross-sectional measurement of the box & you'll get there
Then you should be set
BTW, it's OK if the top of the plinth piece stands proud of the box somewhat, so long as it's not excessive. The main thing is getting the sand level (and keeping the cat from peeing in the sand ... that's a "whole other problem")
I see spikes on the bottom of the TT. A note about vibration control: the sandbox approach takes care of physically transmitted vibration rather thoroughly, but airborn vibration still exists and can get into the TT that way (woofers, subwoofers, heating systems or well pumps firing up, etc). To control the airborne stuff, you may need to use different, more massive vibration control "pods" beneath the TT.


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## gimmeheadroom

Pharmaboy said:


> But I draw the line at attaching my inefficient headphone to an outside wall outlet at Three Mile Island ("enough is enough").


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## Paladin79 (Tuesday at 2:42 PM)

Pharmaboy said:


> If by "plinth" you mean the rectangular piece of wood that fits into the sand-filled box/frame, it's easy:
> 
> Any sturdy, multi-ply furniture grade plywood will do it. My favorite is 3/4" birch plywood. Just cut so there's ~1/2" on all sides of it when inset into top of the sand-filled frame. This wood need not be finished or painted unless you feel like doing that
> The sand should be as fine as possible. I used "play sand"
> ...


Plinth means base but many consider it the inside that might hold the tone arm, motor, etc.

I used solid one inch birdseye maple for the frame, easy enough to fit a bottom onto it, level the sand and then I may again use maple. I tend to use hardwoods because I have good sources. I really like your idea and will certainly use it. All of my racks are on a tiled floor and I custom made my rack system using copper and solid cherry. I do not suffer from any flagpole effect. Approximately 300 lbs of weight including amps and shelves.

I also use solid hardwood for amps I designed, one such is below with a solid copper top that adds two lbs to the weight. I like a good solid bass for tubes, all wood is at least 3/4 inch. In this case tiger maple.


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## Pharmaboy

Paladin79 said:


> Plinth means base but many consider it the inside that might hold the tone arm, motor, etc.
> 
> I used solid one inch birdseye maple for the frame, easy enough to fit a bottom onto it, level the sand and then I may again use maple. I tend to use hardwoods because I have good sources. I really like your idea and will certainly use it. All of my racks are on a tiled floor and I custom made my rack system using copper and solid cherry. I do not suffer from any flagpole effect. Approximately 300 lbs of weight including amps and shelves.
> 
> I also use solid hardwood for amps I designed, one such is below with a solid copper top that adds two lbs to the weight. I like a good solid bass for tubes, all wood is at least 3/4 inch. In this case tiger maple.


Love that curly maple. Is the contrast wood ebony? Wenge? Those woods certainly look good together.

Before I didn't notice the splines or bass hardware on the frame. So you'd have to fit an interior bottom to the frame, as you say. All well worth doing in pursuit of greater clarity & solidity of the TT sound.

What is the copper tube amp with the wood frame (final picture)? It's knockout pretty.


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## Paladin79 (Tuesday at 5:23 PM)

Pharmaboy said:


> Love that curly maple. Is the contrast wood ebony? Wenge? Those woods certainly look good together.
> 
> Before I didn't notice the splines or bass hardware on the frame. So you'd have to fit an interior bottom to the frame, as you say. All well worth doing in pursuit of greater clarity & solidity of the TT sound.
> 
> What is the copper tube amp with the wood frame (final picture)? It's knockout pretty.


Honestly I forget which dark wood I used, not ebony or wenge for sure lol I turned a cylinder of it on a wood lathe and then quartered the cylinder for the corners. Three attempts before I got it right. I did use ebony for the splines on the turntable base. Making an interior bottom is not an issue for me.

That amp is one I designed and built for several friends, I called it the Incubus Elegan. 6sn7 and 6080 equivalent power tube. That one in particular I gave to a friend who sent me so many audio tubes I lost count. I made his sideways, controls on the side. This is my own in steampunk style with a Faraday cage over the power transformer. I added patina to the solid copper top. The cabinet is honey locust with purple heart splines.


Naturally it is a Class A amp, I run nothing else.  Sorry I will let everyone get back to the theme of this thread.


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## geoffalter11

gimmeheadroom said:


>


I love this!!! I saw Gil Scott perform in Emeryville, CA in 2005.  I saw Roy Ayers at the same jazz club a few days later.  Probably my favorite 2 concerts of that 10 yr period of time.  Also, seeing the Original Funky Meters at the Fillmore in SF in 2006.  That show blew me away as well.


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## geoffalter11

here you go...


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## geoffalter11

A few more fun ones...



And one of my all time favorite songs...


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## geoffalter11

Roy Ayers/HP8/Comet+/Atrium is making some pretty sweet music.  

Cen.Grand DSD DAC1.0 Super Clock will be here in the next 2-3 weeks.


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## geoffalter11

This was my first album.  I got a 2nd pressing from Japan at an obscure vinyl store in San Francisco 20 yrs ago.  Wish I still had it.


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## geoffalter11

Not sure I have ever heard a funkier, more sensual down beat.  This song just moves...


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## jonathan c

geoffalter11 said:


> Not sure I have ever heard a funkier, more sensual down beat.  This song just moves...


Try this _album….   _


  [Liberty / United Artists, 1975] _…. _on this…. 

[RCA ‘narrow gap plate’ 6SN7s, Raytheon 5751 (windmill getter)] 🤣


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## Paladin79

jonathan c said:


> Try this _album….   _  [Liberty / United Artists, 1975] _…. _on this…. [RCA ‘narrow gap plate’ 6SN7s, Raytheon 5751 (windmill getter)] 🤣


Since you recommended it, I will check it out tomorrow.😁😁


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## jonathan c

Paladin79 said:


> Since you recommended it, I will check it out tomorrow.😁😁


….be ready to bump ‘n grind….🤣🤣


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## JerseyD (Wednesday at 1:15 PM)

Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


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## gimmeheadroom (Wednesday at 3:04 PM)

JerseyD said:


> Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


Get an Audio-gd M1 oops, R-1, or if you have the space and can spend 2K, get the R8 MK2.


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## Pharmaboy

JerseyD said:


> Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


I say stick w/R2R or NOS; both work extremely well with my HP8.

From personal experience I strongly recommend the MHDT Labs Orchid. It has a tube buffer circuit which gives the owner the option of tube rolling; my own tube rolling really changed & bettered the already terrific sound of this DAC. FWIW, I use it both for headphone listening & for speakers/sub listening. That means all is revealed: if the DAC has sonic deficiencies, they have nowhere to hide. The Orchid sounds great to me no matter how I listen.

Here's the Orchid sold by MHDT's U.S. distributor, Linear Tube Audio (who were excellent to deal with). BTW, I paid LTA a modest sum to add a 2nd RCA output to my Orchid. Having 2 outputs live at all times really opens up some flexibility and fun (ie, listen to the same headphone on 2 different amps, one after the other; listen to two different headphones on the two different outputs; use 2 divergent/different hp amps with the same DAC; etc):

https://www.lineartubeaudio.com/products/mhdt-labs-dacs

In the event you prefer a balanced output from the DAC, the Orchid is out (single-ended only) ... but a lot of people rave about MHDT Labs' top DAC, the balanced Pagoda. It's out of your price range purchased new, but sometimes you find them used.

If it were me, I'd also consider Audio GD's standalone R2R/NOS DAC, the R-1 (I'm an Audio GD fanboy):

http://www.audio-gd.com/R2R/R1/R1EN.htm


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## jonathan c

JerseyD said:


> Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


With RCA 6SN7s and an RCA 12AX7, you should get that ‘warm’ ‘liquid’ tube sound - without being cloying.


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## jonathan c

Pharmaboy said:


> I say stick w/R2R or NOS; both work extremely well with my HP8.
> 
> From personal experience I strongly recommend the MHDT Labs Orchid. It has a tube buffer circuit which gives the owner the option of tube rolling; my own tube rolling really changed & bettered the already terrific sound of this DAC. FWIW, I use it both for headphone listening & for speakers/sub listening. That means all is revealed: if the DAC has sonic deficiencies, they have nowhere to hide. The Orchid sounds great to me no matter how I listen.
> 
> ...


+ 100 on the MHDT Orchid. The balanced out is moot - the inputs to HP8 are RCA (SE).


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## JerseyD (Wednesday at 2:15 PM)

gimmeheadroom said:


> Get an Audio-gd M1, or if you have the space and can spend 2K, get the R8 MK2.


The M1 appears to be a preamp. I saw on the other thread that you meant R1 (as Pharmaboy also suggested).  Thanks!


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## Pharmaboy (Wednesday at 2:25 PM)

jonathan c said:


> + 100 on the MHDT Orchid. The balanced out is moot - the inputs to HP8 are RCA (SE).


Yes, a balanced out is moot for the HP8. But it wouldn't be moot for a 2nd headphone amp that can accept a balanced output.

The balanced version of the Pagoda has one balanced output pair and one single-ended output pair. These can be used simultaneously (just checked the manual). If it were me, I'd attach a single-ended amp to the RCA output pair & a balanced amp to the balanced output pair.





But if the only amp on premises is the HP8, I agree the balanced Pagoda would not be optimal choice...

PS: re preamp vs DAC:

1 - The Audio GD R-1 does not have preamp capabilities--though I can very easily be configured w/2 X RCA outputs (my fave)

2 - The Audio GD M1 is preamp only, not a DAC (didn't understand this before). But the R-1 is a DAC, like the Orchid & Pagoda

3 - Some DACs also have preamp capability (I own one like that, the Audio GD R2R-11 AIO). But none of the DACs mentioned above are in that category.


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## JerseyD

Pharmaboy said:


> Yes, a balanced out is moot for the HP8. But it wouldn't be moot for a 2nd headphone amp that can accept a balanced output.
> 
> The balanced version of the Pagoda has one balanced output pair and one single-ended output pair. These can be used simultaneously (just checked the manual). If it were me, I'd attach a single-ended amp to the RCA output pair & a balanced amp to the balanced output pair.
> 
> ...



Yes, the balanced option would be good if I ever plan to get a SS amp with balanced in like the Violectric V222 for example.  (Of course, if I go with the Orchid, I could eventually just go with the V202   

PS: The M11 is a preamp with no DAC as far as I can tell.  He meant the R1...


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## Paladin79 (Wednesday at 2:26 PM)

jonathan c said:


> + 100 on the MHDT Orchid. The balanced out is moot - the inputs to HP8 are RCA (SE).


Last weekend I concluded a DAC comparison that had an MHDT Orchid in the mix. 16 DACS ranging in price from $1299 to $6,600. I am trying to decide on my endgame DAC and 46 people took part in the blind comparison. If you want the results PM me, do not just say send it to me in this thread or I might miss it lol.  Fair warning, we use 25 criteria and music recorded to exhibit said criteria. A DAC might do well in 20 categories and get beaten by a DAC that does well in 23 or so.  We used two new versions of the YGGY, those were the only Schiit DACS in the group.

I will be giving the top five a long listen on my home system before I make my final selection. I only had numbers 3 and 4 out of the top 8 reversed so my conclusions were similar to that of the group.

Oh and how they do with the headphone amp in question I could not tell you, four amps I designed and built are our standard and this time we used four sets of Focal Utopia headphones, another favorite of my group.


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## Pharmaboy

Paladin79 said:


> Last weekend I concluded a DAC comparison that had an MHDT Orchid in the mix. 16 DACS ranging in price from $1299 to $6,600.


That's amazing!


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## Paladin79 (Wednesday at 2:32 PM)

Pharmaboy said:


> That's amazing!


Many of my local audiophile group had some of the DACS, the rest we bought as a group and they will be sold or returned if the companies have such a policy. $52,000 in DACS and then there are amps, cables, switch boxes, audio engineers, headphones and other setup.  We did this four years ago with 20 DACS but DACS change a lot in a few years lol.

Just please do not be offended if a favorite DAC did not do very well, we use music recorded just for this purpose and some of the newer test subjects have to be trained a bit how to listen.


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## Deleeh

JerseyD said:


> Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


For 1500§, take a look at the Gustard R26 R2R Dac.
It will probably go very well with the Eikon and if not match well.

I've had mine since last Saturday and I'm still blown away.
about it.
It's worth the money, you can skip the Ares 2 the 600$ more is worth it.


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## jonathan c

Paladin79 said:


> Last weekend I concluded a DAC comparison that had an MHDT Orchid in the mix. 16 DACS ranging in price from $1299 to $6,600. I am trying to decide on my endgame DAC and 46 people took part in the blind comparison. If you want the results PM me, do not just say send it to me in this thread or I might miss it lol.  Fair warning, we use 25 criteria and music recorded to exhibit said criteria. A DAC might do well in 20 categories and get beaten by a DAC that does well in 23 or so.  We used two new versions of the YGGY, those were the only Schiit DACS in the group.
> 
> I will be giving the top five a long listen on my home system before I make my final selection. I only had numbers 3 and 4 out of the top 8 reversed so my conclusions were similar to that of the group.
> 
> Oh and how they do with the headphone amp in question I could not tell you, four amps I designed and built are our standard and this time we used four sets of Focal Utopia headphones, another favorite of my group.


… 46 ‘people’….and 1 Finnegan? 😸…. the winning DAC determined by 😻? …. 🤣🤣


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## Paladin79

jonathan c said:


> … 46 ‘people’….and 1 Finnegan? 😸…. the winning DAC determined by 😻? …. 🤣🤣


It was like herding cats to get 46 people in place, four at a time to listen to the DACS. 400 scores were given per person. Everyone would have been paying attention to Finnegan and that would have made things worse.


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## Pharmaboy

Paladin79 said:


> It was like herding cats


FYI, cats say, "It's like herding humans" (I can relate)


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## Paladin79

I am building a custom meter box for a friend, solid cherry, five inputs, two out. Line level.


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## Pharmaboy

Paladin79 said:


> I am building a custom meter box for a friend, solid cherry, five inputs, two out. Line level.


Damn, that's wonderful!

We really need a WOOD, WOODWORKING AND HEADPHONE AUDIO thread here (or somewhere) where wonks like us can beat this topic to death and not hog other threads.


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## Paladin79

Pharmaboy said:


> Damn, that's wonderful!
> 
> We really need a WOOD, WOODWORKING AND HEADPHONE AUDIO thread here (or somewhere) where wonks like us can beat this topic to death and not hog other threads.


Sorry I am used to the Schiit audio thread and today they are talking cars and jet planes lol. I generally try to keep it in the audio area.


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## Jay Smith

JerseyD said:


> Having a great time listening to the HP8 Mk II Sig so far.  However, my Bifrost MB just died (again) and I'm not sure I want to pay to have it fixed or upgraded (again).  Any good DAC-HP8 synergy matches you might suggest?  I have not begun tube rolling to find my ultimate sound, but would like a warmish USB DAC from $500 to $1500.  The HP8 is not quite as tooooby as I might prefer, but I wanted OTC so I can use with my DCAs as well as ZMF and Grado. Thanks.


Try second hand OG Holo audio Spring DAC.


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## Deleeh

The Spring 3 is still highly traded on the second-hand market.
Sometimes a little less than the new price instead of half.
If you do find one, it would be a really good bargain for $1500.

The Gustard R26 is supposedly not far off the Spring 3.
The A26 is supposedly not bad as a Delta Sigma either.
You could also take a look at the Everzolo Z9 in a review - it didn't necessarily do badly as a Delta Sigma either. 

The 2 Gustard models would have the advantage of direct streaming pervLan if desired, and the option of going via I2S.
It depends a bit on your own requirements and what else the Dac should bring along in your personal taste.


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## Jay Smith

Jay Smith said:


> Try second hand OG Holo audio Spring DAC.





JerseyD said:


> Finally beginning to listen to (and burn in) the HP8 MkII Signature (with stock Psvane "David Shaw" CV181's and Gold Lion ECC83).  Paired with brand new Auteur Classic - so a lot of burn in to do for both!  Listening as I go.  Nice heft to the sound so far.  A bit brighter than I expected the pairing to be, but that may very well calm down after more hours of usage.  Warren at Audioarcan said "the Mundorf capacitors take a minimum of 15 - 20 hours to burn in," so I'm not jumping to any conclusions.  Of course, I'm already smiling while I listen, so any improvement from here is icing on the cake.


I like Shuguang Treasure Cv181-z in my HP8mk2.  Sounds just right.  The stock ceramic tubes look like Psvane 6SN7 HiFi series which I have and I prefer Shuguang more with rich warmer tone.


----------

