[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]

  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.