[FOXY]

Does anyone have extra PCB of the amp? 

 

[Powderclear]

  I think most would call it superior to the B22. 

I second this statement, but with some clarifications:
 
I had to go to Taobao.com to get a Chinese clone version as I have no clue where to get the PCB from here in US (which I would prefer). The Chinese clone uses Philips BC546/556, but I did have all of them tightly matched, and I bought the Motorola 2N5566's from a reputable local supplier. The MJE's are also well matched, more or less. I skip the onboard power and using a Sigma22 instead.
 
Sounds wonderful, and IMO, sonically better than the Beta22, passive or active ground.
 
But I must say, some LME49990/LME49600 opamp based cheap headphone DIY amps I got from Taobao are becoming serious contenders now. Their highs are so clear and well structured/defined, with unbeatable low distortion and dead quiet, black-hole, abyss like background. The dynamics are also excellent! If not for the slightly weak low end performance, it will be hard to judge which one is better.

 

[KBoz]

I purchased my Krell KSA-5 new in October of 1994 at a price of US$1,750 dollars.  That should have been the manufacturer's suggested retail price for the amp at that time.  I can't tell from the serial number if it was a very early model or not (26-87065).

 

[MDR30]

I second this statement, but with some clarifications:

I had to go to Taobao.com to get a Chinese clone version as I have no clue where to get the PCB from here in US (which I would prefer). The Chinese clone uses Philips BC546/556, but I did have all of them tightly matched, and I bought the Motorola 2N5566's from a reputable local supplier. The MJE's are also well matched, more or less. I skip the onboard power and using a Sigma22 instead.

Sounds wonderful, and IMO, sonically better than the Beta22, passive or active ground.

But I must say, some LME49990/LME49600 opamp based cheap headphone DIY amps I got from Taobao are becoming serious contenders now. Their highs are so clear and well structured/defined, with unbeatable low distortion and dead quiet, black-hole, abyss like background. The dynamics are also excellent! If not for the slightly weak low end performance, it will be hard to judge which one is better.

What amps are those?

 

[Joong]

you might try some SMSL VA-1 or 2.
They are wonderful. They may not be those opamp based ones.:rolleyes: