GainWire Mk3 CFA pre/phone amp with very low distortion

I almost finished wiring, but encountered one big problem, input selection boards do not work, not connecting any input. This is Volume and input boards bought called Biino from diy-audio-shop.de | Platinen und mehr (Birger Maass). Unfortunately the shop is closed from this summer and no answer from Birger. Hi is a member on this forum and I've sent PM but no answer too.
The main control board I received is a bit different than the schematic in the shop and it looks when I change the input nothing was sent to the input board.
Display works correctly, even the volume control board.
I am desperate now and if, just in case, anyone has experience with this Biino I would appreciate any help.
Damir
 
Founder of XSA-Labs
Joined 2012
Paid Member
JP,
Is that a GW Mk3 in SMT?! Wow you are fast. It had no label and looks so different I couldn't be sure - but based on parts count, it is I believe a GW Mk3.

643585d1509648970-gainwire-mk3-cfa-pre-phone-amp-low-distortion-v1-png
 
Matching those SOT23's is a pain in the behind though. Although, truth be told, unmatched transistors in balanced configurations sometimes might help to increase second harmonic distortion vs third for a more pleasing sound. :)
Never understood why is a pain in the neek with sot 23. Or you do not have equipment for measuring. What about Toshiba sot363 lots of room for measuring a little small to the sot23.
Unmatched for more pleasing sound aliexpress, eBay,mouser,digkey for harmonics you like a nice mix so be happy
 
After a quite long delay I received replace biino control board, my balanced GW mk3 version is finished.

I was listening via Benchmark DAC2 connected to the GW mk3 balanced inputs.
Some photos here.
Damir
 

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GainWire mk3 finally playing in my system.

Loudspeakers: ORION from Linkwitz
Power amps:---100W CFA three channels per loudspeaker
Crossover:------Analog active from Linkwitz
Sources:--------Benchmark DAC2
------------------Denon DVD 3910
------------------TT with Denon MC pickup MC 103
 

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Hello Damir,


good news, that you make your volume and input boards working. I dont know, what happens to Birgers shop. He closed it more than one years ago and the shop homepage is also in dying state.What has been the problem wih Biino MK2? I use Biino MK1 with your GW MK3. and it's a pleasure to listen to it.


Maybe i can finish your my CFA120 lateral amp soon. It's your design with TO-3p Exicons.
On my first layout design, i had to do some workarounds (layout errors, but you know that ;) ). I think i fixed now all, and it is already mounted on the heatsink for first powering up.


All the best
Günni
 
Hello Damir,


good news, that you make your volume and input boards working. I dont know, what happens to Birgers shop. He closed it more than one years ago and the shop homepage is also in dying state.What has been the problem wih Biino MK2? I use Biino MK1 with your GW MK3. and it's a pleasure to listen to it.


Maybe i can finish your my CFA120 lateral amp soon. It's your design with TO-3p Exicons.
On my first layout design, i had to do some workarounds (layout errors, but you know that ;) ). I think i fixed now all, and it is already mounted on the heatsink for first powering up.


All the best
Günni

Hello Gunni,
Birger sent me new PCB mk2(he appeared after one year), first one he sent to me was not good, I don't know what it was, it says mk2 but the was difference comparing to the schematic. I short it's working now.

I used original Hitachi in the lateral CFA, but it should work with Exicons too. You know that amp I use in my other room and it's really really good, don't hesitate to build it.
Best wishes
Damir