GainWire Mk3 CFA pre/phone amp with very low distortion

Any duel executed?
No. I also have the original pcb, but in the end I built on the boards from @platon.rado, I always wanted a dual mono preamp. I already have Gainwire done, both pcb's worked on the first power up. I have yet to assemble the controller, switching on the front panel with the blue led. I am currently hesitating whether to buy a TKD 2CP-2511 potentiometer or a 48 stepeed atteunator ELMA. Input switcher will be from ELMA, I only need 2 inputs (DAC, Phono). I'm still thinking whether to invest in high quality cinch connectors (copper+gold) or just buy ordinary ones (brass+gold)
 

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My opinion is that digital potentiometers are not good enough, the GainWire mk3 preamp has much lower distortion, only passive resistors attenuators are good enough, even best dual potentiometers as Alps or other kind have to big differences between tracks.
I also ruled out digital volume control, I was deciding between the TKD potentiometer and the atteunator. In the end I leaned towards the attenuator from Khozmo (48 steps), ...which is on its way.
 

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I'm just waiting for the internal cabling from Neotech (pure cu for power supply & pure silver for signal wiring) Furutech connectors and the Elma switch.

The Gainwire MK3 will eventually only be used as a preamplifier. The headphone amplifier will be a DCG3 from Salas.
 

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Friends small update, modushop 2U case. I still have to draw the front and rear panels, ...send them to production.

I am still considering whether the headphone output will be in the front or in the back.
I bought top quality headphones, but with very low 25ohm impedance. I just hope that gainwire mk3 can handle them...
 

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HRDSTL, you dit not finished GW mk3 on the original board as I understood? With original board you do not need two mains transformer to have dual mono.
There are separate shunt regulators per side, so it is dual mono too.
Do you have any problem with the broom with those boards you used?
 
HRDSTL, you dit not finished GW mk3 on the original board as I understood? With original board you do not need two mains transformer to have dual mono.
There are separate shunt regulators per side, so it is dual mono too.
Do you have any problem with the broom with those boards you used?
I only have it temporarily wired up, wiring hastily... to test the sound quality of the GainWire MK3. No hum or noise, the amplifier is completely silent. I compared the sound of the Gainwire MK3 to the hearing aid output on my Audiolab 6000A and it's an incredible difference! I've always wanted a dual mono preamp.

Power supply in my case is very simple CRC (2200uF+2R2+2200uF) + 7815/7915 + 2200uF

Today I would like to draw the front and back panel and send to production for milling, engraving. GainWire MK3 definitely deserves attention, ...everyone should build one.
 
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Friends I'm almost done, I still have to bring out the coax to the connectors for the pre-out. It really is an excellent preamplifier, I recommend everyone to build one. Here on the forum, people tend to build simple projects that don't sound as good as complex ones.

As I mentioned above the preamplifier has no audible noise, and when following the principles of proper GND routing, no hum. I'll take pictures of all the details during the week...
 
HRDSTL you did not use my PCB, why then you want to improve?
I don't suggest use a relay to connect headphone, specially not low impedance one, it could degrade sound.
You can use delayed preamp output for the power amps.
Could you point what kind of Molex connectors?