JC-80 eBay PCBs & Power Train

[BigE]

Anyone compare this to Salas' DCB1?

 

[pinnocchio]

I have both the JC-80 and a balanced DCB1 and they are both extremely good in their respective ways. Keep in mind that the DCB1 has a gain of 1 and my JC-80 is set to 7.5 of gain. I would say that the stage is a little wider on the DCB1 but my preference is leaning toward the JC-80 but I do use both and like them both very much. I won't go into details but it is my personal taste.

Thanks
Do

 

[JKoch]

I have just received next PCBs from manufacturer.

 

[pinnocchio]

Very nice work! Can't wait to see the main board

Ciao!
Do

 

[JKoch]

Thanks. I waiting with ordering of the main board or rather two main boards: input sockets board and output sockets board. They are really big and very complicated so I want to avoid any mistakes on these boards.

 

[JKoch]

Here is the last part of PSU for the Preamplifier - AC Main PSU. In few days I will order PCB for it.

 

[JKoch]

Few details about all PCB (those made yet as well as under designing yet):
- material: FR-4
- thick board: 2 mm
- thick Copper layers: 70um
- finish of layers: Au plated
- solder mask: blue

 

[pinnocchio]

Looking good JKoch!

Really looking forward to see more pictures. These boards will be really nice!

Ciao!
Do

 

[JKoch]

AC Main PSU has just finished.

 

[Trainerman]

2SK389 and 2SJ109

HI Guys can you help please if I use the BL version of these FETS will I have to make any component changes around them? I'm using the "E" bay Jims board schematic.

 

[pinnocchio]

HI Guys can you help please if I use the BL version of these FETS will I have to make any component changes around them? I'm using the "E" bay Jims board schematic.

Actually you can send an email to Jims Audio, I believe he has some used pulls which are genuine but will cost you about 35$-40$ a pair. It is V grade parts.

It is just the Idss that is higher if I'm not mistaking, V grade is in the range of 12-20?? If you take the highest range of BL I'm jusre it would work. You can use 2SK170/J74 to replace them but need a really tight match and something to bind them together for thermal coupling.

Ciao!
Do

 

[Trainerman]

Thanks for the reply much appreciated will follow that up with Jims store

 

[finwbu]

Hi Jkoch,

nice Job 🙂

 

[Trainerman]

Hi Guys, What size volume pot works best with this JC 80?

 

[john curl]

A P&G is just about perfect.

 

[pinnocchio]

Hi JC,

Long time no talk! What's new and exciting on your side?

Ciao!
Do

 

[Trainerman]

Hi Guys, Sorry I meant what K value is ideal for a volume pot, thanks

 

[gk7]

Multi-Channel Rotary Fader RF15 | Penny + Giles - Penny + Giles

10k log would be RF15 2 D A

 

[pinnocchio]

Multi-Channel Rotary Fader RF15 | Penny + Giles - Penny + Giles

10k log would be RF15 2 D A

Yeah, that one looks pretty nice and solid!

I use 20K on mine but it is a R2R Shunt Ladder from AMB. Actually those whole a10 preamp but using the JC-80 modules instead of the a20.

Ciao!
Do

 

[Trainerman]

Hi Do, I am using a SE input and output so do I need to run the - input to earth? I appear to have around 50mv of offset from both boards and I am wondering if this is down to the earth's?
Thanks
Paul