GHR Audio

Heikki wrote: Sat May 17, 2025 1:15 pm
Plastic standoffs under the PS board to make sure to make sure the solder mask doesn't break.

hmmm... Just forward thinking ??

SC55 earlier LM394 Version

Until Heikki arrives, I've attached a translated version of the document that is at the bottom of the vari mu home page.

https://ghr.fi/varimu.html


It's translated from Finnish

Towards the end it talks about the theory of transformerless.

Thanks. No worries on the post.
You answered the question I had.

I think it was brought up to me in the past but, what are acceptable input levels for this unit . I'm guessing it's determined by what the input INA chip can handle?
The gain pot's are after and would affect the tubes so this would be the best place to try and push level for effect? But this would ...

Heikki wrote: Wed Jul 03, 2024 1:32 pm Even when threshold is at max, large enough input signal will start gain reduction.

...Thank you!

I noticed that when I have the threshold all the way at max, I still get led meter action when turning the input gain up. Is this normal? What are the leds indicating?
Thanks!!

I can make out U5 on the DCDC board pic. What model Recom is used?

Looking at this thread
https://groupdiy.com/threads/fairchild- ... st-1126299

Would the 660 psu work for what he's trying?