The capacitor you've connected to at that red line 'appears' to be an input capacitor for the channel in question. It's purpose (normally) is to block DC (isolation in effect) to the input and the way the gain is staging is 'probably' a result of how the channel references the signal when it adjusts gain either by gain control or pad changes etc.

I'd connect to the other side of that capacitor as the gain referencing is probably being 'looked at' from that side of the capacitor and the capacitor will prevent your signal from being 'seen' when on that red line side of it by the feedback side of the circuit. Hope this makes sense and it is best guess from limited info on the circuit but some concepts don't change.

Try that and see if the gain control then operates correctly.

Great to hear the beginnning of success.

Cheers Dyo!

So, no DC anywhere and same behaviour on the other side of the cap.

The lack of knowledge about this design force me to let it as it was meant to be.  

With some reflection, I am not shure about the fidelity of this mod (executed by me...) and if it let me down during a session or break something else, that won't help me at all, so the Octa-Capture is my best bet, letting go of the Adat interface of a 2nd vs-r.

Someone with better understanding could probably succesfully mod it but I'll have to stop here.

Thanks for all your advices and support through all this!

Dyonight, I'm assuming you open up you VS700R.  By any chance did you note how the fan is set up and if it would be easy to replace it.  Mine is getting louder and wouldn't mind knowing what would be involved with replacing it.

Cheers,

jayson

Mully


Fair enough Dyo and at least you had a solid go to your comfort level... kudos to you sir. It's tough to nut this stuff out without the proper gear and fundamental circuit knowledge. It is certainly doable so points to you for the idea and your efforts... the levels you are playing with are small so you'd be hard pressed to let the smoke out of anything unless you REALLY have no idea about what you are playing with but I can certainly appreciate your stepping away after going as far as you could. Cheers!

Thank you Mully for your nice advices. At one point I was really thinking I was going to nail it!


I have some experience noodeling with analog circuit and I thought I could find this split point but I feel that the design used is hybrid and my knowledge stop there! At least I can say that I've done what I safely could.