NFB wiring question

[catalin gramada]

Well I decided to run the nfb wire (blue/red) as far was possible from sensitive areas with nfb divider on the outputs to not carry big currents around.

[Helmholtz]

There shouldn't really be "big currents" in an NFB wiring.
But your method reduces signal voltage and current in the wiring. I like the idea.
As said, best solution would be a shielded cable like RG174.

[catalin gramada]

Well this is a whole point I started this question topic. Running very small nfb curent directly to the grid through a whatever wire onto chassis makes in my opinion (not sure if is right or wrong) more prone to unwanted oscillations due to inductive/capacitive wiring and emi interferences into chassis. My initial question regard instalation of a grid leak and grid stopper right to the socket was in this respect of possible problems which may occur...if any, please. I improvised a workbench where I am now, have no possibility to measure nothing around.

[Helmholtz]

What more can I say?

A well shielded NFB wire should prevent unwanted coupling and thus not increase instability.

No one can predict final stability of your amp and what compensation measures will be required.

[catalin gramada]

And swapped with a shielded wire as you suggested