Shielded wire for NFB?

[daz]

I have a variable NFB pot and it has a wire run from the tap to the pot on the front then to the board where the resistor is. Just wondering, is it wise to shield NFB signal if the run is pretty long?

[soundguruman]

You can shied it if you are having problems with the feedback bleeding into other circuits.

[daz]

You can shied it if you are having problems with the feedback bleeding into other circuits.

Not that i know of, but i was wondering more along the lines of noise in general.

[soundguruman]

I have a variable NFB pot and it has a wire run from the tap to the pot on the front then to the board where the resistor is. Just wondering, is it wise to shield NFB signal if the run is pretty long?

The feedback goes to the phase inverter, and is a lower gain circuit. So, generally there is not a noise problem.
In some layouts, where you have the feedback crossing over the first stages, that can cause noise and oscillation.
If your layout is good, then you have no problem.

[trobbins]

Depending on your circuit impedances, close proximity of a feedback wire to OT primary windings/field could be an influence. Routing any such feedback wiring to stay clear of high voltage OT primary side signals would normally work, but shielding may be of benefit across the audio frequency range.

I've needed to be carefull with restoring old amps where the OT mounts to the chassis where half the exposed windings sit underneth the chassis (whatever that mounting format is called - "HL" or horizontal I think).