Foreplay II 2nd grid stop resistor

[kuramura]

I have a Foreplay II C4S heavily modded that's been running  for few years. One of the upgrades was installing shunted volume control and at some point I've experienced buzzing that was changing depending on position of the pot. Someone suggested  to install grid stop resistor, 750 ohm cured the problem. Lately I'm getting noise that I think might be caused by bad 9 pin 12au7 socket. I will be replacing that soon.
My question is would there be any benefit to install small value resistor 330 ohm for example between sections of the same tube, before pin 7 ?

Thanks

 

[Paul Joppa]

The grid stopper should generally be anywhere between 50 ohms and 10K ohms. Sometimes different values appear to give different results, but the available reports are anecdotal and subjective, so it's hard to draw conclusions. Fortunately, it's easy to experiment using your own ears, which is after all the only measurement you can really trust!

As a scientist I am deeply skeptical about what your ears tell you. As a music lover however, I say if it sounds good it IS good. When in doubt I have to go with the latter.  :^)

 

[kuramura]

Thank you for your reply Paul.
So I understand that there should be no harm done to the tube or circuit by adding resistor before pin 7 ?

 

[Paul Joppa]

Thank you for your reply Paul.
So I understand that there should be no harm done to the tube or circuit by adding resistor before pin 7 ?

None at all.