grid stop resistors on the power tubes - criticality of placement

[pjd3]

Hello,

I would normally always position grid stop resistors right on the pin of any tube for all the known and apparent reasons a grid stop resistor is applied.

Do you think these reasons apply to a pair of power tubes in PP in the same way as an early stage preamp tube? Reason I ask is that while building up a turret board for an experimental circuit, I erroneously soldered the 2 EL34 5.6K ohm grid stops directly to the turret board which is about 3-5 inches away from the power tube sockets. Its not too much of problem to desolder them and move them to the tube sockets but would I be OK for powering up and testing the amp? (Is oscillation a danger risk here?) The amp is only to be run at low to moderate volume with super clean tone.

Are power tubes subjected to the same conditions as preamp tubes regarding grid stoppers?

Thanks for your input on this.

Best,
Phil D.

[maxkracht]

Plenty of amps do not have grid stoppers and I have seen a handful with grid stoppers on a board somewhat far away from the grids. It's definitely preferred to keep them at the tube sockets, but you would have to be insanely unlucky for a bit of distance to cause any significant problems.

[Stevem]

You will have no issue like that, the components that need to ideally be less then 4” away from each power tube grid is the coupling cap !
The greater the distance the greater the chance of oscillation and or muddy tone.

[dorrisant]

If you look at the Deluxe Reverb RI, Blues Jr, Hot Rod DeVille, Deluxe, etc., you will see Fender does the same thing as much as possible.
That said, this is also one of the first things I change whenever I encounter burnt screen grid resistors. Maybe consider moving them later.. ?

I install them (screens and grids) at the sockets and jump out the pulled resistors on the board.

[pjd3]

I surely will keep this in mind about the proximity of these components, and be ready to move them at the instant I think there current placement could be problematic.

I did already solder 1200 ohm resistors for the screens directly to the power tube sockets but, have decided those sockets stink and will be pulling them out for new solder lug versions. They were printed circuit board pulls from my old Bogner Alchemist. Just too shabby.

Thank you,
Best,

Phil