Peavey Classic 30 - preamp hum

[Buddha's Guitar Tech]

Ah, cool.

Grounding stick you say? I've tried alligator clipping the ends of some electrolytic to the earth point, no joy there.

Chop-sticking has been done, oh yes.

edit - type-o... electrolyticS.

[selloutrr]

test the caps for leaks.

[Buddha's Guitar Tech]

Please pardon the apparent naivety in my question; do you mean DC where there should be no DC (couplers) or some other method with electrolytics?

This amp is such a pain to work on

[sixstringer]

I've repaired/modded several Classic 30's. Working on them is a challenge but it gets easier after you've done a few, sort of like it does with Vox amps.

When checking the jumpers between boards be sure to check the solder joints carefully, I've seen these crack and become noisy and intermittent, similar to the way the tube socket solder joints crack on Fender Hotrod series amps. You mentioned you replaced the input jack, you used shielded cable for the connections, right?

Steve Ahola's mods really improve this amp. Tweaking the overdrive channel values to get the right blend between the channels makes the od channel usable and it sounds much smoother. It is a surprising good sounding amp with the mods.

[dorrisant]

a good & quick way to check the board jumpers...
pluck each one with your fingers or a guitar pick... you just might have one or two of these around your house.
they should all "ping" when plucked lightly... any dull sounds indicates loose joint. i do this every time i prep to reinstall the boards.

tony

[Buddha's Guitar Tech]

dorrisant, that's the sort of crazy talking that gets results, i don't know if i like it.


i use pennies for picks - i'll get right on it.

[dorrisant]

also... the reverb in jack has to be isolated from ground... i usually replace the original with a cliff jack... food for thought anyway!

tony