Blew up my Ruby - need help fixing

[Rutger]

Last week I blew up my Ruby amp with a reversed 12V adapter pin.(Ruby Bassman amp from runoffgroove.com Ruby) It's one of those adapters with different pin-sizes, and I placed it the wrong way so the center became plus instead of minus...

Anyway, the 100uF elco and the IC were dead so I replaced them. I also replaced the JFET allthough it seemed okay. All the measured voltages around the IC and JFET are right.

Now there is a rattling noise all the time, and it changes speed when I turn the volume and gain knobs.
There is a signal when i play my guitar, but it's heavily distorted and it only comes through when I play hard.

Does anyone know what it is?

[loudthud]

Not much to this thing, could be a bad IC or your power supply is feeding it too much voltage. Try it with a 9V or 12V battery. Is there any DC voltage at the speaker when there is no signal? That would indicate a bad 220uF capacitor.

[Rutger]

Thanks Loudthud.

It sounds like a relay switching really fast.

I tried it with 9V and even with 15V, since it is an LM386-N4 which can handle 18V.

I checked DC voltage at the speaker, and there was a few tenths of volts during every 'tick'. I replaced the 220uF cap but...
Still the same ticking. The elco should handle 16V, or this elco is bad as well...

This build is becoming a pain in the ass, maybe I should rebuild it from scratch

[J M Fahey]

It sounds like oscillation to me.
Maybe when repairing it you left away or mis soldered something .
Sometimes you pull a ground wire which worked perfectly before, re-solder it one inch away , not giving it much importance (hey, a ground is a ground, isn't it?) and it becomes a PITA.

[Rutger]

Thanks JM. I checked all the solderjoints but I'll recheck again.
I placed the new elco's a bit different on the perfboard than the originals, so that could be it.