High pass filter on reverb recovery

[Chuck H]

I don't remember just how I did it. I think I bought a dual RCA thing mounted on a fiber board from Radio Shack and just oversized the holes by enough so the male jacks wouldn't contact.

[Steve Conner]

I used the fancy gold plated RCAs, and the supplier also had isolating washer kits for them. But that was purely for looks, Chuck's solution would work equally well.

FWIW, I did once use a high pass filter on a reverb recovery. In a combo amp I built, I was getting a low pitched throb of feedback from the speaker back into the tank. A smaller coupling capacitor shut it up and let me turn the reverb up higher.

[Chuck H]

The "thing" I built is a "reverb amp" You can plug the output of any tube amp into it and it filches about a watt to run the tank. It has an input sensitivity control and a meter on the front so it can be adjusted for amps from five to a hundred watts and the meter tells you when it's adjusted correctly. There are protection diodes in place so that a mis adjustment won't blow the tank. It also has volume and tone controls. It has two el84 tubes in push pull and it's own 10" speaker. Point is, keeping the pan from feeding back with the speaker at very high reverb levels was a bitch. The tank is wrapped in foam, then rolled in a vinyl sheet like a buritto with the ends of the "bag" screwed into the bottom of the cabinet. I then had to add more foam shims underneath to semi suspend the whole thing. But it works to full volume. Fifteen watts of just reverb from a 1x10 combo. Which, BTW, is waaay more reverb than anyone needs for anything but a hundred watt amp.

[jreese2001]

Hey everyone I just wanted to report back that after isolating the RCA jacks, the hum is completely gone. Thanks to everyone for your help !