Help with SoCal 50 Reverb tank

[thejoe]

The reverb on my Epiphone amp is not working. When I got it the springs were all butchered so I swapped them for new ones and now I just get nothing. Any Ideas?

Side Thought:
This reverb tank connects to the circuit, like most others, via RCA style connectors. It is tube powered... Can I use the RCA cables just to jump straight back into the signal path (bypassing the reverb tank) and essentially use the reverb control as an added boost?

-Joe

[Twist]

You wont gain anything by jumpering across the reverb in and out. The reverb drive is designed to see a particular impedance into the tray and likewise the reverb return is designed for a specific impedance. I would think it might cause unwanted noise.

[cbarrow7625]

An old trick on Fenders, to do exactly what you described, is to use a 470K reistor with a small cap in parallel (or not...season to taste) between the reverb send & return. The reverb pot on the fender then does become a boost.

I've never done it, don't know what it sounds like but I have read about it on multiple occasions. You won't hurt anyhthing if you want to try it. The 470K resistor is just to keep the gain tamed down a bit. A straight RCA cable would serve just as a test to see if the circuit works at all or if your problem lies elsewhere.

Chris

[thejoe]

Sweet. Thanks for the info. Are you saying the resistor is in parallel with the cables? Or that the resistor is in parallel with the cap? I'm kinda new at this, but i've worked with electronics before. How do I wire the resistor in prallel?

[cbarrow7625]

The resistor & cap are in parallel. just tie the leads from one end of each together.

The cap/resistor combo go in series with the cables (no reverb tak attached of course). what you are trying to do is just loop out of the send jack, go through the resistor and go right back into the return jack. It's that simple.

The easiest way to do it is to cut an RCA cable in half (assuming your reverb send/return jacks are RCA type) and solder the resistor/cap right in lin ewith the inner conductor. Just let the shields float (i.e., don't bother re-connecting the shield wires on the two halves of The cable).

Hope this helps.