Reverb issues

[hesamadman]

Ive had great success with installing a solid state blues jr reverb into my hoffman AC30. However after switching from a PPIMV to a master volume right after my cathode follower tone stack, I cant get the reverb to work UNLESS the master is turned all of the way up. I was wondering if there is a solution other than switching back to PPIMV? At the very least maybe someone give me some reasoning behind this. My reverb is installed where the fx loop would be. It is in parallel with the circuit. I have the coupling caps set up on my hoffman just like the blues jr. It has a .033 and a .01 in series.


I moved the master volume. Off the tone stack. And moved it PASSED the reverb. Almost directly to the PI inputs, but I put a 500pf cap after the MV and before the PI input. It still does the same thing. If I turn the MV all the way up the reverb works fine. Confuses me since the Blues Jr MV is in the same place as I have this one.

[sluckey]

RE.. Blues Jr. The input for the reverb is taken directly from the MV wiper. The output of the reverb returns to a .01 cap just prior to the PI grid. There is a 220K resistor and a .033 cap between the MV wiper and the .01 cap just prior to the PI grid. Do you have that 220K and .033 cap in your circuit?

[hesamadman]

I had the 220k there. I also had the .033. Once I moved my MV back to PPIMV it worked. It's crazy.

[hesamadman]

Im not really sure exactly what I did to make this difference, but the reverb is not nearly as strong as it once was. I made some slight changes to the preamp but as far as the reverb goes, it is exactly the same. When the reverb is cranked all the way up, there is reverb but not nearly as much as there was before. And any setting before noon has zero reverb. Im coming out of my tone stack and then hitting this reverb circuit exactly like the blues jr. I now have a PPIMV. Im trying to figure out what I can do to bring it back. I think the only thing I changed really was the plate resistors in the preamp. I now have 220k rather than 100k.


Ive noticed that replacing the 220k resistor that is located after the MV wiper on the blues jr print with a 1m resistor, it eliminates a little noise and adds more reverb to the mix. It also yields a loss of gain. Which is fine. I put a 1m pot there and adjusted it. I cant actually tell by listening if its a good or bad change to the over all circuit. The 1m setting gives most reverb. Maybe I am being too picky. Im just hoping im not screwing up the overall tone of the amp by getting the reverb I want.