prosonic combo weak reverb

[nosaj]

I have a red prosonic custome shop that the reverb is really weak on 10. I have tried new tube, new footswitch , new reverb tank and new rca cables but none increase the reverb any.

What component or components allow you to raise the reverb?

Thanks,
Jason

here is the schematic
http://www.blueguitar.org/new/schem/fender/prosonic.zip

[Mark Black]

Are you getting a decent amount of signal from the secondary of the reverb driver transformer? Should be enough to drive a small speaker.

If you unplug the RCA from the tank output and touch the tip with your finger do you get a pretty healthy buzzing sound (as in the recovery circuit is working well)?

[nosaj]

Are you getting a decent amount of signal from the secondary of the reverb driver transformer? Should be enough to drive a small speaker.

If you unplug the RCA from the tank output and touch the tip with your finger do you get a pretty healthy buzzing sound (as in the recovery circuit is working well)?

Well after switching the connectors around I do. A combo of that and a intermittant cable.

Now that that's solved, what components would you modify to achieve more splash, etc..

Thanks,
nosaj

[Mark Black]

Now that that's solved, what components would you modify to achieve more splash, etc...

Good to hear things are better.

I'm more of a fix-it guy than a modder - hopefully some of the other tinkerers on the forum can/will chime in regarding improvements.

[Bob M.]

On the Prosonic, R34 is the grid load resistor (470K) for the reverb driver circuit (12AT7 tube). Temporarily, sub in a 1 meg pot instead of this resistor. Turn the pot to various settings of the pot and see how it affects the reverb sound. When you find something you like better, measure the pot's resistance and solder in a resistor equal to your measurement instead of the old R34. Or you could trial and error it by subbing a 1 meg resistor or a 1.5Meg resistor for R34 and see how it sounds to you.

[nosaj]

Ok I've subbed in the 1meg pot but cannot really tell much difference on it. Any one have any ideas.

Thanks,
Jason

P.S. Changed reverb driver from 12at7 to 12au7 to 12ax7 which definately gives more reverb.

[isaac]

Did you check that the tube is getting sufficient voltage on the plate? It's possible a resistor in the power section is bad, the other thing is check the resistors themselves to see if they are actually resisting at all. Maybe one blew open.