Bedrock 600 - Lower Reverb Gain, how to

[Guitarist]

This amp had a couple issues one being the CF resistor was cooked. Now the reverb gain circuit has to drop as it oscillates (especially into the clean channel which soaks in more reverb than the high gain ch.) When clean and reverb are cranked it goes haywire.

I dropped in a lower gain op amp, but what's another low gain option aside from the original tl072?

? How does one lower the gain of the current op amp reverb circuit?

[Guitarist]

I see there's feedback to the inverted inputs 2 and 6. But still a bit lost with this. The hysterics seem to coming from the first half. Can I lower R2?

Got this from Wiki: "If predictable operation is desired, negative feedback is used, by applying a portion of the output voltage to the inverting input. The closed loop feedback greatly reduces the gain of the amplifier. If negative feedback is used, the circuit's overall gain and other parameters become determined more by the feedback network than by the op-amp itself.

[Jazz P Bass]

First, what is a cooked CF resistor.
Second. I would not mess with the reverb circuit.
Especially the drive portion.
I mean if there is a fault there, yeah, fix it.
I do not think a redesign will help.
Look at the input to the opamp.
Is the signal going bad there?
The opamp is set to follow.
If you have a bad input to it, I think that you can guess what will come out.

[Guitarist]

Ah OK Cathode Follower resistor. The 1/2 watt I replaced with a 1 watt.
The amp works perfect now, but there is way too much reverb send gain so I need to introduce some negative feedback with a trimpot likely. I just could use some clarification. Along with the OP, those diodes and the monster transistors are just screamin'.
The reverb isn't that great anyways and a bit less will be fine. The company had major warranty issues and I'm just trying to get this amp working stable asap. The layout looks marginal.

[Guitarist]

This amp is fraught with internal noise. I had to move transformer wires around to get it quieter. This was augmented by that high gain reverb circuit. Amp is now usable with a couple lower gain tubes.