Thanks Enzo,

I took your advice and removed the reverb tank. No springs broken or out of place. I did take some Deoxit to the RCA plugs on both sides and gave the reverb pot a good dose too, working the knob back and forth for a good long time. Reassembled and voila! A working reverb and no startling pops when I adjust the level. Amazing!

So glad I discovered this forum! Please consider this post answered.

James

I pulled my very vintage Yamaha G100 112 from storage recently and found a really nasty issue with the reverb. The smallest tweak of the reverb knob results in a very (painfully) loud pop from the speaker, regardless of the volume knob settings on either channel. I love a little reverb, but I was forced to disconnect the reverb tank to use the amp at all. Thank goodness for RCA plugs. (I have minimal electronics know how, but I can disconnect things with the best of 'em.)

I live in the Southern California area and would like to have the amp looked over by someone with experience. Any suggestions are very welcome.

Thanks,

James