dan40
Friend of Leo's
Looking at the schematic, I would say yes but I'm not well versed in reverb circuits though so take that with a grain of salt.
Garbly hissy noise on startup Princeton reverb
- Thread starter schmee
- Start date
Looking at the schematic, I would say yes but I'm not well versed in reverb circuits though so take that with a grain of salt.
Yes/yes. Notice the reverb pot only controls the "output" of that circuit. All the stuff before V3A, like all of V2, could still put some noise back into the dry audio path.
Thx!
^^^ Agree with all ^^^
The thing to do is clean the reverb pot with a aerosol non-lube control cleaner. CRC QD ("Quick Dry" #05103) is a good choice. Find it at most any hardware or auto parts shop.
Use the little red straw to blast the cleaner into the pot. Keep the pot covered with a paper towel to prevent the cleaner from flying around. While the cleaner is in the pot, vigorously rotate the knob back and forth through its entire travel about 15 times. Blast it again, and repeat.
Once the pot is cleaned, remove the knob from the pot, remove the nut that secures the pot to the faceplate, and remove the washer. Use a small screwdriver to carefully scrape off any corrosion where the washer rests. You want clean, shiny metal there. Reinstall the washer and nut, and put the knob back on.
All the above assumes you know how to discharge the filter caps in the amp chassis. If you are unsure how to do this, or uncomfortable doing it, DO NOT ATTEMPT because there may be lethal voltages in there. Never ever work on an amp that has filter caps that contain a charge. Even unplugged for hours, these caps might still kill you.
The thing to do is clean the reverb pot with a aerosol non-lube control cleaner. CRC QD ("Quick Dry" #05103) is a good choice. Find it at most any hardware or auto parts shop.
Use the little red straw to blast the cleaner into the pot. Keep the pot covered with a paper towel to prevent the cleaner from flying around. While the cleaner is in the pot, vigorously rotate the knob back and forth through its entire travel about 15 times. Blast it again, and repeat.
Once the pot is cleaned, remove the knob from the pot, remove the nut that secures the pot to the faceplate, and remove the washer. Use a small screwdriver to carefully scrape off any corrosion where the washer rests. You want clean, shiny metal there. Reinstall the washer and nut, and put the knob back on.
All the above assumes you know how to discharge the filter caps in the amp chassis. If you are unsure how to do this, or uncomfortable doing it, DO NOT ATTEMPT because there may be lethal voltages in there. Never ever work on an amp that has filter caps that contain a charge. Even unplugged for hours, these caps might still kill you.
Pete Farrington
Tele-Meister
If the V4 cathode bypass cap, or its connections, are bad, high reverb settings can cause a howling oscillation, which people might confuse with acoustic feedback on the tank. Not sure if that correlates with the issue here.
Whatever, as the cathode bypass caps have been replaced, perhaps there’s a bad solder joint causing the intermittency, so consider reflowing them.
Whatever, as the cathode bypass caps have been replaced, perhaps there’s a bad solder joint causing the intermittency, so consider reflowing them.
I replaced the pot a couple weeks back, no change in the problem.
Also, my post #17 a couple days ago: " Latest: Today I went out to play it. Yesterday I had unplugged the reverb tank cables. I connected them today and played for probably an hour or 45 minutes. No noises whatsoever. UGH. I hate intermittant issues.
But hopefully, it was dirty RCA sockets and when I removed and reinstalled the cables things got OK. Fingers crossed...."
I cleaned the cables/jacks and actually put a different set in it. Time will tell....
