Luxury 763 Oscillation Issue

[gheorge77]

So strange. First time in building probably 40-50 pedals where I have gotten a bad oscillation on this build. I switched the IC with no change. Curious if anyone else has experienced this issue and has a clue on the cause. Thanks!

-Ian

 

[Dan0h]

So strange. First time in building probably 40-50 pedals where I have gotten a bad oscillation on this build. I switched the IC with no change. Curious if anyone else has experienced this issue and has a clue on the cause. Thanks!

-Ian

Do you happen to have it powered via a daisy chain? I ran into the same issue before and now always make sure to have it on its own power line.

 

[gheorge77]

Do you happen to have it powered via a daisy chain? I ran into the same issue before and now always make sure to have it on its own power line.

I was just testing it on a one spot, which causes no issues on any other builds.

I'm thinking it relates to the IC somehow but I'm not sure why yet. I guess I can try some IC swaps as well. Seems like oscillation is not an uncommon issue with the NE5532 based on some threads elsewhere.

 

[Chuck D. Bones]

I have not had any problems with NE5532 oscillation.

I have some questions:
1. Have you performed a thorough visual inspection? I see that all of the resistors and C5 are correct. The outboard wiring looks good. I can't read the other caps or get a good look at all of the solder joints.
2. Do you have insulators on the BASS & TREBLE pots?
3. Does turning the BASS, TREBLE or DRIVE pots cause the oscillation to change?
4. What does the oscillation sound like? Buzz, squeal, warble?

 

[gheorge77]

I have not had any problems with NE5532 oscillation.

I have some questions:
1. Have you performed a thorough visual inspection? I see that all of the resistors and C5 are correct. The outboard wiring looks good. I can't read the other caps or get a good look at all of the solder joints.
2. Do you have insulators on the BASS & TREBLE pots?
3. Does turning the BASS, TREBLE or DRIVE pots cause the oscillation to change?
4. What does the oscillation sound like? Buzz, squeal, warble?

The caps are all correct. Double checked that. No insulators on anything but did check out of the first enclosure moving the pots and the same thing is still happening. The oscillation starts when the drive is roughly at 50%. The treble and bass modulate the frequency of the oscillation. I'd call it a warble more than a buzz. Def not a squeal. I'm wondering if I have a solder bridge somewhere that I cannot see at all.

 

[gheorge77]

The caps are all correct. Double checked that. No insulators on anything but did check out of the first enclosure moving the pots and the same thing is still happening. The oscillation starts when the drive is roughly at 50%. The treble and bass modulate the frequency of the oscillation. I'd call it a warble more than a buzz. Def not a squeal. I'm wondering if I have a solder bridge somewhere that I cannot see at all.

Just bumping this back up for some other suggestions.

 

[Chuck D. Bones]

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