I know this is a bit off topic since there's not a vero layout for this one (though it would be awesome if there were!) but I'm hoping someone can chime in and help me out.
I've built a bunch of the madbean kingslayers with no problem. However the last four I've built have this crazy squeal when all the controls are at max. It's more of a high-pitched whistle.
Schematic:
http://www.madbeanpedals.com/projects/Kingslayer/Kingslayer.pdfHere's what I've learned so far.
1. The squeal goes away if I turn any of the controls down to about 3o'clock (75%).
2. it doesn't matter whether the OD clipping is on and it doesn't matter which signal clipping I'm using.
3. I've tested with opamps from known working circuit but still get the squeal.
4. I've tried removing and replacing the zener, neither affected the squeal.
5. I get a squeal on all of the opamp outputs on the tlc274
6. If I remove the 5n6 at C15 the squeal goes away (but effectively flattens out the Tone control)
7. If I replace the tone control with a 5K it wont squeal when pegged (no surprise there).
8. With a 10k pot on the tone, I get squeal on pin 1, but pin 2 and 3 are clean.
Thanks in advance!
Any ideas what I should try next
Locked
