I have a second hand Moog Little Phatty and just noticed that the pure Sawtooth wave ( 1 OSC only, Resonance=0, Cutoff = open ) sounds a little wheezy and distorted in the middle and high range. There is the same effect with both of oscillators, the effect is similar also if I use different waveforms . I can hear it very well using the monitors (speakers). Its difficult to hear the distorted sound using headphones.
I compared it with a filter open sawtooth wave on my Minitaur and Nord Stage 2 that sound very clean in comparison with the LP.
I have used also different audio and electric cables. LP has the same problem.
I noticed the filter cutoff on my LP Tribute was scratchy and jumpy - it was kind of sticking and then jumping instead of being smooth and continuous.
I ended up “exercising” the knob, turning it back and forth like 40-50 times. Seems to have done the trick! Not sure if this is related to your problem but figured I should mention it. My LP is probably around 10 years old, and sits around a fair amount without being used. I have no actual knowledge that this is a legitimate fix for the problem I had, but I do know that it works for Alembic equipment that I own and is one of the first things to try when diagnosing the problem.
If I’m totally off-base, hopefully someone will come along and set me straight! I have a track that I used a slow, long filter sweep on - when it gets posted I’ll post it here for proof!
There is no modulation and overload is 0.
I understood what was the problem .I think is a grounding issue. When I plug LP and a Minitaur that I have in the same soundcard, I receive that wheezy/ buzzy sound . Also and that case I have a "Dancing Light " issue , that was observed at this forum.
The problem of grounding appears also when I put my LP to the MXR M222 talk box. The synth works fine with other pedals that I have. It Is a really strange thing
I have a track that I used a slow, long filter sweep on - when it gets posted I’ll post it here for proof!