libsidplayfp
Weird 6581 filter distortion
With 2.12.0, you can hear some odd distortion in some notes:
sidplayfp.exe MUSICIANS\0-9\20CC\van_Santen_Edwin\No_Mercy.sid -o3 --fcurve=0.7
i noticed that with Martin Galway's Wizball.sid with the same filter curve value as well, but i just assumed it was normal behavior
Sorry i realize i opened this issue in sidplayfp, but it should be more suited in libsidplayfp.
It's very obvious on Wizball indeed, even more so at higher curves. It's definitely not normal.
This has been discussed already in libsidplayfp/libsidplayfp#80 and related bugs. The 6581 filter is wild and may behave weirdly at extreme settings.
