why hello! Yeah, it’s gotta be hitting the Nyquist frequency somewhere. (and I did the same double take I think you must have done – there is indeed a note to myself that I should do a better job of clamping the note range, and I thought that must be the problem at first, but that’s before it gets fed to SC – all the engine.hz commands should be within the normal MIDI range.)
I hadn’t considered that Comb might be the source – I have no idea how it handles delays shorter than 1 sample, but on high notes, that could totally happen. The comb filter gets tuned to harmonics of the root note, sometimes very high ones. I’ll have to limit that.
edit: actually, I’m having a hard time reproducing this problem, and both in context on Norns and in an scide session, CombL and SVF seem to be surprisingly good at not blowing up at high frequencies. Comb gets a little weird when hit with DC, but then it recovers. I can also get the Norns reverb to cut out momentarily if I hit it with a ton of high frequencies, but it too comes right back once they’re gone. hmm. I thought maybe I could push a fix for this tonight, but I think I’m going to have to keep trying to break it before I can fix it…