Self-oscillating filters?

[Annabanna]

I haven't used self-oscillating filters in maybe two decades, but I have several laser type effects I'd like to create with them now, and seem to be having some trouble coaxing the sounds out of MSF. It wouldn't shock me if I'm missing something necessary to make it work, but I should also probably ask:

1) Are there filters in the meldaverse capable of self-oscillating?

2) If so, which ones, and why are certain ones preferable?

3) Any tips or tricks I should be aware of to get the smoothest sound out of them?

4) If not, is there some way to build something that behaves similarly in MXXX?

5) Are there any other techniques you're aware of, MXXX or MSF devices, etc that do something that sounds similar using other methods?

I know I have several synths that will do this kind of thing (Massive, Sylenth, etc) but I find them to be a pain to work with, I'm much more familiar with the MXXX workflow at this point, and I'm trying my best to develop instruments within MXXX where possible so I have a modular library where I can interchange generators and effects.

[Faiky]

Just turn up the resonance of a HP / LP (>6db) and maybe screw a compressor behind it, shout be working or not?

[Annabanna]

Just turn up the resonance of a HP / LP (>6db) and maybe screw a compressor behind it, shout be working or not?

I've tried cranking resonance on all the filter options I could find all the way up, and none seem to be doing it.

Checking to see if I've missed some setting, filter, or option... or if there is essentially some way to use MXXX to string together modules to replicate that kind of behavior if the filters themselves aren't programmed to be able to self-oscillate.

Are you referring to a compressor just as a way of increasing gain... or as a safeguard against blowing my eardrums out if self-oscillation kicks in... or is there some other function of a compressor in this situation I'm missing?

[whyterabbyt]

In real life, filters self-oscillate because there's actual noise generated by the circuitry. If digital filters havent been coded to inject similar noise, it wont happen, so you need to ensure there's -some- signal going into the filter.

[Annabanna]

In real life, filters self-oscillate because there's actual noise generated by the circuitry. If digital filters havent been coded to inject similar noise, it wont happen, so you need to ensure there's -some- signal going into the filter.

I get the basic idea, but I'm asking then what the closest approximation would look like. Running white noise through doesn't get the clean sound. Running square, pulse, or triangle waves always sounds too much like the original wave and not enough focus on the resonance. I've tried running something like a square wave, but dropping it down an octave or two, then filtering it out of the final product, but the sound is always too dependent on the filter settings.

Would the closest approximation be something along the lines of a sine wave that tracks the same modulations gong on with the filter so the filter is always pitch tracking exactly where the sine wave fundamental is?

[mystran]

In real life, filters self-oscillate because there's actual noise generated by the circuitry. If digital filters havent been coded to inject similar noise, it wont happen, so you need to ensure there's -some- signal going into the filter.

You don't really need noise for self-oscillation, but you do need some noise to get it started. A completely clean digital filter with a canonically zero input will produce nothing but zeroes even in self-oscillation, but if the filter is capable of self-oscillation then you only really need the tiniest bit of noise to trigger the oscillation.

No idea if the filters of interest here can self oscillate, but if they can then try some noise at very low (inaudible) levels and see if anything happens.

[whyterabbyt]

In real life, filters self-oscillate because there's actual noise generated by the circuitry. If digital filters havent been coded to inject similar noise, it wont happen, so you need to ensure there's -some- signal going into the filter.

You don't really need noise for self-oscillation, but you do need some noise to get it started.

Yeah, I should have been more clear that it didnt need to be continuous.