Actually I can do a filter with time varying filter at audio rate with _NO_ glithces or artifacts, stable (essentially behaving like an analog one). The point is that the BLIT harmonic content changes in modulation (because you have to cut harmonics as you are sweeping hi) and that results in spikes in amplitudes that are before the integrator (so the BLIT itself in modulation clicks and pops). Since freq change could not happen at perfect zerocrossings this effect is unavoidable (unless keeping the same harmonic content for BLIT thus aliasing in sweeps which is awful to hear). Also trying to change freq at zero crossing fails as your freq reaches high values where periods are of a handful of samples.
M. -----Messaggio originale----- Da: music-dsp-boun...@music.columbia.edu [mailto:music-dsp-boun...@music.columbia.edu] Per conto di robert bristow-johnson Inviato: mercoledì 26 febbraio 2014 19:15 A: A discussion list for music-related DSP Oggetto: Re: [music-dsp] R: R: R: Best way to do sine hard sync? On 2/26/14 12:37 PM, Marco Lo Monaco wrote: > Moreover in my experience BLIT with leaky integrators fails on > frequency modulations, i can imagine why. it's sorta like how some IIR filter topologies fail with coefficient modulation. this is another reason that i am a proponent of wavetable synthesis in all contexts where memory resources allow. wavetable synthesis is more like a basic FIR filter: nothing to blow up when parameters are modulated. -- r b-j r...@audioimagination.com "Imagination is more important than knowledge." -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
