> imagine it's two-dimensional vector synthesis like a Prophet VS. one > dimension is some other timbre parameter with a minimum and a maximum > (no wrap around). > > so, in the other dimension, imagine having say, 6 identical wavetables > except the 2nd harmonic is offset by 60 degrees in phase between > adjacent wavetable vector points in that dimension. all other > harmonics are exactly the same. so as you crossfade from wavetable 0 > to 1, that 2nd harmonic advances 60 degrees, as you crossfade from > wavetable 1 to 2, the 2nd harmonic advances another 60 degrees. > wavetable 6 and wavetable 0 are exactly the same. as you crossfade > from wavetable 5 to 6 you're advancing the final 60 degrees back to > the original phase of wavetable 0. > That makes sense, I'll have to try it. Six wavetables for the detuned partial seems like a good number, and I can see that you would not want too few of them. But what's the reasoning behind how many to use?
> now, if all of the other harmonics remain the same phase for all 6 > wavetables, moving around between them does not detune those > harmonics. but if you go around that circle (in the positive > direction) one complete loop, the 2nd harmonic made one more cycle > than it would have otherwise if the vector location was stationary. > if you whip around that loop 50 times per second, the 2nd harmonic > will be detuned higher by 50 Hz. if you whip around that loop in the > opposite direction, you will be detuning that 2nd harmonic lower in > frequency. > > the application where this might be useful might be with piano tones > or some other natural instrument with sharpened higher harmonics (like > above the 9th or 12th harmonic). it's a different (and cheaper) way > of doing it than employing what they call "group additive synthesis" > where the higher harmonics are put into a different set of wavetables > and run in a different wavetable oscillator that runs at a slightly > sharp fundamental. > On the other hand, I find group additive synthesis conceptually simpler when dealing with inharmonic partials. What is the maximum detuning a partial can have with the wavetable method? Intuitively I would guess it's the same as the fundamental frequency, so the harmonic k could be tuned down to (k-1) or up to (k+1) at most, is that right? Risto _______________________________________________ dupswapdrop: music-dsp mailing list firstname.lastname@example.org https://lists.columbia.edu/mailman/listinfo/music-dsp