[sdiy] Dithering 8-bit waveforms (was Re: PPG or Prophet VS waves for class)

[Olivier Gillet]

> I'm interested in the 'band limited' tag of the shruti-1.
>
> Do you mean by that you band-limited the original waveform set when reducing
> it to whatever bit range / frequency base the shruti-1 uses or did you
> implement any simple band limiting system as part of the interpolation /
> wave playback algorithm ?

This concerns the "classic" waveforms only.

- The saw oscillator is implemented with a wavetable containing an
increasingly band-limited sawtooth wave. Depending on the pitch of the
played note, a waveform with the corresponding bandwidth is selected -
with interpolation / crossfading to avoid "skipping" when switching
zones of course (sort of like what is done on the Korg DW).
- Square oscillator is done with two dephased sawtooth.
- Triangle oscillator also uses a dedicated table.


Olivier