[sDIY](early) wavetable synthesis

[mbartkow at ET.PUT.Poznan.PL]

Paul van Nugteren <PMvanNugteren at gmx.net> wrote:

> If you'd use that method for changing the picth of a samled waveform,
> you'd have to have a dac with non-fixed sampleing rate. Small pitch changes
> (10%) aren't a problem (used in DJ CDplayers) but huge like an octave or 2
> octaves (200% resp 400%) the DAC in use should be capable of changing it's
> sampling freq. in a range of 10 oct. from 440Hz to say 20000 is about 4.5 oct
> 2^4.5* 44.1kHz=997kHz!!!
> 
> But this is just my humble view, I haven't got any theory in DSP

Paul,

digital-to-analog converters do not sample. Most of them operate in a continous
mode, and there is no concern for them, how often or how slow you output the
samples. Of course, there is a minimum settle time which should be respected,
otherwise distortions occur. But this settle time is usually below 1usec.

mb


--

Maciej Bartkowiak, PhD
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