[music-dsp] Article: antialiased sine waveform syncing

[george bezerianos]

On Tue, Jun 9, 2009 at 3:26 PM, Vadim
Zavalishin<vadim.zavalishin at native-instruments.de> wrote:
>> Not infinitely, just long enough - how long apparently depends on the
>> Cn discontinuity.
>> You can check yourself that it _does_ work. I conjecture that it has
>> to do with Taylor's Theorem because of the analogy i described quite some
>> times in previous posts (it's a good time now that you know what
>> I'm talking about to go through them).
>
> Yes, but how does this relate to emulating the hard-syncing, if the pieces
> of the slave waveform are much longer than the master period?
>

By letting the BLIT (master) having a different frequency from the slave.
The (_not infinite_) slave's output frequency response will have some
lobes centered at the waveform's overtones which will let additional
harmonics from the BLIT leaking - this creates the harmonic leakage
we experience with hard-sync. Note that the slave has to ring a
_specific_ (currently undefined) amount of time, an infinite one
would produce zero output at the moment that master and slave
frequencies have no longer integer ratio.

I suspect the amount of time the slave has to ring could be calculated in terms
of numbers of period with respect to the discontinuity order - but i
might be wrong there.

Yours,

George Bezerianos

> Regards,
> Vadim
>
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