Am 28.10.2018 um 10:46 schrieb Scott Cotton:
- the quantised pitch shift is only an approximation of a continuous
pitch shift because
the sinc shaped realisation of a pure sine wave in the quantised
frequency domain can occur
at different distances from the bin centers for different sine waves,
shifting bins doesn't do this
and thus isn't 100% faithful.
I think this is one of the problems, frequency wise it seems to work
better at 11025 Hz sample rate with 1024 FFT size
so I assume you would really need 4096 and 8 overlaps minimum for 44 kHz
Its hard to tell because I can't test more than 4 overlaps in Reaktor
right now, it will get too complictated
and with that temporal spacing it's diffcult to judge if a larger FFT is
all thats needed
I am not sure if I calculate the principal value of the phase difference
correctly
I just wrap it back into the -pi..pi range, which seems right to me but
maybe I am missing something
From the sound clip, I'd guess that you might have some other problems
related to normalising the
synthesis volume/power
that's possible, but either I don't understand this point or it wouldn't
matter so much?
The best quality commonly used pitch shift comes from a phase vocoder
TSM: stretch the time
and then resample (or vice versa) so that the duration of input equals
that of output.
that's what I did before but I am hoping to get something that is more
suitable for real time,
with less latency, calculating the forward transform and spectral
envelopes offline
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