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Hi,

As this topic arose in this thread... just my 2 cts (==what I would do)
to get performance as well as stable processing[*] and a high (and none
the less stable, so being predictable) output quality:

   1. Chose a sane but fixed output-sampling-rate (44.1 kHz, 48 kHz, 96
      kHz ... any of these will do. I would rather not go far beyond 96
      kHz... Why? Given alias-"free" generators no one even can hear
      22.05 kHz tones...)

   2. For "low quality" (==real-time output) I would just run everything
      on that rate. Generators, filters, everything.

   3. For "high quality" (==rendering output) I would just run the
      generators (== Oscillators) on a /significantly/ higher rate. I
      would _not_ opt for alias-free waveform-generators (BLIP or
      something alike, as these are limited to only a small subset of
      the useful operations) but for a very high sampling rate (~16x
      oversampled) and down-sample immediately after the generators via
      stacked Sinc-Filters (to make this halfway fast at least). So we
      would get virtually alias-"free" sampled output on a sane
      sampling-rate. This is what I would feed into the filters and
      effects. So their output will be the same than with the
      real-time-preview (just without the alias).

By doing so, I bet that most (if not all) stability problems
("stability" in terms of audio-quality) of lmms will be gone...

cu
Stefan

PS: just my 2cts because I had (and still have) a hard time to get the
bandpass-filter stable over the whole range of sample-rates supported by
lmms (44.1 kHz up to 1,53 MHz...). With the above setup I just could
have "ignored" frequencies below say 25Hz  and everything would have
been fine...

[*] I personally regard a stable rendering quality which as closely as
possible resembles the real-time output (but of course without the
alias) as being essential for the acceptance of lmms against other
solutions, such as MusE or commercial products. Just because if one
presses the big render-knob he/she wants to know it sounds the same ...
just better (that is without the aliasing) than before...



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