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Re: RT.SYNTH -- anybody tried it?
Linards Ticmanis wrote:
Michael J. Mahon wrote:
By a happy coincidence, the period of the PWM pulses created by
DAC522 is 46 Apple cycles, and your sampling scheme should reproduce
its output perfectly!
Well, RT.SYNTH is almost inaudible with it, so there must be *some* kind
of problem...
After looking over your sampled file, I'm sure that the problem is
just low volume. A PWM DAC has less sound "punch" than a bang-bang
squarewave. Perhaps an emulator "volume control" to adjust the factor
by which the on-count is multiplied (2x to 10x) would be useful.
There may also be an issue with the fact that you don't "center" the
samples around 128, which is "sound zero".
Wouldn't there be a high dependency of the output quality on just
*where* in the 46-cycle DAC522 cycle each new 23-cycle emulator sample
starts?
An examination of the sample file shows near perfect sampling,
so that's not a problem.
After centering the sound and pumping up the volume, RT.SYNTH sounds
almost exactly like it does on a real //e!
-michael
Music synthesis for 8-bit Apple II's!
Home page: http://members.aol.com/MJMahon/
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