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View Full Version : Sampling rules or procedures?



lenlen4
09-29-2000, 02:33 AM
Hi all,
I\'m interested in taking samples from two mediums: an acoustic instrument and from an audio CD with acoustic instruments on it.
Are there any sampling rules that one should follow in terms of how many .wavs are necessary to make a sampled instrument? For example, gigapiano has 21 wavs (i think) whereas a sampled juno 60 has just one. If your\'re sampling an acoustic instrument, at what notes or intervals do you take the samples? If you take a .wav from an acoustic instrument on an audio CD, is one .wav enough like it is for the sampled juno 60 or do you need more even though the physical instrument isn\'t there to tell where the notes are? If anyone can shed any light on this i would appreciate it as i would like to make some kick as$%^ samples!

Sam
09-29-2000, 01:26 PM
GS and all samplers can pitch transpose a single sample across
the keyboard if necessary, the process is much like playing a tape
faster or slower, though it is a bit different since ultimately
it will play the pitch shifted sample out to a constant
sample rate out (like 44.1KHz). To do this it will
stretch the sample in real time and then resample it.
On some samplers this can add unpleasant artifacts so
you use a lot of samples to minimize the artifacting
of a big stretch. In my opinion GS has a
really good pitch shifting algorithm, better
than most I have heard and mostly free from
damage even with a significant shift.

However a lot of instruments (especially
pianos and voices) have significantly different overtone
series across their range. If you stretch
these much they sound quite unnatural, and also
a sample pitch shifted up will not match well against
the next one pitch shifted down. For this reason
you generally want to sample a Piano at least every 5 semitones as a
minimum.

But then I\'ve compared multisamples of
like 10 sawtooth waves to a single one stretched
and there\'s virtually no difference. So with
synthy, unnatural tones you can get away
with a lot, but with harmonically complex sounds
where people expect a certain timbre in a certain
range (natural, well recognized sounds like
accoustic instruments, it\'s best to use a
lot, it sounds better and makes a more
int4eresting and believable instrument.

I usually shoot for 4 notes/octave if I\'m working
fast but still want good quality. And velocity switched
layers is also very good for accoustic instruments,
3 or 4 per note makes a great instrument

bigbanksmusic
02-28-2002, 09:57 PM
sam
you havent said how