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Intractable problem

Date1998-06-26 16:23
FromCarlton Wilkinson
SubjectIntractable problem
Miss me?
Can anyone tell me, please, why this file compiles properly when I take
out the butterlp line, but returns c. 40000 samples out of range per
channel per note with close to 0 output when the butterlp line is
included?
I've streamlined this and tested what you see here and get consistent
results. The soundfile is a simple brake rotor being struck with the
flat of a hammer--a sound very rich in high partials, hence the need for
a butterlp. (For those of you who are already thinking "why doesn't he
compile the file first and filter it later?" The answer is: aliasing
produces clicks in midrange--can't filter the clicks without losing part
of the body of the sound. I know. I've tried.) The sndwarp opcode is
complicated, but I can't see how it and the butterlp are so related as
to produce such results. I'm in over my head.
The high number of overlaps and the small window here are a necessary
element, giving the sound a slightly raunchier attack. And it works
perfectly without the butterlp . . .? What the hell?

--
Carlton Joseph Wilkinson
http://excaliber.net/alex/wilkwrks.htm

;-----------------
;orc
;------------------
sr = 44100
kr = 44100
ksmps = 1
nchnls = 2

instr 3

;sndwarp parameters
kamp linen p4, .01, p3, .01
itimewarp = p9
iresample = p5 ;2 = octave above
ifn1 = 3
ibeg = 0
iwsize = int(sr/10)
irandw = iwsize*.2
ioverlap = 40
ifn2 = 4
itimemode = 0

a1 sndwarp   kamp, itimewarp, iresample, ifn1, ibeg, iwsize, irandw,
ioverlap, ifn2, itimemode
a1 butterlp a1, 14000
outs a1, a1
endin

;-----------------
;sco
;-----------------
f1 0 4 2 .1 .82 .82 .1    ; this orc and sco are intended to time
stretch brakerotor2.snd
f2 0 4 2 .82 .1 .1 .82    ; for use in a granular texture, the third
large section of black magic
f3 0 524288 -1 "brakerotor2.aiff" 0 4 0
f4 0 16384 9 .5 1 0

;   p4 amp
;    p5 transposition     2nd 1.125, M3rd 1.25, P5th 1.5
;      p6 passes between speakers
;       p7 phase offset (speaker balance)
;        p8 rvrbgain
;         p9 timewarp
a0 0 8
i3 8  4 .7  5.625  1  .5  .05 .3
i3 9  2 .6  10   .5  1  .05 .2
i3 12.5 2  .6  7.5  2  .25 .05 .2
i3 14.5 4  .6  6.25 1.25 0  .05 .3
i3 15.5 2 .6 5.625  1 .5 .05 .2
i3 16 4 .7 6.25 .35 .75 .05 .3
i3 17 5 .7 7.5  .5 1 .05 .4
i3 18 2 .7 10  .1 0 .05 .2
i3 19.525 4 .7 5   .75 .5 .05 .3
i3 23.5 4 .6 7.5  .1 1 .05 .3
i3 24.5 4 .6 6.25 1 .5 .05 .3
e