Merge pull request #506 from andrewcsmith/patch-2
[supercollider.git] / HelpSource / Classes / BufCombL.schelp
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1 class:: BufCombL
2 summary:: Buffer based comb delay line with linear interpolation.
3 related:: Classes/BufCombC, Classes/BufCombN, Classes/CombL
4 categories::  UGens>Delays>Buffer
7 Description::
9 Comb delay line with linear interpolation which uses a buffer for its
10 internal memory. See also  link::Classes/BufCombN::  which uses no
11 interpolation, and  link::Classes/BufCombC::  which uses cubic
12 interpolation. Cubic interpolation is more computationally expensive
13 than linear, but more accurate.
16 classmethods::
18 method::ar
20 argument::buf
21 Buffer number.
23 argument::in
24 The input signal.
26 argument::delaytime
27 Delay time in seconds.
29 argument::decaytime
30 Time for the echoes to decay by 60 decibels. If this time is negative then the feedback coefficient will be negative, thus emphasizing only odd harmonics at an octave lower.
32 discussion::
33 Warning:: For reasons of efficiency, the effective buffer size is limited to the previous power of two. So, if 44100 samples are allocated, the maximum delay would be 32768 samples.
36 Examples::
38 code::
40 // These examples compare the variants, so that you can hear the difference in interpolation
42 // allocate buffer
43 b = Buffer.alloc(s,44100,1);
45 // Comb used as a resonator. The resonant fundamental is equal to
46 // reciprocal of the delay time.
47 { BufCombN.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
49 { BufCombL.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
51 { BufCombC.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
53 // with negative feedback:
54 { BufCombN.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
56 { BufCombL.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
58 { BufCombC.ar(b.bufnum, WhiteNoise.ar(0.01), XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
60 // used as an echo.
61 { BufCombL.ar(b.bufnum, Decay.ar(Dust.ar(1,0.5), 0.2, WhiteNoise.ar), 0.2, 3) }.play;