89 lines
2.2 KiB
Racket
89 lines
2.2 KiB
Racket
#lang scribble/manual
|
|
@(require (for-label racket))
|
|
|
|
@title{CombL}
|
|
Comb delay line with linear interpolation.@section{related}
|
|
Classes/CombC, Classes/CombN, Classes/BufCombL
|
|
@section{categories}
|
|
UGens>Delays
|
|
|
|
|
|
@section{description}
|
|
|
|
|
|
Comb delay line with linear interpolation. See also link::Classes/CombN::
|
|
which uses no interpolation, and link::Classes/CombC:: which uses cubic
|
|
interpolation. Cubic interpolation is more computationally expensive
|
|
than linear, but more accurate.
|
|
|
|
The feedback coefficient is given by the equation
|
|
@racketblock[ fb == 0.001 ** (delay / decay.abs) * decay.sign :: where 0.001 is -60 dBFS.
|
|
|
|
]
|
|
@section{classmethods}
|
|
|
|
|
|
@section{method}
|
|
ar, kr
|
|
|
|
@section{argument}
|
|
in
|
|
The input signal.
|
|
|
|
@section{argument}
|
|
maxdelaytime
|
|
The maximum delay time in seconds. Used to initialize the delay buffer size.
|
|
|
|
@section{argument}
|
|
delaytime
|
|
Delay time in seconds.
|
|
|
|
@section{argument}
|
|
decaytime
|
|
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.
|
|
|
|
Infinite decay times are permitted. A decay time of
|
|
@racketblock[inf:: leads to a feedback coefficient of 1, and a decay time of ]
|
|
|
|
@racketblock[-inf:: leads to a feedback coefficient of -1.
|
|
|
|
]
|
|
@section{argument}
|
|
mul
|
|
Output will be multiplied by this value.
|
|
|
|
@section{argument}
|
|
add
|
|
This value will be added to the output.
|
|
|
|
@section{Examples}
|
|
|
|
|
|
|
|
@racketblock[
|
|
|
|
// These examples compare the variants, so that you can hear the difference in interpolation
|
|
|
|
// Comb used as a resonator. The resonant fundamental is equal to
|
|
// reciprocal of the delay time.
|
|
{ CombN.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
|
|
|
|
{ CombL.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
|
|
|
|
{ CombC.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), 0.2) }.play;
|
|
|
|
// with negative feedback:
|
|
{ CombN.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
|
|
|
|
{ CombL.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
|
|
|
|
{ CombC.ar(WhiteNoise.ar(0.01), 0.01, XLine.kr(0.0001, 0.01, 20), -0.2) }.play;
|
|
|
|
// used as an echo.
|
|
{ CombL.ar(Decay.ar(Dust.ar(1,0.5), 0.2, WhiteNoise.ar), 0.2, 0.2, 3) }.play;
|
|
|
|
::
|
|
|
|
]
|
|
|
|
|