rsc3/doc-schelp/HelpSource/Classes/BLowPass.scrbl

61 lines
1.5 KiB
Racket

#lang scribble/manual
@(require (for-label racket))
@title{BLowPass}
12db/oct rolloff - 2nd order resonant Low Pass Filter@section{categories}
UGens>Filters>BEQSuite
@section{related}
Classes/SOS, Classes/BLowPass4, Classes/BHiPass, Classes/BHiPass4, Classes/BPeakEQ, Classes/BLowShelf, Classes/BHiShelf, Classes/BBandPass, Classes/BBandStop, Classes/BAllPass
@section{description}
The B equalization suite is based on the Second Order Section (link::Classes/SOS::) biquad UGen.
@section{note}
Biquad coefficient calculations imply certain amount of CPU overhead. These plugin UGens contain optimizations such that the coefficients get updated only when there has been a change to one of the filter's parameters. This can cause spikes in CPU performance and should be considered when using several of these units.
::
@section{classmethods}
@section{method}
ar
@section{argument}
in
input signal to be processed.
@section{argument}
freq
cutoff frequency.
WARNING: due to the nature of its implementation frequency values close to 0 may cause glitches and/or extremely loud audio artifacts!
@section{argument}
rq
the reciprocal of Q. bandwidth / cutoffFreq.
@section{argument}
mul
@section{argument}
add
@section{method}
sc
calculate filter coefficients.
@section{examples}
@racketblock[
s.boot;
(
z = {
BLowPass.ar(
SoundIn.ar([0,1]),
MouseX.kr(10, 20000, \exponential), // cutoff freq.
MouseY.kr(0.0, 1.0, \linear), // rq
0.5); // mul
}.play
)
z.release;
::
]