tonek

tonek — A first-order recursive low-pass filter with variable frequency response.

Description

A first-order recursive low-pass filter with variable frequency response.

Syntax

kres tonek ksig, khp [, iskip]

Initialization

iskip (optional, default=0) -- initial disposition of internal data space. Since filtering incorporates a feedback loop of previous output, the initial status of the storage space used is significant. A zero value will clear the space; a non-zero value will allow previous information to remain. The default value is 0.

Performance

kres -- the output signal at control-rate.

ksig -- the input signal at control-rate.

khp -- the response curve's half-power point, in Hertz. Half power is defined as peak power / root 2.

tonek is like tone except its output is at control-rate rather than audio rate.

Examples

Here is an example of the tonek opcode. It uses the file tonek.csd.

Example 1015. Example of the tonek opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

<CsoundSynthesizer>

<CsOptions>

; Select audio/midi flags here according to platform

-odac      ;;;realtime audio out

;-iadc    ;;;uncomment -iadc if realtime audio input is needed too

; For Non-realtime ouput leave only the line below:

; -o tonek.wav -W ;;; for file output any platform

</CsOptions>

<CsInstruments>



sr = 44100

ksmps = 32

nchnls = 2

0dbfs  = 1



gisin ftgen 0, 0, 2^10, 10, 1



instr 1



ksig	randomh	400, 1800, 150

aout	poscil	.2, 100+ksig, gisin

	outs	aout, aout

endin



instr 2



ksig	randomh	400, 1800, 150

khp	line	1, p3, 100	;vary high-pass

ksig	tonek	ksig, khp

aout	poscil	.2, 100+ksig, gisin

	outs	aout, aout

endin



</CsInstruments>

<CsScore>



i 1 0 5

i 2 5.5 5

e

</CsScore>

</CsoundSynthesizer>


See Also

areson, aresonk, atone, atonek, port, portk, reson, resonk, tone

Credits

Author: Robin Whittle
Australia
May 1997