GENtanh
"tanh" — Generate a table with values on the tanh function.
Initialization
size -- number of points in the table. Must be a power of 2 or power-of-2 plus 1 (see f statement).
start, end -- first and last value to be stored; the GEN draws a curve that goes from start to end: tanh(start) .... tanh(end). The points stored are uniformly spaced between these to the table size
rescale -- if not zero the table is not rescaled
Examples
Here is a simple example of the GENtanh routine. It uses the file gentanh.csd.
Example 1131. Example of the GENtanh routine.
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 gentanh.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 2 0dbfs = 1 instr 1 aswp linseg 0.01, p3*.5, .49, p3*.5, 0.01 ;index sweep function aindex poscil aswp, 110, 1 ;sound to waveshape atable tablei aindex, p4, 1, .5 ;waveshape index aenv linen 0.8, .01, p3, .02 ;amplitude envelope asig = (atable*aenv)*p5 ;impose envelope and scale asig dcblock2 asig ;get rid of DC outs asig, asig endin </CsInstruments> <CsScore> f 1 0 8192 10 1 ;sine wave f 2 0 8192 "tanh" -100 100 0 ;symmetrical transfer fuction f 3 0 8192 "tanh" -10 10 0 ;symmetrical f 4 0 8192 "tanh" 0 10 0 ;not symmetrical i1 0 3 2 1 i1 + 3 3 1 i1 + 3 4 2 e </CsScore> </CsoundSynthesizer>
These are the diagrams of the waveforms of the GENtanh routines, as used in the example:
f 2 0 8192 "tanh" -100 100 0 - lots of distortion
f 3 0 8192 "tanh" -10 10 0 - less distortion than f2
f 4 0 8192 "tanh" -10 15 0
See Also
More information on this routine: http://www.csoundjournal.com/issue11/distortionSynthesis.html, written by Victor Lazzarini