Stochastic granular synthesis.

in RTcmix/insts/std/MARAGRAN

quick syntax:

SGRANR(outsk, dur, amp, rate, p4-7: ratevar, p8-11: duration, p12-15: location, p16-19: transposition[, grainlayers (not used), seed])

Param Field Parameter Units Dynamic Optional Notes
p0 output start time seconds no no  
p1 duration seconds no no  
p2 amplitude multiplier relative multiplier of input signal no no  
p3 grain rate seconds no no  
p4-7 rate variance between 0.0 and 1.0 no no the % variation in rate - 100% being the rate
p8-11 duration values seconds no no  
p12-15 location values 0-1 stereo; 0.5 is middle no no  
p16-19 pitch values Hz no no  
p20 grainlayers - no yes default: 0
p21 random number seed - no yes default: 0

Because this instrument has not been updated for pfield control, the older makegen control envelope sysystem should be used:

Assumes function table 1 is the amplitude envelope function table 2 is the synthesis waveform, function table 3 is grain amplitude envelope

Parameters after the [bracket] are optional and default to 0 unless otherwise noted.

Author: Mara Helmuth (mara dot helmuth at uc dot edu)

SGRANR does stochastic granular synthesis. It’s a fairly powerful instrument, with lots of snazzy gen-envelope controls to produce evolving granular textures. To best understand the concepts behind the design of this instrument, see Mara Helmth’s papers on the use of these techniques.

It was originally adapted from the older sgran Cmix instrument, also written by Mara.

Usage Notes

At present the setting of the buffer size in rtsetparams appears to have a significant effect on the output of this instrument.

SGRANR produces stereo output.

Sample Scores

very basic:

   rtsetparams(44100, 2)

   makegen(1, 7, 1000, 1, 950, 1, 50, 0)
   makegen(2, 10, 1000, 1)
   makegen(3, 7, 1000, 0, 500, 1, 500, 0)

   start = 0.0
   SGRANR(start, 9.7, 20000, 
   /* grain rate, ratevar values (must be positive, 
      % until next grain possible displacement): */
   .1, 0.1, 0.1, 0.1, 1.0,
   /* duration values: */
   /* location values: */
   /* pitch values: */
   /* granlyrs, seed */

See Also