MBLOWHOLE

It was originally adapted from Perry Cook and Gary Scavone's STK, the Synthesis ToolKit for doing amazing physical model stuff.

Here's what Perry and Gary say about "BlowHole":

This class is based on the clarinet model, with the addition of a two-port register hole and a three-port dynamic tonehole implementation, as discussed by Scavone and Cook (1998).

In this implementation, the distances between the reed/register hole and tonehole/bell are fixed. As a result, both the tonehole and register hole will have variable influence on the playing frequency, which is dependent on the length of the air column. In addition, the highest playing freqeuency is limited by these fixed lengths.

/* MBLOWHOLE - the "BlowHole" physical model instrument in
        Perry Cook/Gary Scavone's "stk" (synthesis tookkit).

   p0 = output start time
   p1 = duration
   p2 = amplitude multiplier
   p3 = frequency (Hz)
   p4 = noise gain (0.0-1.0)
   p5 = max pressure (0.0-1.0)
   p6 = reed stiffness (0.0-1.0)
   p7 = Tonehole state (1 == "open"; 0 == "closed")
   p8 = Register vent state (1 == "open"; 0 == "closed")
   p9 = percent of signal to left output channel [optional, default is .5]

   Assumes function table 1 is breathPressure (amplitude) curve for the note.
   Or you can just call setline. If no setline or function table 1, uses
   flat curve.
*/

rtsetparams(44100, 2)
load("MBLOWHOLE")

makegen(1, 24, 1000, 0,1, 2,0)
MBLOWHOLE(0, 3.5, 20000.0, 414.0, 0.2, 0.7, 0.5, 1, 1)
MBLOWHOLE(4, 3.5, 20000.0, 414.0, 0.2, 0.7, 0.5, 0, 1)