FBSineN

A non-interpolating sound generator based on the difference equations:

x[n+1] = sin(im * y[n] + fb * x[n])
y[n+1] = (a * y[n] + c) % 2pi

This uses a linear congruential function to drive the phase indexing of a sine wave. For im = 1, fb = 0, and a = 1 a normal sine wave results.

===Examples===

// default initial parameters
play { FBSineN.ar(SampleRate.ir/4) * 0.2 }

// increase feedback
play { FBSineN.ar(SampleRate.ir, 1, Line.kr(0.01, 4, 10), 1, 0.1) * 0.2 }

// increase phase multiplier
play { FBSineN.ar(SampleRate.ir, 1, 0, XLine.kr(1, 2, 10), 0.1) * 0.2 }

// modulate frequency and index multiplier
play { FBSineN.ar(LFNoise2.kr(1).mulAdd(1e4, 1e4), LFNoise2.kr(1).mulAdd(16, 17), 1, 1.005, 0.7) * 0.2 }

// randomly modulate parameters
play {
 FBSineN.ar(
   LFNoise2.kr(1).mulAdd(1e4, 1e4),
   LFNoise2.kr(1).mulAdd(32, 33),
   LFNoise2.kr(1) * 0.5,
   LFNoise2.kr(1).mulAdd(0.05, 1.05),
   LFNoise2.kr(1).mulAdd(0.3, 0.3)
 ) * 0.2
}