Designing Sound in SuperCollider/Insects

Fig 50.7: Field Cricket

(
a = {
	var modulator, mod1, mod2, mod3;
	
	// repeat time is 0.7s: equates to 1.43 Hz.
	modulator = LFSaw.ar(1.43, 1, 0.5, 0.5);
	mod2 = (modulator * 40.6 * 2pi).cos.squared;
	mod3 = modulator * 3147;
	mod3 = (mod3 * 2pi).cos + ((mod3 * 2 * 2pi).cos * 0.3);
	mod1 = ((Wrap.ar(modulator.min(0.1714) * 5.84) - 0.5).squared * (-4) + 1) * (mod2 * mod3);
	mod1 = (mod1 * 0.1)!2;
}.play;
)

// To stop: 
a.free;

Fig 50.8: Field Cricket 2

(
b = {
	var trig, seq, demand, cricket;
	
	// instead of [metro], Impulse.kr is used here. Delta t = 17 ms equates to 58.82 Hz.
	trig = Impulse.kr(58.82);
	
	// the main idea of the following line was to use an approach
	// that uses the same coefficients as described in the pd patch
	seq = Dseq(Array.fill(41, {|i| if(i<7, {(i+2)/9},{0}) }),inf);
	demand = Demand.kr(trig,0,seq);
	
	// Implementation of the pd code for pulses including amplitude grow:
	// cricket = EnvGen.ar(Env.new([0, 1, 1, 0], [0.0001, 0.0001, 0]), trig) * demand;
	
	// 2nd implementation: pure data seemed to slightly disobey its own specifications, 
	// so I analysed the waveform and came up with this:
	cricket = EnvGen.ar(Env.new([0, 1, 0], [4/44100, 0]), trig) * demand;
	
	
	cricket = OnePole.ar(cricket, exp(-2pi * (1000 * SampleDur.ir)));
	cricket = (
			// changed the Q factor of the first 3 BPFs to approximate farnells sound 
			BPF.ar(cricket, 4500 + ((0..2)*50), 300.reciprocal, 100)).sum 
			+ BPF.ar(cricket, 9000, 500.reciprocal, 42
	);		   
	cricket = ((cricket - OnePole.ar(cricket, exp(-2pi * (4000 * SampleDur.ir)))) * 0.5)!2;
}.play;
)

// To stop: 
b.free;

Fig: 50.10: Cicada with 3 call types

(
c = {
	var sig, trig, seq, freq, mul, vals;
	
	trig = Impulse.kr(0.2);
	vals = [
		[0.5, 128],
		[8,6],
		[30,3]
	];
	freq = TChoose.kr(trig, vals);
	
			
	sig = WhiteNoise.ar;
	// The one pole filters in pure data and SC differ, so I changed the coefficents 
	// a little. Also the  multiplication by 5 is not in the book, but helps to 
	// approach the audible result of Farnells patch.
	sig = (sig - OnePole.ar(sig, exp(-2pi * (8000 * SampleDur.ir))));
	sig = (sig - OnePole.ar(sig, exp(-2pi * (8000 * SampleDur.ir))));
	sig = OnePole.ar(sig, exp(-2pi * (10000 * SampleDur.ir)));
	sig = OnePole.ar(sig, exp(-2pi * (10000 * SampleDur.ir)));
	sig = sig * 5;

		
	sig = BPF.ar(sig, [7500, 5500], 40.reciprocal).sum * SinOsc.ar(500);
	sig = sig * (1 / (SinOsc.ar( freq[0], 0, freq[1] ).squared + 1));
	sig = (sig - OnePole.ar(sig, exp(-2pi * (4000 * SampleDur.ir)))) * 4.dup;
}.play;
)

// To stop: 
c.free;

Fig: 50.13 Direct signal implementation of housefly wing

The adjustable parameters in the pd patch can be controlled by the mouse movement: MouseX is controlling the wing-frequency, MouseY is controlling the wing-resonance.

(
SynthDef(\houseflyWing, { |out=0|
	var sig, downstroke, upstroke, wingFreq, wingRes;
	
	// this is already a preparation for fig 50.14 and is not described 
	// in the pure data patch on fig 50.13
	wingFreq = In.ar(10,2);
	wingRes = In.ar(20,2);

	// Also, it is prepared for some other input from a different source, 
	// to not only control the patch with the mouse movement. 
	// See also the following URL for more information about the next lines: 
	// http://supercollider.sourceforge.net/wiki/index.php/Boolean_logic_in_the_server 
	wingFreq = Select.ar(wingFreq > 0, [K2A.ar(MouseX.kr(0, 300)), wingFreq]);
	wingRes = Select.ar(wingRes > 0, [K2A.ar(MouseY.kr(3,5)), wingRes]);	

	sig = LFSaw.ar(wingFreq, 1, 0.5, 0.5);
	sig = ((sig * 0.2).min(sig * (-1) + 1)).min(sig.min(sig * (-1) + 1));
	sig = (sig * 6 - 0.5) * 2; 	
	
	downstroke = (wingRes) * sig.min(0);
	downstroke = (Wrap.ar(downstroke) * 2pi).cos * sig.min(0) * 0.5 + sig.min(0);
	upstroke = sig.max(0).cubed * 2;	
		
	sig = downstroke + upstroke;	
	sig = (sig - OnePole.ar(sig, exp(-2pi * (700 * SampleDur.ir)))).dup * 0.05;
	Out.ar(out, sig);
}).add;
x = Synth(\houseflyWing);
)

Leave it running while you run the other blocks of code below...

Fig: 50.14 Buzzing housefly

(
SynthDef(\buzzingHousefly, { 
	var beatingFreq, resonanceMod;
	
	beatingFreq = OnePole.ar(WhiteNoise.ar, exp(-2pi * (4 * SampleDur.ir)));
	beatingFreq = OnePole.ar(beatingFreq, exp(-2pi * (4 * SampleDur.ir)));
	beatingFreq = beatingFreq * 700 + 220;
		
	resonanceMod = OnePole.ar(WhiteNoise.ar, exp(-2pi * (5 * SampleDur.ir)));
	resonanceMod = OnePole.ar(resonanceMod, exp(-2pi * (5 * SampleDur.ir)));
	
	Out.ar(10, [beatingFreq, (resonanceMod * 3) + beatingFreq]);
	Out.ar(20, (resonanceMod * 40 + 5)!2 );	
}).add;
y = Synth(\buzzingHousefly);
)

// now again the housefly wings are controlled by the mouse movement.
y.free;

// To stop: 
x.free;

If the Synth(\buzzingHousefly) was executed before the Synth(\houseflyWing) you'll have to execute the following line to hear the effects of the Synth(\buzzingHousefly). This is because In.ar and Out.ar are used in this example to communicate between both patches, and when working with In.ar it is always necessary to have the Order of execution of synths on the server in mind. (see also Helpfile: Order of execution).

Synth(\buzzingHousefly, addAction: \addToHead);