An interesting physical phonemenon, indeed.

Nope, this is quite different from binaural beats. I’ve learned quite a lot about the concept after writing this post, and frankly, I’m quite embarrassed to keep this here because it is kinda naive considering the great works I’ve discovered that exploits this phenomenon. It still points to some limits of the system though…

The low frequency sound here is actually emitted by your very own ears, and can even be recorded with a mike (if placed close to your ear canal)! It’s called otoacoustic emission, if you want to search about it.

Interesting article. Thanks for sharing it.

this is one of my favorite irritating sounds, you can make even harmony with this.

try this lullaby

(
SynthDef(\diffalea, { arg freq = 220, gate = 1, amp = 1, lowFreq = 1000, hiFreq = 1500;
var freq1 = Rand(lowFreq, hiFreq);
var freq2 = freq1 – freq;
var env = EnvGen.kr(Env.asr(0.01, 1, 0.01, 1, ‘linear’), gate, doneAction: 2);
Out.ar(0, Mix(SinOsc.ar([freq1, freq2], 0.5pi.rand, mul:amp*env))!2);
}).memStore;

~freqs = [48, 50, 52, 48, 48, 50, 52, 48, 52, 53, 55, 52, 53, 55, 55, 57, 55, 53, 52, 48, 55, 57, 55, 53, 52, 48, 50, 44, 48, 50, 48, 50].midicps;

~duras = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 0.5, 0.5, 0.5, 0.5, 1, 1, 0.5, 0.5, 0.5, 0.5, 1, 1, 1, 1, 2, 1, 1, 2];
)

(
Pbind(
\instrument, \diffalea,
\lowFreq, [2200, 1200, 3200], \hiFreq, [2400, 1400, 3400],
\freq, Pseq(~freqs+[0, 0, 0], inf),
\dur, Pseq(~duras+[0, 0, 0], inf),
\legato, 1,
\strum, 8
).play(TempoClock(1));
)

Cheers!

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