more on waveforms

All sound is made of waveforms.

They're measured in amplitude vs. time graphs, so they look like those trig graphs people do in highschool.

The basic one is called a sine wave.

(So trig was useful after all!)

It looks like this.

Of all waves, the sine is the simplest.

When moving harmonically, it makes the purest tones.

It can only move at a certain Hz, because it is so simple

Obviously.

All other waves can be made from it.

These others are made through combinations of the sine wave and other harmonics.

Because of varying combinations, they can move at more than just one Hz level.

For example, a sawtooth wave is made like this.

The more harmonics you add, the closer it gets to a real sawtooth.

Other waves follow similar steps to reach.

It's all known as the FOURIER THEOREM.

This is what it states formally.

A MATHEMATICAL THEOREM STATING THAT A PERIODIC FUNCTION F(X) WHICH IS REASONABLY CONTINUOUS MAY BE EXPRESSED AS THE SUM OF A SERIES OF SINE OR COSINE TERMS (CALLED THE FOURIER SERIES), EACH OF WHICH HAS SPECIFIC AMPLITUDE AND PHASE COEFFICIENTS KNOWN AS FOURIER COEFFICIENTS.

Pictures explain it better.

All can be made from variations of the sine wave.

Just think of the sine as a LEGO.

Put LEGOs on each other one way, and you have a little horse.

Stack them another way and you have a little AK-47.

Although that might not be such a good idea.

Psychologists don't really like that.

more on waveforms

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