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For Students · Equal Temperament

Equal Temperament for a standing wave

Built for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition. Simulate a standing wave live below — adjust the inputs and watch it respond, right in your browser.

Equal Temperament vs Just IntonationLive

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Presets

Just intonation tunes intervals to pure whole-number frequency ratios, which sound perfectly consonant but only in one key. Equal temperament divides the octave into 12 identical steps so every key works, at the cost of every interval except the octave being slightly out of tune. The bars show that compromise in cents.

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Data Inspector

Equal-temp fifth392.0 Hz
Just fifth (3:2)392.4 Hz
Fifth error−2 cents
Major 3rd error+14 cents

Governing equation

Reading this result: The equal-tempered fifth sits at 392.0 Hz versus the pure 3:2 fifth at 392.4 Hz — only about 2 cents flat, which the ear forgives; the major third, however, runs a far more audible 14 cents sharp, the price of making every key playable.

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Frequently asked questions

Is this good for students?
Yes — this version of "Equal Temperament for a standing wave" is framed for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition.
Do I need to install anything?
No. It runs in any modern browser, free, with no account required.