Equal temperament history

Equal temperament tuning was widely adopted in France and Germany by the late 18th century and in England by the 19th. ... Earlier European tuning systems—such as meantone temperament and just intonation—were “cyclic” systems, in which given intervals were calculated by adding together other “pure” intervals.

1. Did Bach invent equal temperament?
2. Who invented 12 tone equal temperament?
3. Did Beethoven use equal temperament?
4. Is equal temperament a form of just temperament?

Did Bach invent equal temperament?

Bach did not use equal temperament. In fact, in his day there was no way to tune strings to equal temperament, because there were no devices to measure frequency.

Who invented 12 tone equal temperament?

Simon Stevin was the first to develop 12-TET based on the twelfth root of two, which he described in Van De Spiegheling der singconst (ca. 1605), published posthumously nearly three centuries later in 1884.

Did Beethoven use equal temperament?

UNEQUAL TEMPERAMENT

Neither did Mozart nor Beethoven or any of their contemporaries. They used unequal temperaments — also known as, you guessed it, Well-tempered. In the Well-Tempered Clavier, Bach celebrated unequal tempered tuning, not today's equal tempered tuning.

Is equal temperament a form of just temperament?

It is a compromise tuning scheme. The equal tempered system uses a constant frequency multiple between the notes of the chromatic scale.
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Just vs Equal Temperament (and related topics)