Bach equal temperament

The various well temperaments used in Bach's time are distinct from our equal temperament. ... Equal temperament, the modern and usually inappropriate system of tuning used in western music, is based on the twelfth root of 2. The ratio of frequencies for each semi tone is equal to the twelfth root of two.

1. Did Bach invent equal temperament?
2. What temperament did Bach use?
3. Is equal temperament out of tune?
4. What did Bach mean by well tempered?

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.

What temperament did Bach use?

In more recent times, Johann Sebastian Bach has been seen, on the one hand, as a pioneer of Equal Temperament [8] and, on the other, as a proponent of unequal Well Temperaments. In this latter regard, suggested temperaments have included those of Werckmeister [9] and Kirnberger [10].
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Is equal temperament out of tune?

One of those tunings was already known to the ancients: equal temperament. Here the poison is distributed equally through the system: The distance between each interval is mathematically the same, so each interval is equally in, and slightly out of, tune.

What did Bach mean by well tempered?

In Bach's day, the standard tuning method was called Mean-tone Temperament. ... This brings us to Bach's The Well-Tempered Clavier; that title simply means that a single keyboard is tuned in such a way that the performer can play in all 24 keys (12 major and 12 minor).