An equal temperament is a
musical temperament. It is a system of
tuning in which every pair of adjacent notes has an identical
frequency ratio. Equal temperaments are often intended to approximate some form of
just intonation. In such cases, an
interval - usually the
octave - is divided into a series of equal
steps (equal frequency ratios). For modern
Western music, the most common tuning system is twelve-tone equal temperament, sometimes abbreviated as 12-TET, which divides the octave into 12 equal parts. This system is usually tuned relative to a standard pitch of
440 Hz.
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