In
music, flat means "lower in pitch." More specifically, in
music notation, flat means "lower in
pitch by a
semitone (half step)," and has an associated symbol , which looks somewhat like a lowercase "b". The Unicode character '' (U+266D) can be used to display a flat sign.Under twelve tone
equal temperament, C flat for instance is the same as, or
enharmonically equivalent to, B
natural, and G flat is the same as F
sharp. Note that in any other tuning system, such enharmonic equivalences in general do not exist.Double flats also exist, which look like and lower a note by two semitones, or a whole step. Less often (in for instance
microtonal music notation) one will encounter half, or three-quarter, or otherwise altered flats. The Unicode character '𝄫' (U+1D12B) represents the double flat sign.
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