E♭ (musical note)
E♭ (E-flat) or mi bémol is the fourth semitone of the solfege.
It lies a diatonic semitone above D and a chromatic semitone below E, thus being enharmonic to D♯ (D-sharp) or Re Dièse. In equal temperament it is also enharmonic with F
. However, in some temperaments, D-sharp is not the same as E-flat. E-flat is a perfect fifth below B♭, whereas D-sharp is a major third above B.
When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of the E♭ above middle C (or E♭4) is approximately 311.127 Hz. See pitch (music) for a discussion of historical variations in frequency.
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