E♯ (musical note)

F is a musical note, the fourth above C. It is also known as fa in fixed-do solfège. It has enharmonic equivalents of E♯ and G, amongst others.

When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of Middle F (F4) is approximately 349.228 Hz. See pitch (music) for a discussion of historical variations in frequency.

E♯ is a common enharmonic equivalent of F, but is not regarded as the same note. E♯ is commonly found before F♯ in the same measure in pieces where F♯ is in the key signature, in order to represent a diatonic, rather than a chromatic semitone; writing an F♮ with a following F♯ is regarded as a chromatic alteration of one scale degree.

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