E is the third note of the C major scale, and mi in fixed-do solfège. It has enharmonic equivalents of F♭ (which is by definition a diatonic semitone above E♭) and D, amongst others.
When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of Middle E (E4) is approximately 329.628 Hz. See pitch (music) for a discussion of historical variations in frequency.
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. 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.
The prelude to Richard Wagner's Das Rheingold is a famous piece of drone music that begin with a low E flat and builds to more and more elaborate figurations of the chord of E flat major. It is used in this opera to portray the motion of the river Rhine.
Beethoven's Piano Concerto No. 5 (also known as The Emperor) is another well-known piece set in the key of E flat major.
Jimi Hendrix's Voodoo Chile is another well-known popular music piece commonly performed in E flat major.
F is a musical note, the fourth above C. It is also known as fa in fixed-do solfège.
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.