D♭ (musical note)
Musical note / From Wikipedia, the free encyclopedia
D♭ (D-flat) is a musical note lying a diatonic semitone above C and a chromatic semitone below D. It is thus enharmonic to C♯. In the French solfège it is known as re bémol. It is the second semitone of the solfège.
When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of middle D♭ (or D♭4) is approximately 277.183 Hz.[1] See pitch (music) for a discussion of historical variations in frequency.