D (musical note)

D is a musical note a whole tone above C, and is known as Re within the fixed-Do solfege system. An enharmonic note is C, which is a diatonic semitone below D♯.

When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of middle D (D₄) is approximately 293.665 Hz. See pitch for a discussion of historical variations in frequency.

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