Howtosignalprocessing
What pitch is g4?
As such it is the dominant, a perfect fifth above C or perfect fourth below C. When calculated in equal temperament with a reference of A above middle C as 440 Hz, the frequency of middle G (G4) note is approximately 391.995 Hz. See pitch for a discussion of historical variations in frequency.
What is the value of a note?
In music notation, a note value indicates the relative duration of a note, using the texture or shape of the notehead, the presence or absence of a stem, and the presence or absence of flags/beams/hooks/tails. Unmodified note values are fractional powers of two, for example one, one-half, one fourth, etc.
