Diapason may refer to: *

Diapason (interval) In music, an octave (: eighth) or perfect octave (sometimes called the diapason) is an interval between two notes, one having twice the frequency of vibration of the other. The octave relationship is a natural phenomenon that has been referre ...

, the name of the just octave in Pythagorean tuning *

Diapason (pipe organ) A flue pipe (also referred to as a ''labial'' pipe) is an organ pipe that produces sound through the vibration of air molecules, in the same manner as a recorder or a whistle, in a pipe organ. Air under pressure (called ''wind'') is driven ...

, a tonal grouping of the flue pipes of a pipe organ * ''Diapason'' (magazine), a French classical music magazine * ''The Diapason'' (magazine), an American magazine for organ builders and players * ''Diapason normal'', the official French standard of

concert pitch Concert pitch is the pitch reference to which a group of musical instruments are tuned for a performance. Concert pitch may vary from ensemble to ensemble, and has varied widely over time. The ISO defines international standard pitch as A440, ...

* ''Diapason'', a 1978 novel by Thomas Sullivan

See also