Accidental (music) felt it was obvious that the accidental should continue. The older practice continued in use well into the 18th century by many composers, notably Johann Sebastian Bach. The newer convention did not achieve general currency until early in the 19th century. Accidental (music) In music, an accidental is a note of a pitch (or pitch class) that is not a member of the scale or mode indicated by the most recently applied key signature. In musical notation, the sharp (), flat (), and natural () symbols, among others, mark such notes—and those symbols are also called accidentals. In the measure
Off-key note in jazz. The opposite of off-key is on-key or in-key, which suggests that there is a well defined keynote, or reference pitch. This does not necessarily have to be an absolute pitch but rather one that is relative for at least the duration of a song. A song is usually in a certain key, which is usually the note that the song ends on, and is the base frequency around which it resolves to at the end. The base-frequency is usually called the harmonic or key center. Being on-key presumes that there is a key center frequency around which