Key signature sometimes called "standard key signatures". Other scales are written either with a standard key signature and use accidental as required, or with a nonstandard key signature. Examples of the latter include the E (right hand), and F and G (left hand) used for the E diminished (E octatonic) scale in Bartók's "Crossed Hands" (no. 99, vol. 4, "Mikrokosmos"), or the B, E and F used for the D Phrygian dominant scale in Frederic Rzewski's "God to a Hungry Child". The absence of a key signature does not always mean that the music is in the key of C major /
Off-key Off-key Off-key is musical content that is not at the expected frequency or pitch period, either with respect to some absolute reference frequency, or in a ratiometric sense (i.e. through removal of exactly one degree of freedom, such as the frequency of a keynote), or pitch intervals not well-defined in the ratio of small whole numbers. The term may also refer to a person or situation being out of step with what is considered normal or appropriate. A single note deliberately played or sung off-key can be called an "off-note". It is sometimes used the same way as a blue