Key signature A minor as each accidental may be notated explicitly as required, or the piece may be modal or atonal. An example is Bartók's Piano Sonata, which has no fixed key and is highly chromatic. If not bound by common practice conventions, microtones can also be notated in a key signature; which microtonal symbols are used depends on the system. The common practice period conventions are so firmly established that some musical notation programs have been unable to show nonstandard key signatures until recently. The use of a one-flat signature developed in the Medieval period, but signatures with more than one
Key signature Prez features two voice parts with two flats, one part with three flats, and one part with four flats. Baroque music written in minor keys often was written with a key signature with fewer flats than we now associate with their keys; for example, movements in C minor often had only two flats (because the A would frequently have to be sharpened to A in the ascending melodic minor scale, as would the B). Key signature In musical notation, a key signature is a set of sharp (), flat (), and rarely, natural () symbols placed together on the staff.