Key signature key signatures showing sharps or flats on both octaves for notes which fall within the staff. An accidental is an exception to the key signature, applying only to the measure and octave in which it appears. Although a key signature may be written using any combination of sharp and flat symbols, the most common series of thirteen homogeneous key signatures—ranging from six flats to six sharps, with each successive flat or sharp placed on the note a perfect fifth below or above, respectively, the previous one—is assumed in much of this article. A piece scored using a single diatonic key
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.