Musical note commonly), a double sharp sign on a key signature with a single sharp indicates only a double sharp, not a triple sharp. Assuming enharmonicity, many accidentals will create equivalences between pitches that are written differently. For instance, raising the note B to B is equal to the note C. Assuming all such equivalences, the complete chromatic scale adds five additional pitch classes to the original seven lettered notes for a total of 12 (the 13th note completing the octave), each separated by a half-step. Notes that belong to the diatonic scale relevant in the context are sometimes called "diatonic notes";
Blues scale G, B. The latter is the hexatonic scale (top). The heptatonic, or seven-note, conception of the blues scale is as a diatonic scale (a major scale) with lowered third, fifth, and seventh degrees Blues practice is derived from the "conjunction of 'African scales' and the diatonic western scales". \override Score.TimeSignature #'stencil = ##f \relative c' { </score> Steven Smith argues that, "to assign blue notes to a 'blues scale' is a momentous mistake, then, after all, unless we alter the meaning of 'scale'". An essentially nine-note blues scale is defined by Benward and Saker as a chromatic variation of the