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";
Jazz scale and B are blue notes. The harmonic minor scale is also of value to many improvisors, as it provides an alternative color for many common chords and chord progressions. An example is C-D-E-F-G-A-B-C. The C harmonic minor scale can be used on the chords of a piece in C minor, especially on the minor ii V7 i chord progression. One of the most common uses of the harmonic minor scale is its fifth mode, which is a frequently-heard sound over dominant chords. The altered dominant scale, also loosely called the altered scale, is so named because all the scale members