Major scale will generally reflect the accidentals in the corresponding major scale. For instance, if a piece of music is in E major, then the seven pitches in the E major scale (E, F, G, A, B, C and D) are considered diatonic pitches, and the other five pitches (E, F/G, A, B, and C/D) are considered chromatic pitches. In this case, the key signature will have three flats (B, E, and A). The figure below shows all 12 relative major and minor keys, with major keys on the outside and minor keys on the inside arranged around the circle of fifths.
Tetratonic scale the note A occurs twice in this pattern, there are only four pitches in all. Tetratonic scale A tetratonic scale is a musical scale or mode with four notes per octave. This is in contrast to a heptatonic (seven-note) scale such as the major scale and minor scale, or a dodecatonic (chromatic 12-note ) scale, both common in modern Western music. Tetratonic scales are not common in modern art music, and are generally associated with prehistoric music. Tetratonic scales were common among the Plains Indians, though less common than the pentatonic scale. Amongst the Arapaho, Blackfoot, Crow, Omaha, Kiowa, Pawnee,