Harmony note (in this case B, D and F) provide the harmony. In the musical scale, there are twelve pitches. Each pitch is referred to as a "degree" of the scale. The names A, B, C, D, E, F, and G are insignificant. The intervals, however, are not. Here is an example: As can be seen, no note always corresponds to a certain degree of the scale. The "tonic", or 1st-degree note, can be any of the 12 notes (pitch classes) of the chromatic scale. All the other notes fall into place. For example, when C is the tonic, the fourth
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,