Quarter-comma meantone each kind, a perfect fifth of meantone contains four diatonic and three chromatic semitones, and an octave seven diatonic and five chromatic semitones, it follows that: Thus, in Pythagorean tuning, where sequences of just fifths (frequency ratio 3:2) and octaves are used to produce the other intervals, a whole tone is and a major third is An interval of a seventeenth, consisting of sixteen diatonic and twelve chromatic semitones, such as the interval from D to F, can be equivalently obtained using either This large interval of a seventeenth contains staff positions. In Pythagorean tuning, the size of a seventeenth
Pitch interval Thus the ordered pitch class interval, i<"x", "y">, may be defined as: Ascending intervals are indicated by a positive value, and descending intervals by a negative one. Pitch interval In musical set theory, a pitch interval (PI or ip) is the number of semitones that separates one pitch from another, upward or downward. They are notated as follows: For example C4 to D4 is 3 semitones: While C4 to D5 is 15 semitones: However, under octave equivalence these are the same pitches (D4 & D5, ), thus the #Pitch-interval class may be used. In musical set theory, a pitch-interval class