Pitch interval
In musical set theory, there are four kinds of interval: Ordered pitch interval Unordered pitch interval Ordered pitch-class interval Unordered pitch-class interval == Pitch intervals == === Ordered pitch interval === The ordered pitch interval is the number of semitones that separates one pitch from another, upward or downward. It is thus more specific than the unordered pitch interval in that it represents the directionality of the interval.