Perfect 5th
7 semitones — the foundation of musical movement
Degree 5Solfège: soNotation: P5
The perfect 5th is an interval of 7 semitones — the most consonant interval after the octave, appearing on the 3rd harmonic (3:2). It is the beginning of musical movement via the circle of 5ths, and the backbone of the most important triads, tetrads, pentatonics, and every popular mode.