* 7화음의 이름
T1=T3-T5=T7 (8:10:12:15) 장3, 장7화음 Major 7th chords CM7
T1=T3-T5-T7 (20:25:30:36) 장3, 단7화음 7th chords C7
T1-T3=T5=T7 (40:48:60:75) 단3, 장7화음 minor Major 7th chords CmM7
T1-T3=T5-T7 (10:12:15:18) 단3, 단7화음 minor 7th chords Cm7
T1-T3-T5-T7 (125:150:180:216) 감7화음 Diminished 7th chords Cdim7