(Consonance, Dissonance) Agreeable (satisfactory) or disagreeable (unsatisfactory) effects created by chords on the listener. Chords consisting of consonant intervals (octave, perfect fifth, perfect fourth, third, sixth) are called consonant and those containing dissonant intervals (second, seventh, ninth, augmented intervals, etc) are dissonant chords. The triadic chords and their inversions are consonant, whereas, all others including augmented sixth and diminished seventh chords are dissonant.