Minor third
A minor third in just intonation most often corresponds to a pitch ratio of 6:5 (or 1:1.2), or various other ratios. while in an equal tempered tuning, a minor third is equal to three semitones, a ratio of 1:23/12 (approximately 1:1.189), or 300 cents, 15.641 cents smaller.
The minor third is considered the most consonant interval after the unison, octave, perfect fifth, perfect fourth, major third, and minor sixth.
Augmented second
An augmented second is a musical interval larger than a major second. It is thus either a quarter tone sharp from the major as is found in the quarter tone scale and Arab music and tuning, or a minor second larger, as found in twelve tone equal temperament, and thus enharmonically equivalent to a minor third.
Augmented seconds occur in many scales, most importantly the harmonic minor and its various modes. They also occur in the various "gypsy minor" scales (which consist almost entirely of augmented and minor seconds). An example of the augmented second is in the A harmonic minor scale between F and G#, where it serves to allow chords in a minor key to follow the same rules of cadence observed in major keys where the V chord is "dominant" (that is, contains a major triad plus a minor seventh).
See also
| Minor third | ||||||||
|---|---|---|---|---|---|---|---|---|
| # semitones | Interval class | # cents in equal temperament | Most common diatonic name | Comparable just interval | # cents in just interval | Just interval vs. equal-tempered interval | ||
| 3 | 3 | 300 | minor third | 6:5 | 316 | 16 cents larger | ||
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