Minor seventh chord
In music, a minor seventh chord is any nondominant seventh chord where the "third" note is a minor third above the root.
Most typically, minor seventh chord refers to where the "seventh" note is a minor seventh above the root (a fifth above the third note). This is more precisely known as a minor/minor seventh chord, and it can be represented as either as m7 or -7, or in integer notation, {0, 3, 7, 10}. In a natural minor scale, this chord is on the tonic, subdominant, and dominant[1] degrees. In a harmonic minor scale, this chord is on the subdominant[1] degrees. In an ascending melodic minor scale, this chord is on the supertonic[1] degree. In a major scale, this chord is on the second (supertonic seventh), third (mediant) or sixth (submediant)[2] degrees. For instance the ii7 in the ii-V-I turnaround.
When the seventh note is a major seventh above the root, it is called a minor/major seventh chord. Its harmonic function is similar to that of a "normal" minor seventh, as is the minor seven flat five or half-diminished chord - but in each case, the altered tone (seventh or fifth, respectively) creates a different feel which is exploited in modulations and to utilize leading-tones.
Minor/minor seventh chord table
The just minor seventh chord is tuned in the ratios 10:12:15:18.[3] 
Play (help·info) This may be found on iii, vi, and vii.[4] Another tuning may be in the ratios 48:40:32:27.[5] Play (help·info)
Sources
- ↑ 1.0 1.1 1.2 1.3 Benward & Saker (2003). Music: In Theory and Practice, Vol. I, p.230. Seventh Edition. ISBN 978-0-07-294262-0.
- ↑ Benward & Saker (2003), p.229.
- ↑ David Wright (2009). Mathematics and Music, p.141. ISBN 978-0-8218-4873-9.
- ↑ Wright, David (2009). Mathematics and Music, p.140-41. ISBN 978-0-8218-4873-9.
- ↑ François-Joseph Fétis and Mary I. Arlin (1994). Esquisse de l'histoire de l'harmonie, p.97n55. ISBN 0-945193-51-3.