Minor Seventh

Count letter names inclusively: C, D, E, F, G, A, B. That makes the interval a seventh.

C to B flat covers ten semitones, which makes it minor. C to B covers eleven and is a major seventh.

C to A sharp uses the same equal-tempered piano keys, but the letter count reaches A. It is an augmented sixth.

Invert C-B flat by moving C above B flat. The result is B flat-C, a major second.

Interval numbers under inversion add to nine: 7 plus 2. Minor quality becomes major.

This gives you a reliable check and connects the wide interval to a familiar whole-step distance.

An ascending minor seventh is a large leap, such as C4 to B-flat4. A descending version reverses the direction.

Practice C-B flat-C so the upper note is heard two semitones below the octave. Then transpose the pattern to F-E flat-F and A-G-A.

Large leaps often need preparation or a following step in the opposite direction, but melody style and register determine the actual phrase.

Natural minor contains a minor seventh above its tonic. C natural minor includes B flat.

Mixolydian also contains flat 7 while keeping a major third. C Mixolydian is C-D-E-F-G-A-B flat.

Dorian and Phrygian contain a minor seventh as well. The interval alone does not identify the complete scale.

C7 contains C-E-G-B flat. Its root-to-seventh interval is C-B flat.

The directional tension comes especially from the tritone E-B flat. In a common resolution to F major, E rises to F and B flat falls to A.

The minor seventh contributes to the chord type, while the relationship between third and seventh supplies the characteristic voice leading.

Cm7 contains C-E flat-G-B flat. It shares C, G and B flat with C7, but E flat replaces E.

E flat-B flat is a perfect fifth, so the chord does not contain the E-B-flat tritone found in C7.

Cm7 can function as a tonic sonority, as ii in B-flat major or in other roles. The progression determines whether it sounds settled or expects movement.

An interval names the distance between two notes. A chord adds more notes, and a key gives those notes harmonic roles.

C-B flat remains a minor seventh in C7, Cm7 and Csus7. The third and the surrounding progression change how the whole chord behaves.

Identify interval, chord quality and function as three separate layers.

The major sixth is one semitone narrower. The major seventh is one semitone wider.

An augmented sixth can use the same piano keys in equal temperament but has a different spelling and normally different voice leading.

In chord symbols, C7 and Cm7 both contain a minor seventh. The letter m in Cm7 describes the triad, not the seventh.

Equal temperament sets the minor seventh at 1,000 cents.

Several just ratios can represent a minor seventh in different contexts. A 9:5 interval is about 1,018 cents, while 16:9 is about 996 cents.

Players with flexible pitch may adjust sustained notes according to chord function. The written name stays the same while tuning varies.

Compare C-A, C-B flat, C-B and C-C. Say major sixth, minor seventh, major seventh and octave.

Invert C-B flat to B flat-C and identify the major second.

Then play C7 and Cm7. Follow E changing to E flat while C, G and B flat remain fixed.