Minor + 7 chords

This is a fairly modern chord that you won't find in old fashioned sing along tunes, traditional folk music and other simpler harmonic styles.

You find it rather strong, somewhat dissonant sound most often in jazz.

It is seen as 'passing' chord in a series of minor chords ith one moving voic.

This chord is formed by adding the note of a maj 7th above the root to a minor triad.

Cm+7
C Eb G B

1 b3 5 7

This chord is unusual than the others.
It is notated as: min(maj7)

As a spicy expansion of a minor traid, the m+7 chord is sometimes used by jazz musicians to add color to a plainer chord.

When speficially notated on a chord chart, one of its most common uses is in this familiar sounding pattern:
Am Am+7 Am7 Am6

LH bass: A G# G F#


OR

Em Em+7 Em7 Am7

LH bass: E D# D A


Dm Dm+7 Gm7 A7

LH bass: D C#