Minor 7th chords
The minor 7th chord (abbreviated m7 in chord names) is a four note chord, but due to the characteristics of the guitar the chords can involve four to six notes (in some cases with duplicated notes). The minor 7th is similar to the dominant 7th, but is distinguished with its minor third.
The chord is built by a root, a minor third, a fifth and a minor seventh. There are many ways to play these chords. Below you can see m7 chords in mostly open position presented and by scrolling down further you could also see minor seventh barre chords.
Open minor 7th chords
The dots indicate there to place your fingers. X means that the string shouldn't be played at all and the numbers indicate frets (0 means that the string should be played open).
To look closer at this certain chord type we can take Am7 as an example. Am7 consists of four notes: A, C, E and G. Played as an open chord on the guitar it includes the following notes (from 5th to 1st string): A, E, G, C and E. The E note is duplicated, not because it's the most important note, but due to the circumstance of the instrument and how it's tuned.
Movable barre shapes for minor 7th chords
These two shapes can be used for all m7 chords and the root note is the bass notes on the 6th and 5th strings respectively. If the shapes are moved one step further up the neck, the chords are G#m7 and Cm7 respectively.
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