Drop2 Voicings: guitar chords chart — 7th chords (aka 'four-part' chords)
These Drop2 guitar chords chart will help you play all five types of seventh chord, on the fretboard. Click on the numbers below the image to display major seventh (M7) chords, minor seventh (m7) chords, dominant (7) chords, half-diminished (b5m7) chords and diminished seventh (dim7) chords, in that order.
Seventh chords (aka 'four-part chords') are built by adding an additional third on top of a triad: brush up on your guitar triads before you start with this guitar chords chart!
The interval structure of seventh chords
What makes each of the five different kinds of seventh chord unique is their interval structure. This will be much easier to understand once you understand the interval structure of triads, so I will insist again: go play those first!
Just like their three-part counterparts, all four-part chords start on a root, up from which the rest of the chord structure is built. The next note is the third, next comes the fifth, and then an additional seventh up at the very top.
(major third + minor third + major third = major seventh)
OR: major triad (spanning a perfect fifth) + major third
(minor third + major third + minor third = minor seventh)
OR: minor triad (spanning a perfect fifth) + minor third
(major third + minor third + minor third = minor seventh)
OR: major triad (spanning a perfect fifth) + minor third
(minor third + minor third + major third = minor seventh)
OR: diminished triad (spanning a diminished fifth) + major third
(minor third + minor third + minor third = diminished seventh)
OR: diminished triad (spanning a diminished fifth) + minor third
You may have noticed the funky moniker in the headline: 'Drop2 Voicings: guitar chords chart'... what this means is:
Unlike guitar triads, four-part chords cannot be played in closed position on the fretboard. A closed-position voicing of a chord is one where no gaps are left between any pair of chord tones: in the case of triads and 7th chords, closed-position voicings all fit within a single octave. If you try to play 7th chords in closed position on the fretboard, you will inevitably find that two out of the four chord-tones fall on a single string... no way around that!
This means that some other solution to the 'two-notes-on-a-string problem' must be found. The solution is simple enough, as shown in the guitar chords chart above. We'll use a M7 chord on C, in root position, as our example. The chord tones are: C, E, G, B. If you start your M7 chord on the eighth fret of string six, you will soon realize that C and E both fall on string 6. Since you're playing your M7 chord in root position, the chord tone that must go from string 6 is E. And the only way is to shift it up an octave. Since E is the second note up from the root, we say that we're 'dropping' it up an octave. Hence 'Drop2'.
If the naming were up to me, I would have named it 'raise 2', or something slightly more congruent. But the term Drop2 is in common usage, so let's stick to it for convenience' sake.
You can further proceed to 'drop' the third chord tone up an octave —G, in our example. This would yield what is known as a Drop3 voicing. You can work out the logic to that name yourself!
Drop2 guitar chords chart: inversions
Just as with triads, Drop2 voicings of four-part chords can be inverted. In the case of triads, there is 'root position', 'first inversion' and 'second inversion'. Seventh chords, obviously, have one additional position. You can play them in root position (aka '1st position'), with 1 at the bottom; first inversion (aka '2nd position'), with 3 at the bottom; second inversion (aka '3d position'), with 5 at the bottom; and third inversion (aka '4th position'), with 7 as its lowest note.
You'll find the root position of each of the five types of 7th chords in the first row of the guitar chords chart above: this position always has the root, '1', at the bottom, followed by 5, 7 and 3. Each subsequent row shows the chord's inversions, in order.
Just as with triads, it is important to know all the possible inversions of four-part chords for a number of reasons. Chord inversions add variety to the timbre of your playing, give you convenient options that help minimize left hand movement, and are useful when it comes to connecting chords seamlessly. Without them, your chordal playing is bound to sound 'choppy' and unsophisticated. If, on the other hand, your intended sound is 'unsophisticated'… stick to "power chords" and tablature!
Drop2 guitar chords chart: string groups
The exact fingering for each 7th chord / inversion changes according to the string-group you're on. Bummer, I know. You'll just have to go through all these variations because someone very smart decided, centuries ago, to make the fretboard asymmetrical. Each column in the guitar chords chart above shows a specific string-group, with its specific fingering pattern for the specified chord type / inversion.
Whinging aside, make sure to internalize the process of semitone compensation to the point where you no longer have to think about it and are able to automatically adjust your fingering for any given chord or scale to the string group at hand.