chord theory part 1
we looked at major, minor and suspended triads (three note chords). In
2 we learned how to construct augmented and diminished
triads. These five chord types form the basis of all chords.
Today we're looking at a family of chords
that contain four notes, known as 7th chords.
These can be seen as primary extensions of the basic, three note
triads we learned in the first two parts.
In music theory, the 7th
chords are (with their tones/intervals):
1, 3, 5, 7
1, 3, 5, ♭7
1, ♭3, 5, ♭7
Minor major 7th
1, ♭3, 5, 7
1, 3, ♯5, ♭7
1, ♭3, ♭5, ♭7
1, ♭3, ♭5, ♭♭7
1, 2/4, 5, ♭7
Don't get confused at this
stage with their names. Just focus on getting to know how each one is
built and the unique sound each one creates. A lot of this knowledge
naturally if you know
Here's a useful introductory video on 7th chords and what the "7th"
Major 7th chords have been described as "dreamy" and relaxed or
lacking tension) and are
therefore often used for resolution
in chord progressions.
Remember that a major
triad was the Root, 3rd and 5th notes from the major
scale? Well a major 7th chord is the triad with an added
The Root (1),
(3), 5th (5)and 7th (7) form
7th chord. For example...
Notice how it just uses those
4 tones (1 3 5 7), unmoved from the major scale.
Here's a common major 7th
chord shape rooted on the A string...
don't have to include that higher 5th voicing on the high E string, but
the option is there.
The major 7th chord is abbreviated as "maj7", so if the root note
lied on A,
it would be Amaj7.
Sometimes, it may be abbreviated further to "M7" (capital M), e.g. AM7,
BM7, CM7 etc.
Dominant 7th chords include a flat/minor 7th
of a major 7th
(7). A way
of visualising this is if you flatten the 7th from the major 7th
(its natural major scale position) one semitone (the equivalent of one
Note, in that second example, there is no 5th. This is fine, as the 5th
is considered a "neutral" tone and is often left out to accomodate a
certain fingering/position. The key tones are the root, 3rd and b7. It
still has that dominant 7th sound without the 5th and that's what
Dominant 7th chords are abbreviated by simply adding a 7
to the root letter.
For example, C7, B7, D7 etc.
When you see just the 7 added like this, we can assume that the 3rd and
5th (with some exceptions) of the major triad are also part of the
Sometimes they may be written as Cdom7, Bdom7, Ddom7 etc.
Minor 7th chords are a minor
triad (1 ♭3 5)
with a flat/minor
Two commonly used minor 7th chord forms, rooted on the E and A
Remember that you can cut
5/6 string chord forms down.
long as the main elements of the chord are included, you'll get the
sound you need. In fact, a lot of the time you won't even need to
the root, as the bassist will often cover that.
We abbreviate minor 7th chords as "m7". E.g. Cm7, Bm7, Dm7 etc.
sometimes as "min7".
major 7th chords
"Minor major 7th" might sound contradictory, but as the minor comes
first these can be seen as minor chords/triads with an added major
This wonderfully mysterious sounding chord is often
used as a more tense minor tonic/resolution chord within harmonic or
melodic minor based progressions. Also used in between regular minor
and minor 7th chords, creating a harmony line through both 7th
We can abbreviate this as "mM7" or "minMaj7". E.g. CmM7, BmMaj7 etc.
Remember, with a good knowledge of the fretboard, you'll start to see
these chord forms pop up all over the neck. This
software will help you see the big picture.
I think you can see where we're going with this now!
2, we looked at augmented triads (1 3 ♯5), well an augmented
7th chord is exactly that with an added flat/minor
Very tense sounding chords, used a lot in jazz in the dominant (V)
position, before returning to the tonic.
The abbreviation for augmented
7th chords is "aug7". E.g. Baug7, Caug7,
Eaug7 etc. and occasionally you'll see it symbolised with a + sign,
e.g. B+7, C+7, E+7.
part refers to the sharpened 5th and the 7 refers
to the flat 7th.
Half diminished? Well, you'll know from part
2 how a regular diminished triad is made up (1 ♭3 ♭5). A half
diminished chord is the diminished triad plus a flat 7th tone.
It's a bit of a confusing name, I know! Just make sure you learn the
elements that make up this chord to clarify in your own mind...
When writing the chord, we use "m7♭5" (minor 7th, flat 5th) to avoid
confusion. E.g. Bm7♭5, Cm7♭5 etc.
Sometimes, you'll see a special symbol used for half diminished chords
- ø - e.g. Bø, Cø etc. However, I would discourage people from using it
as not everyone knows what it means and music should be a common
So really, it's just a minor 7th chord with a flat 5th!
7th chords involve
the 7th being flattened twice
from its natural major scale position. Incidentally, this puts it in
the position of a major
6th. However, in the context
of diminished chords
(1 ♭3 ♭5) we
label it as a double
flat 7th (♭♭7),
also known as a diminished
In other words, it's a half diminished chord with the 7th flattened one
more semitone (or fret).
The abbreviation of this chord is simply "dim7", e.g. Cdim7, Fdim7,
Gdim7 etc. but can also be abbreviated using the diminished symbol
(which looks like a degrees symbol) as °7 , e.g. C°7, F°7, G°7 etc.
As I said at the beginning,
don't worry yourself over why
some of these chord names sound a bit confusing, just know what
notes they involve and the sound they create.
Just think of diminished 7th
chords as minor chords with a flat 5 and
double flat 7th.
part 1 we learned about suspended triads, where the 3rd of a major or
minor triad is replaced with the 2nd or 4th (sus2 and sus4
These triads can also be extended by adding the flat 7th (♭7). Starting
with 7th suspended 4th...
Abbreviated as "7sus4", e.g.
C7sus4, E7sus4, G7sus4 etc.
And here's a commonly used A
string chord shape for a 7th
Abbreviated as "7sus2", e.g.
D7sus2, F7sus2, A7sus2 etc.
You should now have a
good idea about how
to construct and identify 7th chords. They add more depth to the
forms, so get to know them well.
In the next guitar chord
theory lesson we'll cover further
chord extensions such as added 6ths and 9ths and creating
"13th chords", stacking our chords even higher.
We only looked at the most
common chord forms in this lesson. To truly dominate the fretboard with
any one of these chord types, I highly recommend you spend some time
studying the fretboard - this interactive fretboard
learning software will make sure you don't bore yourself to
death in the process!
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