Part VI: Seventh Chord Extensions
(9ths, 11ths, and 13ths)
So we stacked 3 thirds/intervals and got a 4 tone
chord...letís take a step further: into the second octave.
Now that the chords are starting to get quite large, we
run into a little problem. The number of types of chords for 9ths,
11ths, and 13th chords are smaller that 7ths
because there are a lot more tones involved and the chances of a tone
clashing with another and causing dissonance increases. Dissonance can
be good but a chord made up of 6 minor seconds is considered pleasing by
Letís examine 9th chords first. As usual,
there are your typical types, you would expect. First and foremost, let
us look at the major 9th chord. Much like the major 7th,
you just you all the odd numbers of the major scale up to 9. Maj9 = 1,
3, 5, 7, 9.
[Picture of Maj9]
Also, letís make sure to note its intervals: M3, m3, M3,
Something you should note at this point. You know what
the 1, 3, 5, and 7 tones of a scale are, but what about the 8? Well
thatís just the octave right? Set of eight notes. The 9? Yes, itís just
the 2 of the scale and octave higher. This distinction becomes important
in the next section.
The next 9th chord we will look at is the
minor 9th. Essentially itís a minor 7th chord with
the added 9th of the major scale. Nothing more. Since we know
what the minor 7th looks like this should be easy. min9 = 1,
b3, 5, b7, 9.
[Picture of min9]
Intervals: m3, M3, m3, M3
Now for the Dominant 9th. Well this is a
surprise...itís the dominant seventh with a ninth added. Dom9 = 1, 3, 5,
[Picture of Dom9]
Intervals: M3, m3, m3, M3
Those are the most common ones, but there are some more
irregular ones as well. A lot of them cannot be described without
knowledge of the following section.
Next is the
chord. This is a fairly simple idea as well. Remember 6th
chords? This is no more than a 6th chord with an added 9th
This page will be updates
soon to include more information on further extensions.