In this post and the next we will learn how to identify keys
entirely visually, without having to memorize anything. Keys
tell you what chords and scales work together and are quite
useful. You can use them to figure out songs, compose, or
jam. Just knowing what scale you’re playing will give you a
list of chords to use. Playing 2 or 3 chords can tell you what
scale to play when you solo, and changing keys is easy, just
a chord by chord substitution. You’ve probably noticed that
most songs you play contain 3-6 chords total, just arranged
differently for the various parts. This because they are in a
key, which contains a total of 7 chords plus a scale. Over the
past 6 posts you have learned enough chords and scales,
now it’s time to learn how to put them together and use
them! (Again, a more complete explanation of keys, visual
and otherwise, along with practical methods for their use
is available in my book, “Take Control: for guitar”, available
on Amazon.)
My loose definition of a key is a group of chords and a scale
that work together. The 2 main types of keys used in popular
music are major keys and blues keys. Minor keys are just
major keys starting on a different root, the same as scales.
Here is the key of A Major…
SCALE NOTES CHORDS MODES DEGREE #s
A A major A major key I
B B minor ii
C# C# minor iii
D D major IV
E E major V
F# F# minor F#minor key vi
G# G# dim. vii*
-The left column lists the scale notes. Scales are used to
play melody; lead guitar, horn players, vocalists, and key-
boardists all use the same scales. The scale you have
learned is a pentatonic scale, which is a little more basic,
but it contains the same notes (minus the D and G#),
and will work fine. If you’re interested in the full major
scale, here is position 1 filled in(it has the same roots as
the pentatonic; 1st finger-minor/4th finger-major)
-The middle column lists the chords. Chords are used to
play harmony and are used by keyboardists and guitarists.
You have learned to play 2 versions of all possible major
and minor chords and no version of a diminished chord.
Diminished chords sound nasty and are mostly used in
classical and jazz as passing chords (how many have you
played?) Look one up if you want, I can’t show you every
thing in a blog post!
-The 3rd column lists the 2 main modes in the key. This
shows that this is both the key of A major and the key of
F# minor! Just like your scales, the keys themselves are
both major and minor, just played from different roots.
If you play a 1st position A major scale with the 4th finger
on the 5th fret/6th string, you will see the minor root is
F# on the 2nd fret/6th string just like the example above!
The only difference between the key of A major and the
key of F# minor is what chord and note you consider to
be the root. In the key of A major the 1st chord ,A is the
main chord and in F# minor the 6th chord F# minor is
considered the main chord. As long as your jam focuses
on the main chord you can use any other chords in the
key and you will be in that mode/key. (Some chords will
work better than others, experiment!)
-The 4th column lists the degree numbers. Pros refer to
the chords in a key by Roman numbers, the 1st chord is
a I, the 2nd chord a ii, etc. Upper case numbers mean
major chords (I, IV, V) and lower case means minor
chords (ii, iii, vi), the last chord, a diminished, looks
like a minor with a * after it (vii*). The reason why we
use Roman numbers instead of regular chord names
is to change keys easily! Any I vi IV V chord sequence
is the same sequence for any key. This will make more
sense when we look at the key shape diagram below.
While all the above information is useful to know, you
can see the problem; there are 11 more keys, one for
each note in the chromatic scale, and they all have the
same amount of information and they’re all different!
With each key containing a 7 note scale, 7chords and 2
modes this adds up to 192 bits of information, which
is a lot to remember. Then there’s the obvious question
of how so many self taught musicians manage to write
songs and jam in key without knowing exactly what a
key is. The answer is they play by picture, both the
guitar and piano can be understood visually, this is
why the vast majority of self taught players play guitar
piano or both. We are already playing chords and
scales without knowing all of the theory involved, so
learning the sequence of chords in a key visually is
just the next step. Below is the visual diagram of both
the major and blues keys along with the root notes on
the 6th string. (we are using the 6th string root to
locate the key but you have to use both 6th and 5th
string chords to get all of the chords in the key) The
top diagram on the right shows the location of all the
chords for any major key, the bottom diagram is for
the blues key shape, which we’ll talk about in the
next lesson, ignore that for now. Notice the degree
names instead of fret or chord names. This is what
allows us to play chords in any key.
You can start this shape on any fret and generate all of the
chords for that key. Need the chords for F major key? Move
the pattern to the F root/type I on the 1st fret and you get
all 7 chords in the key of F; just match the degree numbers
with the chord names for that fret. (1st fret-F major, 3rd fret
– G minor, 5th fret A minor, 1st fret, type2-Bb major, 3rd fret
C major, 5th fret-D minor, etc.) Start on any fret, the chords
will be there! The next post will explain the blues key shape,
which is vital for about half of all popular music.
