Key
Signatures
David Loberg Code, Western Michigan University
Keys
come from scales. People sometimes
make the mistake of thinking that keys come from key signatures. They might say that A major has 3
sharps because of the key
signature. This is backwards. It is like saying that deer like to
cross the road at particular spot because there is a Deer X-ing sign there. Key signatures are signs. They help remind us of the key and save us the trouble of
writing the same sharps or flats over and over again. The easiest and best way to determine a key signature is
to think of the scale. When you play a D major scale, you use
an F# and a C#, therefore the key signature for D major has 2 sharps (F# and
C#). For uniformity, the sharps or
flats in a key signature are always written in the same order (regardless of
what order they appear in the scale.)
For
example, an A major scale is: A B C# D E F# G# A. In the key signature, however, the order of the sharps is
rearranged: F#, C#, G#.
The order of sharps is always as follows:
F# C# G#
D# A# E#
B#
Fat Cats Go Down Alleys Eating
Birds
Father Charles Goes Down And Ends Battle
The order of flats is coincidentally the same sequence but backwards:
Bb Eb Ab Db Gb Cb Fb
Big Elephants Always Do Great Circus Feats
Battle Ends And Down Goes Charles' Father
(or) BEAD----------------------------------------------------> Glass Crystal Falls
There are other tricks you
can use to determine the name of the key from looking at the key
signature. For Major keys, the
last sharp in the key signature is always Ti (the seventh scale degree). To find the key, simply go up a minor
second (to Do). For example:
The
key signature has 5 sharps
(F#-C#-G#-D#-A#).
The
last sharp will be A# (Alleys)
A
minor 2nd (half step) above A# is B.
The
major key is B major.
For Major key signatures
with flats, the second to last flat is always Do.
The
key signature has 4 flats
(Bb-Eb-Ab-Db).
The
second to last flat is Ab.
The
major key is Ab major.
Obviously, these tricks
will not work for C major (no sharps or flats), or F major (1 flat). You will just need to memorize
these. Also, these tricks do not work for minor keys.