What Is A Key Signature?
A key signature consists of a series of sharps or flats written immediately to
the right of the clef. A key signature can represent either a major key or a
minor key. The actual key, major or minor, must be determined by studying the
notes and chords used in the music. When a sharp or flat is used in a key
signature, all notes of that name appearing in the music are automatically
sharped or flatted. For example, in E major every F, C, G, and D is sharped.
Major Sharp Keys
The rules for determining major sharp keys are:
- The key of C major has no sharps or flats.
- For key signatures having one to seven sharps, the name of the major key
is one half step higher than the last sharp (the sharp furthest to the right).
Major Flat Keys
The rules for determining major flat keys are:
- The key of C major has no sharps or flats.
- The key of F major has one flat.
- For key signatures having two to seven flats, the name of the major key
is the name of the next to the last flat (the flat 2nd from the right).
Minor Keys
Each key signature can specify either a major key or a minor key. The name of
the minor key is found by first finding the name of the major key and then
counting backwards three scale notes. Sharps and flats present in the key
signature affect the key name.
Relative Major/Minor
Relative keys are major and minor keys that share the same key signature. For
example, E minor is the relative minor of G major and A flat major is the
relative major of F minor.
Parallel Major/Minor
Parallel major and parallel minor are major and minor keys that share the same
name, but use different key signatures. For example, B minor is the parallel
minor of B major, and B major is the parallel major of B minor.
Accidentals
An accidental is a sharp or flat used in the music that is not part of the key
signature. When an accidental is used, it affects all notes of that pitch in
that measure. The accidental is automatically canceled when you move to the
next measure.