The Ruler
Let the key signature remember the alterations
G major needs F# wherever F appears, not only in one octave.
Take the guided lessonReference
Build three keys before memorizing a circle
| Major tonic | Written scale | Signature reminder |
|---|---|---|
| C | C D E F G A B | No sharps or flats |
| G | G A B C D E F# | F# throughout |
| F | F G A Bb C D E | Bb throughout |
The signature is shorthand, not a melody
A key signature places recurring sharps or flats beside the clef. Those alterations apply to the named notes in every octave, unless a local accidental changes them.
It does not tell you the rhythm, which note starts the melody, or exactly where home is. A major key and its relative minor share a signature; you will hear that difference shortly.
Read the reminder beside the staff
Switch between C, G, F, and D. The staff positions show the written accidentals; the list spells which letter names they affect in all octaves.
F#
The signature applies to these letter names in every octave.
Build the written notes
Make F major obey the same recipe
Choose the notes after F. Watch the distance from A to the fourth degree: it needs a half step.
Check yourself
A signature contains F#. Does a low F become sharp too?
What to keep
Takeaways
- A key signature saves repeated accidentals across octaves.
- Its note collection still needs musical context to establish a tonic.