How to Tell the Key of a Song
One key or another is always assigned to each and every music piece. It may be in the key of Bb or maybe even the key of E. The beginning of the score is used to determine the key signature that will be used throughout the piece, like if there are flats or sharps that will be used and which scale it is to be played or sung in.
A key signature is included in each and every musical piece. This information is written right after the clef (shown on the staff) and is explained with symbols stating the number of flats (b) and the number of sharps (#). As you look over the beginning of the lines of music you will recognize a grouping of flats and sharps, which are not ever used simultaneously. They will appear separately on a space or on a line of the music staff and will be placed with the specific notes that will be affected by them. For example, if the music is to played using an F#, the sharp symbol, the #, will be placed on the top line of the staff. This will tell the person that is reading the music that each time an F is played, no matter if it is on top of the staff, in the first space, or below or able the staff (indicated by the ledger lines), this note should be placed as F#.
If a note that is dictated as sharp or flat by the key signature is to be played as natural, an accidental is placed before the note. For example, if an F (natural) is to be played in the key of G, an accidental has to be placed before it so it is not played as an F#.
The key signature is used so that the number of sharps or flats that are used in within the music itself will be limited. With this said, the musician can tell from the start that each time the note F is played it is to be played as a #. There is no need to put the # in front of each and every F note in the sheet of music. If the signatures were not used, the music would be very hard to decipher because there would be flats and sharps scattered throughout the music, causing cluttering on the lines of music.
The most common key signatures are listed below along with the notes that are affected by them:
Key of C: No flats or sharps
Key of G: One designated sharp (F#)
Key of D: Two designated sharps (C# and F#)
Key of A: Three designated sharps (C#, G# and F#)
Key of E: Four designated sharps (D#, F#, C# and G#)
Key of F: One designated flat (Bb)
Key of Bb: Two designated flats (Eb and Bb)
Key of Eb: Three designated flats (Ab, Bb, and Eb)
There is also a relative minor for each key. The similarities of the relative minor and the major are nearly all the same (though started in a different place, the scales are the same) they are not thought of as the same. The note that is found a minor third down from the major (key) is considered to be the relative minor. It is also known as the sixth note in the major scale. The A note is the six note of the C major scale, for example. This means that the relative minor to the C scale is an A minor. It is extremely common for music to use a particular key’s relative minor so if you know about them it makes understanding the chord progression in a song much easier to comprehend.
Below are some of the keys and their relative minors (keys):
The relative minor for C is A minor
The relative minor for D is B minor
The relative minor for A is F# minor
The relative minor for Bb is G minor
When a musician that is experienced plays in a setting that is not formal (without written music) all they need to know is what the key is to the song that they will be playing and they will immediately know the sales, or melodies, as well as the chords that are necessary to play it well.
Finally, it is not unusual for a song to be written in more than one key - to change somewhere in the middle of a song. Such key changes can be a challenge for relatively new musicians.
