How to Play the Piano in Different Keys

A pianist often finds the need to transcribe a song from one key signature into another. This can facilitate playing with other musicians who only know a song in a certain key or for accompanying a singer who sings best at a lower or higher key. In either case, knowing how to change a song's key signature can help a pianist expand both repertoire and playing abilities, especially when working with other musicians or bands.

Instructions

1. Find out the key signature of the song that needs to be transcribed. Oftentimes, this can be determined by noting the last chord of the song and reconciling it with the key signature. For instance, if the last chord of the song is a G major chord, and the key signature of the song has one F sharp, it's likely the song was originally in the key of G major since F sharp is the only sharp in this key.

2. Determine the key signature that the song should become. If the song was in a minor key to begin with, change it to another minor key, not a major key.

3. Figure out the chord progression of the song. The main consideration in properly playing in a different key is knowing how the chord progression goes.

   Many songs have a 1-4-5 chord progression. The "1" chord of the song is always the tonic, which means that if the song is in the key of A minor, the "1" chord is A minor as well, as the A is the tonic (first tone) of the scale.

   The chords in a key are based on the scale of the key. Each scale has 7 tones, and each chord corresponds to the number of the tone it represents.

   For example, if the song is in A minor, the scale starts at A and progresses to B, C, D, E, F and G. Since there are no sharps and flats in the key signature of A minor, there are no sharps or flats in any of its chords. That's not to say there are no accidentals in the song, but these are the exception, not the rule.

   Thus, when playing in a 1-4-5 chord progression in A minor, the "1" chord is an A minor, the "4" chord is D minor and the "5" chord is E minor.

4. Alter the chords of the song to fit the chord progression. Using the A minor example in the previous step, if the song should be changed to the key of C minor, this will entail working with a key signature with three flats - B flat, E flat and A flat. So the chords will now be C minor, F minor and G minor using the 1-4-5 chord pattern.

5. Change the melody line to fit the new key signature. Remember that the melody's tune and counting will stay exactly the same; it will just be played a few steps higher or lower than in the previous key.

   For example, if the first line of the melody starts with A in the A minor song, start on C in the C minor song, and so forth.

References

• Piano by Chords: Common Chords