Look at the previous song, and notice that although the previous piece is in the key of A minor, all the chords it contains are also in the key of C major. For every key signature there are two possible keys, one major and one minor. These are called relative keys, e.g., the key signature for the key of C major contains no sharps or flats, as does the key of A minor. The key of A minor is therefore called the relative minor of C major.
The key signatures for C Major and A minor are identical - no sharps or flats.
To find the relative minor of any major key, start on the 6th degree of the major scale. The following example shows the scale tone chords for the key of A natural minor. Notice that the chords are exactly the same as those contained in the key of C major. The only difference is the starting and finishing point. Because the minor scale starts on A, A minor will now be chord I instead of VI .
The following progression could be described in two possible ways. It could be called VI V VI IV V in C major or I VII I VI VII in A minor. Because the progression has an obvious minor sounding tonality, musicians would use the second description. Experiment with other chord combinations in the key of A minor.
The next example shows the scale tone chords for the key of E natural minor which is the relative minor of G major, as shown by the key signature. As with the keys of C major and A minor, the chords will be the same as those of its relative, but the starting note is E instead of G, so E minor will be chord I .
Like music written in major keys, anything in a minor key can be transposed to other keys. The following example shows the piano part from example 136 transposed to the key of E minor.
Sometimes only two chords are needed to give the effect of a minor key. Notice also the use of space in this piano part. Particularly when playing with other instruments, it is not necessary to play all the time. Try transposing this part to the key of A minor.