Chords in A major key are:
A Bm C#m D E F#m G#dim
But I have listened to songs which contain all these chords but in lieu of C#m it uses C#
So questions are:
1. Will I say this song is on Key-A or something else?
2. If it qualifies on Key-A then why it has deviation from C#m?
3. Are there any rules which govern deviation of one or more chords from a particualr Key?
4. If such deviations are permitted then whats the use of Key, one can pick any combination that sounds good?
Whenever I go deep in theory, I come with only questions And lack of answers fade my interest in theory