#1
Hi I always forget about this kind of stuff when I don't do it for a while so I have a question. When I'm trying to write a song using a certain key, how do I know when I'm staying in that key? Let's say I wanna play in the key of C, what chords can I use or is it just the chords that have their root note on the C major scale?
#2
Any chords that has notes from the scale (or your key) normaly.
#3
Well if its diatonic to C it would be

Cmaj Dmin Emin Fmaj Gmaj Amin Bdim

Can add further extensions to the as well
#4
c major C D E F G A B

root = C =>C D E F G A B => C E G = root maj3 perf5th = C
root = D =>C D E F G A B => D F A = root min3 perf5th = Dm
root = E => C D E F G A B => E G B = root min3 perf5th = Em
root = F =>C D E F G A B => F A C = root maj3 perf5th = F
root = G => C D E F G A B => G B D = root maj3 perf5th = G
root = A =>C D E F G A B => A C E = root min3 perf5th = Am
root = B => C D E F G A B => B D F = root min3 dim5th = Bdim
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#5
Quote by rockinrider55
Well if its diatonic to C it would be

Cmaj Dmin Emin Fmaj Gmaj Amin Bdim

Can add further extensions to the as well

This, and try to put emphasis on the I, IV and V chords, so in the key of C that would be C, F and G.