Synaesthesia

I saw an (only half serious) article recently that suggested people with phonetic synaesthesia broadly agreed on colours and phonemes. Can't find the link now. But today I had a conversation with a friend who has strong associations between musical keys and colours. We agreed that C major is yellow, but had no other keys and colours in common.

For me, E is white, A is green, D is red, G is brown, C yellow, F blue, B♭ sort of bronze... I don't have strong associations for other keys. Minor keys are darker or paler, so E minor is silver or pale grey. It's definitely tonal centre rather than number of sharps / flats. I'm not aware of making any other sense associations, just this.

Also, come to think of it, I don't have perfect pitch so I can't tell what key something is in just by listening to it. So these colour associations are purely when I'm playing or learning or writing a tune.