My band does an extended outro to Cigarettes & Alcohol from the live at Wembley version. It goes into Whole Lotta Love (except with our version I play the Jimmy Page solo 1st) and then a chord progression which I also solo over for a few bars before the big ending… I’ve been revisiting that and trying to come up with better lines, but can’t work out the key?
Here’s an audio clip, but the chords are A, G, D, F. As far as I can hear they are all major…
A minor pentatonic works well over it… But why, because if it’s in A minor then the A and D chords should be minor but they aren’t - at least to my ears?!
This is a great question. Check out the lesson “Theoretical Convergence” from the Harmony Masterclass and read my analysis of “Hey Joe” by Jimi Hendrix. I think this will help answer your question in this case
In short, I would identify this clip you’ve provided as the key of A. Not A minor, not A major, but just A If you absolutely had to pinpoint a key, perhaps you could say it’s in the key of D (the F chord would be the outlier), but this really isn’t a useful or accurate representation of the clip, hence it’s best to think of it as the key of A.