Let's say I'm creating a bass line to a song that's in the key of E major. The main chord progression of the song is simple, just E major, Ab major, C# minor and B major. So... E - Ab - C# - B I wanted to use a lesson on creating bass lines with arpeggios for this one. The question I have is that the arpeggio shape for the Ab is a minor (being that it is the 3rd of the major scale) but the chord in the song is an Ab major. So I shouldn't arpeggiate that Ab as a minor, I should arpeggiate it as a major? But that then uses a C, which is not part of the E major scale. Can anybody shed some light on this?