Can you use both diatonic major and minor scale with any mode?

Question

I am learning the modes right now for the Harmonic Major scale. I usually get the idea of a mode by droning some key and then playing all notes of that modem to sort of internalize its sound, and I thought of also trying diatonic chords instead of just notes. But, the diatonic scale is both major and minor.

Lets take Phrygian b4 as an example, which if I understand correctly is the 3rd mode of Harmonic major scale. My question is this: if I want to learn the diatonic chords for Phrygian b4, should I use the diatonic major, or the diatonic minor, for this mode? Or, to rephrase the question: can you use both diatonics with any mode, or is major only supposed to be used with some modes, and minor with others?

I hope it makes sense. Thanks

Answer 1

'Only supposed to' is the key! So many questions on this site seem to feel that music theory is music law, and to contavene that is bad.

Music theory is basically based on what actually has been found to work well, from centuries ago to now. It's more a sort of guide rather than 'thou shalt'. Often those 'rules' are broken - for many reasons, one being if we all kept religiously to them all, music would have stagnated decades ago.

More important arbiters are ears - if you feel (hear) that something sounds o.k., then it's usable - in fact, oft-times, it could still be justified theoretically!