Is it right for a 2-5-1 in a minor key to sound exactly like a 7-3-6 in a major key??? Or am I just confused...
of course. Thats all a 7-3-6 is, a 2-5 of 6. The 3 in the progression becomes a secondary dominant which turns it into a 5. The minor chord a fourth below that 5 (or 7 in this case) gives it the 2-5 sound.
a 7 in a major key is diminished or a half-diminished seventh chord just like a 2 in a minor key.
Key of Cmajor CEGB DFAC EGBD FACE GBDF
ACEG BDFA
1 2 3 4 5
6 7
Key of Aminor (harmonic)
ACEG BDFA CEGB DFAC EG#BD FACE G#BDF
1 2 3 4 5 6 7
Now if you were playing a 736 in C major, your 3 EGBD, would include the raised G as well. We know the G# doesnt belong so since the alteration creates a dominant chord it is a secondary dominant, or you could look at it as tonicizing the key of Aminor for that progression.
Now look at it this way
Key of Cmajor CEGB DFAC EGBD FACE GBDF ACEG BDFA
1 2 3 4 5 6 7
Key of A natural minor 3 4 5 6 7 1 2
We're looking at the natural minor on this second example because it is the same exact notes derived from the major scale. The exception of G# comes in because when you're using a cadence in the minor key the 7th degree (G) is usually raised, to make the 5 chord a major triad or dominant seventh and provide a leading tone to the tonic. Thats atleast how we do it in our music. So its easier if you're putting together diatonic chords for a minor key to use the harmonic minor as your scale of choice as opposed to the natural minor.
