Here we are talking about scales again but wait, this is a little different. Often, we see lessons saying ‘use altered scale over this chord’, ‘diminished scale over that chord’ etc. which is perfectly fine! Nothing wrong! However, I like shortcuts, I like to THINK simpler.
If I were to go through chord changes like a 2-5-1-6 in C (Dm7 – G7 – CM7 – A7) and I think, ‘Okay lets do a D Dorian for the Dm7, G half-whole diminished over G7, C Ionian over CM7 and A altered over A7.’ That’s quite a lot of stuff going on and by thinking of what scales to use over each chord, my phrasing suffers. To me, that thinking is all temporary that lasts 1 bar, or some times even just 1 beat! Good phrasing is all about connecting the dots (notes in this case) from one to the other. Think of the big picture instead of focusing on those little tiny things that we lose the whole situation!
Altering the key scale.
2-5-1-6 in C, keyword is C so I just think of the key center, which is C major. Over the Dm7 chord, I’m aware of the chord tones and this is easy because C major scale over a Dm7 gives a D Dorian anyway. Now G7, lets do some diminished sounds but I don’t THINK of a diminished scale. Instead, I’m aware of the chord at the moment and I know it belongs to C major. To get the diminished sound, I hit the G# with passion since it is the b9 of G7. I’m still thinking of the key center (C major) because that’s the big picture. On to CM7, C major home base. I might hit the F# to get some Lydian sounds. Last is A7, lets try some altered sound shall we? I’m still thinking of C major mind you but now, since it’s an A7 chord, I would add a C# into my phrasing to spell out the chord (C# is the 3rd of A7) as well as adding a Bb (b9) and Eb (b5) to spice things up. For the rest of the ‘altered’ notes which are C and F, well these notes are in C major already. I don’t think of the altered scale. Instead I add in the altered notes into my mindset of C major to get the altered sound. I might just hit an A altered scale as well WHILE thinking of C major (multitasking!).
Works for me. What about you?
To sum it up, the key center is the big picture and all the subsequent scales over different chords are the small details. Connect the small details to fit in the big picture. It is not wrong to think in terms of different scales over chords but do they connect? If they do, excellent! As for me, I prefer thinking of the key center and add or change notes as I approach different chords. It’s just easier for me. There’s no right way to do it as long as it sounds right so if you’re feeling good with your current method which is different, then it’s good! Don’t follow blindly what’s written on the internet (including my posts) just because it’s on the internet and, happy practicing!