When to use different scales or modes over chord progressions?
I know my major/pentatonic/blues scales pretty well, and I can apply it pretty fluently when playing over 1-4-5-min6 chord progressions, but I find that when I try to improvise over more "non-standard" progressions (for example, a 1-flat7-4 progression like EMaj-DMaj-AMaj), I'm pretty much lost. I know about the different modes of the major scale and how to find them, but I'm not sure how to choose a certain mode to go well with a certain chord progression. What's a good way to quickly identify the mode(s) I should think about when given a chord progression? If you can talk about the E-D-A example above, that'd be great.