Using the notes in the D melodic minor scale, make C# the root and think about the scale as an altered Mixolydian. (similar Notice as b13th). The reality that the scale has the augmented fifth or b13th doesn't stop it from being used when You will find there's best fifth https://d-flat-dorian-scale-for-s80245.tkzblog.com/26325201/the-definitive-guide-to-d-flat-dorian-scale-on-saxophone