Modal tunes -- Modal tunes can be a blast to play because anything goes. On the other hand, they require a great deal from the improviser in that they provide practically no input as a composition. Typically in AABA form, usually in D minor, B section being in Eb minor. General rule is use Dorian mode starting on root. In this case the 7th is not raised theoretically; however, most improvisers raise and lower anything and everything at will!! See Miles Davis. Arguably the most well known of modal tunes is - ‘So What’. It is an interesting tune in that the bass traditionally plays the melody.