nope, Lydian won't be the scale choice over a Cmin7 chord here is why: C Lydian: C D E F# G A B C which will give you a Cmaj7 type of sound (Cmaj7#11, etc) Cmin7 Chord: C Eb G Bb so you have a b3 and a b7, but C Lydian has both the natural 3 and natural 7 If you want to improvise over Cmin7, these are some easy choices: C Dorian: C D Eb F G A Bb C C Phrygian: C Db Eb F G Ab Bb C C Aeolian: C D Eb F G Ab Bb C Cm Pentatonic: C Eb F G Bb and then you can go on and use Dorian #4, Half-Whole Diminished, etc Same concept on the C7 chord. C Ionian: C D E F G A B C C7: C E G Bb so you can see that you need a Bb in the scale Easy approach C Mixolydian: C D E F G A Bb C C Lydian Dominant: C D E F# G A Bb C hope this is helpful~~