Watch the Modal Study #5 online guitar lesson by Jon Finn from Modal Rock Soloing
C Aeolian is an Eb major scale starting on its 6th degree. C Aeolian is also a C major scale with b3 (Eb), b7 (Bb ) and b6 (Ab). Another way to think of it is that C Aeolian is a C dorian scale with a b6. Further, C dorian is a C minor pentatonic scale (1, b3, 4, 5, b7 or C, Eb, F, G, Bb) with 2 (D) and b6 (Ab) added. In order for this scale to sound truly Aeolian you have to emphasize both the 2 (D) and b6 (Ab) of the scale. The b6 (Ab) distinguishes it from the dorian (which has nat. 6). The 2 (D) distinguishes it from the b2 (Db) in C Phrygian. The b6 implies "Not Dorian" while the b2 says "Not Phrygian."