Watch the Diminishing Returns online guitar lesson by Fareed Haque from 30 Beginner Jazz Licks You MUST Know
This is a classic bebop lick, outlining the ii minor chord, in this case Dm, going on to G7 with b9 and #9 (Ab and A#) and finally ending on B natural, the 7th of C major 7. This lick happens to also outline a diminished scale. Diminished sounds are signature jazz sounds and are used by jazz players from Django Reinhardt, to Dizzy Gillespie, Charlie Parker, (pianist) Bill Evans, Miles Davis, and many others. Get to know them!
So, what is a diminished scale anyway? Simply put, a diminished scale is built by adding a leading tone to each note in a diminished chord arpeggio. A leading tone is a note a 1/2 step below each root. Since a diminished chord is composed of all m3 intervals, each note can be the root. So, we can add 4 leading tones, thus creating an 8-note scale. Since most of our scales are 7 notes scales, we call this 8-note scale an octatonic scale.
To finger this easily, start with your first finger on the first note B, then slide up to the C, then use 3, 4 for the next notes. Use the same fingering: 1-1-3-4 for the notes on the D and G string.
Historical side note: This scale was discovered by ancient mariners who heard the distant haunting mating calls of the Giant Pacific Octopus, not the more commonly known Enteroctopus dofleini, but actually the less well known (and infinitely more swinging) Enteroctopus doubeidoubei. Not surprisingly these marine musicians use 8 note scales, though they have been known to use 16 note scales, when the mood strikes.