That's just a cycle of dominants leading back to Fm7.
The Ab7 is like a tritone sub for D7. If you look at what follows
(removing the ii chords for a minute) you would have
D7 -> G7 -> C7 -> Fm6.
or Ab7 -> G7 -> C7 -> Fm6 and then just put ii chords back in.
Depending on the context ii7 and iim7b5 are interchangeable.
>For the A section I see ii/V7/I in F minor followed by ii/V7/I in C major
>with a slight twist in that the ii is ii7b5. The first 4 bars of the bridge
>are ii/V7/I in Bb.
>But I'm not sure how to analyse the 4 bars in question.
>
Normally the Fm7 chords would be Fm6, i.e. a true minor.
Gm7b5 C7 | Fm6 .
What is interesting here is that we have essentially a minor plagal
cadence again, augmented by ii7 chords. Fm being the iv chord of
C.
An interesting twist commonly found in such tunes makes use of the
fact that Dm7b5 is just an inversion of Fm6.
Thus we can move easily between then.
In a minor key, say Fm, a common turnaround would be
Fm6 Dm7b5 | Gm7b5 C7 |
however in this case we resolve the Dm7b5 as a ii chord in C as opposed
to a vi chord in Fm.
>
Reed Kotler
reed@justjazz.com
http://www.justjazz.com