I wish to sell nothing, but maybe what I said was unclear or misunderstood.
The Eb minor IS the ii chord of Db. However, anytime you tonicize a chord
with its dominant, you are playing in that new key. I am not suggesting
that the tune is in Eb minor, but to negotiate the Bb7 to Eb minor you have
to play in the key of ii: 6 flats. Listen to how Coleman Hawkins sets up
the ii chord: almost every time he uses the D natural and C flat from Eb
minor.
It's the same in tunes with a progression like F - F#o7 - Gm7 - C7. No one
would argue that this in the key of F, but to negotiate the F#o7 chord, the
viio7 of Gm you are no longer in the key of F, but the key of ii, G minor.
G minor necessitate the use of F#, as the leading tone, and Eb, the second
flat of the G minor key signature. So when you are playing a simple tune
like Stompin' at the Savoy in Db, in order to get to the ii chord in m.5,
it is often preceded by a Bb7(b9), that b9 being the Cb or sixth flat.
Check out Clifford Brown's solo for the Cb in mm.5, 12 and 28 of the form.
Since tunes rarely stay within the strict confines of diatonic chords
without temporarily modulating, or at least tonicizing some other key
areas. Those are keys that are typically on accidental away from the tonic
key. So that in order to play in the key of C major (no sharps, no flats)
you may have to deal with other keys:
A minor (usually needing a G# and an E7 chord to get there)
F major (needs a Bb and a C7 chord)
D minor (needs the Bb as does F major, but also needs the C#)
G (needs F# and a D7)
E minor (needs F# and D# with a B7)
Most of what I stated here is basic theory and was included not to insult
any one's intelligence, but more for being thorough or clarity for those on
the list who may not have a grasp on theory quite yet. I felt it best to be
thorough, since my previous note created ambiguity. I hope that clears up
any misunderstanding.
_______________________________________
Bert Ligon
Director of Jazz Studies
_______________________________________
School of Music
University of South Carolina
Columbia, SC 29208
Voice: (803) 777-6565
Fax: (803) 777-6508
bligon@mozart.sc.edu
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