In
order to create motion and stronger resolution patterns in a comp,
chords from outside the basic progression of a tune are used to form
connections between the written chords. These passing chords are,
by definition, not held or extended, as in using alternate chord changesthey
are used in “passing.” When listening to an experienced comper, you
will hear passing chords being used frequently.
In
the above example, Gb7 (the tritone substitution for C7) is a passing
chord between C-7 and F7. The momentary tension created by the passing
chord against the underlying chord, and the movement of each note
by a half step, results in a strong resolution to F7.
This
use of substitute Dominants is one of the most common passing chord
devices. This can be done more than once in a progression:
Parallel
chromatic chords are often used in passing, in this case, Minor7s:
In the previous example,
the C#-7 passing chord creates movement in what would otherwise
be a static point in the progression. This also works ascending: