Showing posts from March, 2012

Polarized Passing Chords with Extensions

Here’s a little exploration of the diminished seventh  chords and extensions found in the additive major scale (bebop-type scale), also referred to as a polarized passing tone scale.   Passing tone scales are additive scales with a strategically placed chromatic passing tone, placed in such a way as to create a repeating two-chord structure. The scale tone sevenths and extensions found in this scale are essentially two polar/opposing harmonic entities: tonic and dominant. C major bebop (Add b6): The chord extensions found on the tonic side are mostly from the major scale itself or the root lydian scale.   The chord extension examples of the dominant/diminished aspects of this scale are explored using the Symmetrical-Diminished  whole/half (Sym Dim) scale, for example the Ddim7 whole/half scale: D E F G Ab Bb B C (D). C major bebop (Add b6) with extended chords: The above with extended chords. Note the diminished chords are extended with notes from the remai

Diminished Seventh Chord Function

The diminished seventh chord is constructed of four minor third intervals dividing the octave symmetrically. Since there are only twelve chromatic tones, and each inversion will produce four diminished seventh chords, means that in essence there are only three actual diminished sevenths. They are found diatonically in harmonic minor and harmonic major scales on VII (the raised 7th), and, symmetrically in the "whole/half" diminished scale. This discussion is mainly about the symmetrical diminished “whole/half” scale/chord. The symmetrical diminished scale is also "invertable" by minor thirds. For example, C symmetrical diminished (referred to as "Sym Dim" ) scale “inverts” symmetrically to Eb Sym Dim, F# Sym Dim, and A Sym Dim. The remaining notes in this scale i.e. the 9, 11, b13, and Ma7 themselves form a diminished seventh chord (D dim) and inversions that are a whole tone away from the original. The second of the only two true modes of this symm