Passing chord

Passing chord in B♭ from across the circle of fifths (tritone, see also tritone substitution): B♮7 Playⓘ.[1]
The circle of fifths drawn within the chromatic circle as a star dodecagon.[2]

In music, a passing chord is a chord that connects, or passes between, the notes of two diatonic chords.[3] "Any chord that moves between one diatonic chord and another one nearby may be loosely termed a passing chord. A diatonic passing chord may be inserted into a pre-existing progression that moves by a major or minor third in order to create more movement."[4] "'Inbetween chords' that help you get from one chord to another are called passing chords."[5]

For example, in the simple chord progression in the key of C Major, which goes from Imaj7/iii7/ii7/V7:[4] 

|Cmaj7     |Em7      |Dm7    |G7   |

the diatonic (this means "from the scale of the tonic") passing chord (Dm7) may be inserted: 

|Cmaj7 Dm7 |Em7      |Dm7    |G7   |

or the chromatic passing chord (Ebm7) may be inserted: 

|Cmaj7     |Em7 Ebm7 |Dm7    |G7   |

or one or more secondary dominants may be inserted: 

|Cmaj7  B7 |Em7  A7 |Dm7   |G7   |    (in this example, the B7 is the secondary dominant of Em7 and the A7 is the secondary dominant of Dm7)

A chromatic passing chord is, "a chord that is not in the harmonized scale"[6] For example, one or more diminished seventh chords may be inserted: 

|Cmaj7  D# dim7' |Em7  C# dim7 |Dm7   |G7   |    (in this example, the D# dim7 is the viio7  of Em7 and the C# dim7 is the viio7 of Dm7)

Passing chords may be consonant or dissonant[7] and may include flat fifth substitution, scalewise substitution, dominant minor substitution, approach chords, and bass-line-directed substitution.[5] Passing chords may be written into a lead sheet by a composer, songwriter, or arranger.

As well, particularly in smaller ensembles, such as the organ trio or jazz quartet, the comping (chord-playing) rhythm section instrumentalists (e.g., jazz guitar, jazz piano, Hammond organ) may improvise passing chords. With large ensembles, such as a big band, the comping players may have less freedom to improvise passing chords, because the composer/arranger may have already written in passing chords into the written horn parts, which might clash with improvised passing chords played by a comping musician. The freedom of comping musicians to improvise passing chords also depends on the tempo. In a very slow ballad, if a chord-playing musician adds in an improvised diminished chord for a half a bar, this may "clash" with the melody notes or chords played by other performers. On the other hand, in an extremely up-tempo (fast) bebop tune, a comping musician could add improvised passing chords with more freedom, because each bar goes by so fast.

  1. ^ Shanaphy and Knowlton (1990). The Do It Yourself Handbook for Keyboard Playing, p.68. ISBN 0-943748-00-3.
  2. ^ McCartin, Brian J. (1998). "Prelude to Musical Geometry", p. 364. The College Mathematics Journal 29, no. 5 (November): 354–70. (abstract) (JSTOR).
  3. ^ Wyatt and Schroeder (2002). Hal Leonard Pocket Music Theory: A Comprehensive and Convenient Source for All Musicians, p.144. ISBN 0-634-04771-X.
  4. ^ a b Rawlins and Bahha (2005). Jazzology: The Encyclopedia of Jazz Theory for All Musicians, p.104. ISBN 0-634-08678-2.
  5. ^ a b Sokolow, Fred (2002). Jazzing It Up, p.9. ISBN 0-7935-9112-0.
  6. ^ Berle, Arnie (1995). Understanding Chord Progressions for Guitar: Compact Music Guides Series, p.34. ISBN 0-8256-1488-0.
  7. ^ Alfred White, William (1911). Harmony and Ear-Training, p.158. Silver, Burdett & Company.