Bar-line shift

File:Bar-line shift on rhythm changes B section.png B section {{audio|Bar-line shift on rhythm changes B section.mid|Play}}.]]

In jazz, a bar-line shift is a technique in which, during improvisation, one plays the chord from the measure before, as an anticipation of a chord, or after the given chord, as a delay, either intentionally or as an "accident."Coker, Jerry (1997). Elements of the Jazz Language for the Developing Improvisor, p.83. {{ISBN|1-57623-875-X}}.

Bar-line shifts may be caused by a novice having lost their place in the chord progression, but is most often attributable to: "(1)...harmonic generalization, as in the case of playing a half-diminished seventh chord to V7 (+5, +9) progression [II-V-I turnaround] as only a V7 (+5, +9); or (2) the player wanted to play the previous chord (though it has already transpired), but was either pausing momentarily (as in taking a breath), and decides to adopt the 'better later than never' attitude." An example of a "very intentional" bar-line shift may be found on Cannonball Adderley's solo on "So What," "in which he deliberately enters and exits the bridge early, causing considerable tension, since the chord of the A section (D-) is one-half step lower than the chord of the bridge (E{{music|b}}-)." Other notable performers to use this technique include Charlie Parker, Coleman Hawkins, and Pat Metheny.{{Cite web |title=Bar-Line Shift and Superimposition |url=https://www.thejazzpianosite.com/jazz-piano-lessons/jazz-improvisation/bar-line-shift-and-superimposition/ |access-date=2024-09-09 |website=TJPS |language=en-US}}Heerspink, Lee A. (2020) A Bright Size Transformation: Examining Pat Metheny’s Improvisatory Evolution through Select Original Compositions from the Album Bright Size Life (1976), pg. 46. ISBN 9798641899565

File:Bar-line shift on metric accent.png vs. second two lines {{audio|Bar-line shift on metric accent.mid|Play}}.]]

Outside of jazz, a bar-line shift may be less than a bar, causing a change in the metric accent of the melody and its cadence.Newman, William S. (1995). Beethoven on Beethoven: Playing His Piano Music His Way, p.170-71. {{ISBN|0-393-30719-0}}.