Effects of tempo, swing density, and listener's drumming experience, on swing detection thresholds for drum rhythms.

Swing, a popular technique in music performance, has been said to enhance the "groove" of the rhythm. Swing works by delaying the onsets of even-numbered subdivisions of each beat (e.g., 16th-note swing delays the onsets of the second and fourth 16th-note subdivisions of each quarter-note beat). The "swing magnitude" (loosely speaking, the amount of delay) is often quite small. And there has been little investigation, using musical stimuli, into what swing magnitudes listeners can detect. To that end, this study presented continually-looped electronic drum rhythms, with 16th-note swing in the hi-hat on every other bar, to drummers and non-drummers. Swing magnitude was adjusted using a staircase procedure, to determine the magnitude where the difference between swinging and not-swinging bars was just-noticeable. Different tempi (60 to 140 quarter-notes per minute) and swing densities (how often notes occurred at even-numbered subdivisions) were used. Results showed that all subjects could detect smaller swing magnitudes when swing density was higher, thus confirming a previous speculation that the perceptual salience of swing increases with swing density. The just-noticeable magnitudes of swing for drummers differed from those of non-drummers, in terms of both overall magnitude and sensitivity to tempo, thus prompting questions for further exploration.