Blending Between Bassoon and Horn Players: An Analysis of Timbral Adjustments During Musical Performance

Achieving a blended timbre between two instruments is a common aim of orchestration. It relates to the auditory fusion of simultaneous sounds and can be linked to several acoustic factors (e.g., temporal synchrony, harmonicity, spectral relationships). Previous research has left unanswered if and how musicians control these factors during performance to achieve blend. For instance, timbral adjustments could be oriented towards the leading performer. In order to study such adjustments, pairs of one bassoon and one horn player participated in a performance experiment, which involved several musical and acoustical factors. Performances were evaluated through acoustic measures and behavioral ratings, investigating differences across performer roles as leaders or followers, unison or non-unison intervals, and earlier or later segments of performances. In addition, the acoustical influence of performance room and communication impairment were also investigated. Role assignments affected spectral adjustments in that musicians acting as followers adjusted toward a “darker” timbre (i.e., realized by reducing the frequencies of the main formant or spectral centroid). Notably, these adjustments occurred together with slight reductions in sound level, although this was more apparent for horn than bassoon players. Furthermore, coordination seemed more critical in unison performances and also improved over the course of a performance. These findings compare to similar dependencies found concerning how performers coordinate their timing and suggest that performer roles also determine the nature of adjustments necessary to achieve the common aim of a blended timbre.