Synchronization in Singing Duo Performances: The Roles of Visual Contact and Leadership Instruction

Abstract

Interpersonal synchronization between musicians during ensemble performances is characterized by continuous micro-timing adjustments due to intentional and unintentional factors supporting expressive interpretations, or caused by noise during the cognitive-motor process. Whether visual contact between musicians and the instruction to act as leader or follower affect synchronization in ensembles remains mostly unclear. This study investigates the role of visual cues and leader-follower relationships in singing performances. Twelve vocal duos took part in the study, singing a two-part piece, which was composed for the study and was mostly homophonic in structure. Four conditions were applied in a randomized order: with and without visual contact, and with a designated leader or follower. The piece was repeated four times in each condition, and the condition presented three times, for a total of 12 performances of the piece in each condition. Data were acquired using electrolaryngograph electrodes and head mounted microphones to track the fundamental frequency estimates of the individual singers. Results show that the presence and absence of visual contact had a significant effect on the precision and consistency of synchronization during singing duo performances. Precision and consistency were better in the presence of visual contact between singers than without, and these effects were associated with the beginning of phonation of the first note of the piece. The presence/absence of visual contact also had an effect on the tendency to lead or lag a co-performer associated with the onset of the first note; the extent of leading was greater when visual contact was absent. The instruction to act as leader or follower did not affect precision or consistency of synchronization, nor did it relate to the observed tendency to precede or lag a co-performer. The results contribute to the tailoring of rehearsal strategies, as singers and directors can be better informed of the factors influencing synchronization and focus on specific areas of difficulty in certain performance conditions, such as first note onsets when performers are not able to see each other.

Perception of synchronization in singing ensembles

“…Recently, a few studies have investigated the role of visual contact and rehearsal on interpersonal synchronization between singers during singing ensemble performances. Research demonstrated that synchronization was better with visual contact between singers than without during singing duo performances [14], and improved between the first two rehearsals in a singing quintet rehearsing a homophonic piece across five rehearsal sessions during a four-month period [15]. However, whether listeners with different levels of expertise can perceive the effects of visual contact between singers and varying levels of rehearsal on the interpersonal synchronization between singers during ensemble performance has not yet been investigated.…”

A Longitudinal Study of Intonation in an a cappella Singing Quintet

“…6 Using the choral synthesis system described in Howard et al, 7 the tuning of student singers was analyzed as they replaced either the alto or soprano line of ''Exercise 3'' when listening to the other three parts tuned either in equal temperament or just intonation over headphones. 8 Singers produced less stable pitches across tones and were more ''out of tune'' when tuning with the justly tuned rather than the equally tempered version of the synthesis, implying that the singers in this study tended towards equal temperament.…”

“…Lx is a non-invasive, widely used method for the analysis of the singing voice. 27 It has been recently used to investigate several aspects of singing ensemble performances, such as synchronization, 26,28,29 blending, 30 and tuning, 5,6 as it allows the identification of the individual contribution of each singer. Each Lx was attached to a preamplifier (ART CleanBox Pro) to reduce noise and interference over long cable runs.…”

“…Singers performed the pieces to the vowel /i/ for consistency with previous investigations analyzing repeated performances in singing ensembles. 26,28,29 It is common to observe slight sharpening in ascending passages when the…”

“…Devaney and Ellis 8 highlighted the importance of considering both vertical and horizontal tuning, proposing an approach to account for both, which utilizes automated f o extraction and machine learning combining theories of sensory consonance and tonal attraction respectively.…”