Restraint of body movement potentially reduces peak SPL in western contemporary popular singing

Abstract

In western contemporary popular (WCP) singing, body movement is integral to overall stage performance. However, singers are often directed to stand still while singing during recording sessions or music theatre productions. No assessment has been undertaken by sound engineers or directors to determine whether singers can produce the same sound levels under conditions of voluntary movement restraint. The aim of this investigation was to assess the impact of body movement restraint on sound pressure levels (SPL) in WCP singing. Six professional WCP singers sang a section of a song in two performance modes: first with the directive to perform as they normally would on a stage and then when directed to stand still during their performance. The recordings were analysed for SPL and the results of the two conditions were compared. There was a significant reduction in the SPL recorded by the singers both statistically and acoustically in the ‘non-movement’ condition. This result suggests that restraint of movement during WCP singing is associated with reduced peaks in SPL. Possible reasons for this reduction include the inhibition of respiratory mechanisms for subglottal pressure production and interference with sensorimotor feedback mechanisms such as the autophonic response.