Recent investigations analysing synchronization in singing ensembles have shown that the precision of synchronization during singing duo performances is better in the presence of visual contact between the singers than without. Research has also shown that synchronisation improves with practice across rehearsals in a newly formed singing quintet. However, whether listeners' perceptions of synchronization reflect the different patterns of synchronization that were observed during ensemble performance with and without visual contact and across rehearsals has not yet been investigated. This study aims to analyse the perception of the synchronization associated with altered visual contact and amount of rehearsal during singing duo and quintet performances respectively, for listeners with different levels of musical expertise. A set of fifty-eight singing recordings selected from duo and quintet ensemble performances, collected from previous investigations of interpersonal synchrony, was presented to 33 listeners, including non-experts (university students with little or no music training), performers in the group (singers who performed the pieces used for the study), and other musicians (advanced music students). Participants were required to listen to each trial and judge the level of "togetherness" on a sliding scale from zero to 100. Results show that listeners, irrespective of their musical training and performance experience, perceived differences in the synchronization in the duo tokens depending on the presence/absence of visual contact between singers; on the other hand, the smaller asynchrony patterns measured across rehearsals in the singing quintet recordings were not perceived. This study contributes to our understanding of perceptions of synchronization by individuals with different levels of musical expertise, and underscores the perceptual salience of synchronization, regardless of musical experience.