The phenomenon of pitch drifting while choirs perform a cappella music is familiar to choral performers and directors, although there appears to be a lack of research into the reasons that it occurs. As part of a research project to investigate possible causes of pitch drift, when singing unaccompanied music, a survey of choral practitioners was undertaken. This paper presents the findings of the survey, which established that a majority of choirs suffer problems maintaining pitch and that varying beliefs about the cause are widespread. In general, anecdotal beliefs regarding pitch drift in a cappella choral singing are confirmed, but the causes remain unclear.
Key words choirs, pitch, pitch drift, a cappella, survey, tonal centre, intonation, beliefs