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Pitch Drift in a cappella choral singing

Pitch Drift in a cappella choral singing

Welcome to this website which covers all aspects of our research project at The Open University investigating choral singing.

The research subject introduced here considers why choirs are not able always to maintain the pitch of the piece of music when they are performing a cappella. That is to say, when the performance requires no instrumental accompaniment or when the accompaniment is removed for musical effect and then, at some time later, reintroduced.

In the case of the former, the drift from the intended pitch may not be so obvious to an audience other than to those with knowledge of, and the ability to recognize, the pitch. In the case of the latter, however, the reintroduction of instrumental accompaniment will make any drift in pitch very obvious.

A survey of over 200 choral practitioners closed in May 2014 and since then an initial analysis of the responses has been undertaken. The results were presented at the 40th Anniversary Conference of the Institute of Acoustics held between 15th and 16th of October 2014 in Birmingham. The paper is available via a link on the "Papers" page of this website.

Experiments with choirs are now in hand with choirs around the country. The "News" item on this page details which choirs are currently involved. The research team is very grateful to these choirs for giving up their time and efforts for pitch rift research. The experiments are three-fold involving: (a) measurements of the rehearsal venue acoustic properties; (b) a survey of the pitch discrimination abilities of the singers; (c) analysis of recordings of two short unaccompanied songs over a twenty week period. The total involvement for each choir is no more than five minutes of rehearsal time plus brief feedback from the choral director. All data collected is entirely anonymous for use only with this research. If your choir is keen to take part please contact the research team via the research mailbox:

Thank you for taking time to view this site.


  • Two more choirs join the research programme

    [February 2016] Two mores choirs are taking part in rehearsal experiments …more
  • Another choir joins the research programme

    [January 2016] Another choir is taking part in rehearsal experiments …more
  • Two more choirs have joined the research programme

    [December 2015] Two more choirs have agreed to take part in rehearsal experiments …more
  • Choral experiments to start in September

    [August 2015] To date six choirs have agreed to take part in rehearsal experiments …more
  • Experiments with choirs to start shortly

    [June 2015] Choirs are being sought to undertake rehearsal experiments …more
  • ABCD to publicise research

    [January 2015] The Association of British Choral Directors is to publicise Pitch Drift research …more
  • Institute of Acoustics presentation

    [October 2014] Institute of Acoustics' 40th Anniversary Conference …more
  • Presentation at forthcoming conference

    [July 2014] Institute of Acoustics' 40th Anniversary Conference …more
  • The survey is now closed

    [May 2014] Please email us for further information. …more
  • Still time to complete the survey

    [April 2014] The survey closes at the end of April, so there may still be time to complete it. …more
  • Research is publicised in OU Life

    [March 2014] The research was publicised on the OU intranet on 21st March. …more
  • Now up to 164 responses to the Survey!

    [February 2014] A big thank you to all who have taken the time to complete my Survey - but still more responses will be very useful. …more
  • FutureLearn is a great idea and it's free!

    [January 2014] FutureLearn offers free online courses (MOOCs) provided by a consortium of Universities from around the world …more
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