A selection of Scottish Voices videos, taken at various venues in the UK, Europe and the United States:

The video which follows is of a performance of Graham Hair’s O Venezia, Part 2, which consists (currently: 2019) of 3 songs, to texts by Shakespeare (in English), George Sand (in French) and Luigi Nono (in Italian). The performers are  Alison McNeill and Myrna Tennant (sopranos), Laura Smith and Anne Lewis (mezzo-sopranos) and Jacqueline Pollauf (harp).

The video which follows is of a performance by Scottish Voices on April 10, 2019 in the concert hall of the Covington Arts Center of Radford University in Virginia in the United States, of John Gormley’s Spiritus Domini, to a text from the manuscript BN Paris 903 (dating from c.1026). It draws on material from both the Jewish celebration of Shavuot (50 days after Passover) and the Christian liturgy for Pentecost (50 days after Easter). The performers are  Alison McNeill and Myrna Tennant (sopranos), Laura Smith and Anne Lewis (mezzo-sopranos) and Jacqueline Pollauf (harp).

There follows a video of calligrapher Jawdat Khadim Kaiby commenting on his work for the cover of a forthcoming Scottish Voices CD of sacred music.

The performances which follow are by Razia Sultanova (from the Department of Central Asian Studies, University of Cambridge) performing vocal and instrumental music from the Islamic tradition for the aforementioned CD of sacred music. They were recorded in the Burrell Museum in Glasgow in 2016.

 Using Praat to Track the Performance of Microtonal Singing

Below can be found two videos of graphs showing details of the pitch trajectories of performances by soprano Julia Daramy-Williams and mezzo soprano Lynn Bellamy of the song Azrail from Graham Hair’s song-cycle Sufi Fragments (for soprano, mezzo-soprano and digital harmonium). An audiofile of the performance is uploaded to our media/audio page, and the score is uploaded to our media/scores page.

The song is composed using the 19-EDO scale (with 19 equal divisions of the octave).  The digital harmonium part conforms rigidly to this scale. The singers’ intonation, however, is (of course) “free” … in the sense that they are adapting their intonation to the harmonies of the digital harmonium part as the performance proceeds, note by note.

The graph also  shows a best approximation to the rhythmic placement of the onset of each note by each singer, in relation to the precise rhythmic placement of each note as determined by the score, and as performed (precisely) by the digital harmonium part.

Each graph was created by the Director of the Science and Music Group, Dr Nick Bailey, using the we-established software program Praat (see www.praat.org). The animations show details of the pitch detected using a correlation algorithm. On the vertical axis, the centre of each note of the scale is shown, and the line tracks the detected pitch as the singer performs.

The vertical red line is “now” and the  vertical yellow symbols represent the onset time notated in the score, linked with a vertical line to the actual onset time. The onset times in these performances were determined manually, again using Praat, by marking up the segments with a waveform editor.

It is established that professional music practitioners identify a range of (up to about) 30 Hz (depending of context) as “in tune”, and the width of the green bars show that range.

The Praat data has not been sanitised in any way, so one may still identify where there has been an octave error. This is inevitable when using correlation techniques, as the voice signal is obviously very nearly as correlated at two pitch levels as at one. The Praat vocal analysis program is widely respected and recognised as avoiding such errors as largely as possible, as indeed these results show.

Automatic detection of onsets is another story! But we’re working on it!