"Unprofitable Instruments" Monochord demonstration, 2021

Kate McWilliams of "Unprofitable Instruments" demonstrates how to use a monochord to explore musical ratios.


A monochord is a one-stringed instrument that was used throughout the middle ages as a tool to explore the relationship between mathematics and sound. For instance, if a string is divided in half, it produces a tone one octave higher than the open string. Other ratios such as 3:2 (fifth), 4:3 (fourth), and 9:8 (whole tone) can be found on the monochord, at once clearly visible and audible. A section on how to ‘divide’ the monochord was a standard inclusion in medieval theoretical writings on music. In many instances, theorists described tuning systems to meet the priorities of the music of their time.

The monochord was also used as a practical tool for learning new music by plucking out the notes (as we might do today on a piano).

Instructions for dividing a monochord typically start by dividing the string into ninths or fourths, then marking certain of those points with note names. Then the distance between one of the new notes and the end of the string is divided and marked, producing more notes. The divisions are made by finding harmonics or by using a divider (a long-armed compass without the pencil). When the scale is laid out on the monochord, you set the moveable bridge to the note that you would like, and pluck the string.


For more information on monochords, as well as how to order one, see
http://www.unprofitableinstruments.co...

See "The Monochord in the Medieval and Modern Classrooms" by Kate Buehler-McWilliams and Russell E. Murray, Journal of Music History Pedagogy, Vol 3, No 2.
http://www.ams-net.org/ojs/index.php/...