The Clayson & Garrett Tuning Compass was invented in 1980 by harpsichord builders Richard Clayson and Andrew Garrett. It is a plastic wheel that acts as a dial-up directory of the details of thirteen of the most common temperaments and shows the sizes of the their intervals of fifths and major thirds, expressed in fractions of a comma.

This is a clever little device and handy to have by one’s side at the harpsichord as an aide-memoire when tuning an unfamiliar temperament. It comes in a plastic wallet measuring roughly 16cm square and is accompanied by a small booklet explaining how to use it and giving some brief theoretical background.

The temperaments featured are:

     Arnout van Zwolle (1466)
     d’Alembert (1752)/Rousseau (1767)
     Bendeler III
     Equal
     Kirnberger III
     Meantone (quarter-comma)
     Neidhardt (1724)
     Neidhardt (1732)
     Silbermann (sixth-comma meantone)
     Tempérament ordinaire
     Vallotti
     Werckmeister I (‘III’)
     Young II

This can only be obtained direct from Andrew Garrett or myself. I am happy to send it anywhere in the world. The cost is presently 15 GBP or 18 euros including postage. Please send me a message via my contact page.