Circulating Temperaments

A circulating temperament is a periodic scale with the property that for at least one interval class, all of the intervals in the class can be regarded as approximations of a single just interval, but which is not an equal temperament. In the best known examples, the interval approximated is a fifth and the scale has twelve notes to an octave.

A circulating temperament is intermediate between an equal temperament, where all of the intervals in the class are tuned the same, and a MOS scale, where for a class containing a generator all but one of the intervals are tuned the same.

One of the advantages of these tunings, is that because they are not quite equal, each chord (or key) has a slightly different character because the interval sizes have changed slightly.

Articles

• An Introduction to Historical Tunings by Kyle Gann Permalink
• Circulating Temperaments by Gene Ward Smith Permalink
• Well v.s. Equal Temperament by Michael Rubinstein Permalink
• Six Degrees Of Tonality: The Well Tempered Piano by Edward Foote Permalink
• Five Well Temperaments Permalink