Definitions of tuning terms

© 1998 by Joseph L. Monzo

All definitions by Joe Monzo unless otherwise cited


unison vector


    A term used by Fokker to describe what I call a xenharmonic bridge: an interval which is small enough that it can be disregarded, thereby enabling a ratio with one set of prime-factors to substitute for a ratio with a different set of factors.

    The most frequently-used one by Fokker was the 225/224 variety of the septimal schisma, allowing 7/4 and 225/128 to be perceived as being interchangeable with each other.

    In Fokker's lattice theory, the spanning of lattice regions by these unison vectors would demarcate a boundary of a periodicity block.

    [Paul Erlich comments:

    That language is a little strange -- I'd simply say, the unison vectors divide the lattice into regions called periodicity blocks.]

    [from Joe Monzo, JustMusic: A New Harmony]


(to download a zip file of the entire Dictionary, click here)

  • For many more diagrams and explanations of historical tunings, see my book.
  • If you don't understand my theory or the terms I've used, start here
  • I welcome feedback about this webpage:
    corrections, improvements, good links.
    Let me know if you don't understand something.


    return to the Microtonal Dictionary index
    return to my home page
    return to the Sonic Arts home page