Xenharmonikôn, An Informal Journal of Experimental Music is devoted to all aspects of microtonal and xenharmonic music. XH covers a wide range of topics including:

• microtones;
• just intonation;
• equal and unequal temperaments;
• novel scales and harmonic structures;
• new notation systems;
• keyboard and fingerboard layouts;
• new instrument design and construction; and
• electronic and computer technology, as applied to theoretical and compositional problems in these areas.

Each issue of Xenharmonikôn includes numerous items such as:

• notes and comments from the editor;
• articles and interviews;
• news, announcements, and reports relevant to the xenharmonic community;
• charts, tables, and diagrams;
• musical scores and analyses;
• computer programs;
• reviews of books, recordings, and performances; and
• new product announcements.

Xenharmonikôn was founded in 1974 by John H. Chalmers and is published irregularly. Dr. Chalmers has edited all issues of XH except volumes 9 through 12, which were edited by Daniel J. Wolf. Volume 17 has just been published.

Xenharmonikôn is named after the astronomer Ptolemy’s summary of ancient Greek music, Harmonikôn en Biblia Treia, which translates in English as (On) Harmonics in Three Books, or simply the Harmonics. The prefix xen derives from the Greek word xenos meaning “strange.” The term xenharmonic was coined by Ivor Darreg to refer to music which does not sound like 12-tone equal temperament.