“Just intonation”, according to the liner notes, is “a tuning system derived from the Harmonic Series, in which all the intervals of the system can be represented by (preferably small) whole-number ratios.” Most non-Western music—e.g., Japanese classical, or ongaku—uses this type of tuning, and so do everything from Gregorian chants to barbershop quartet harmonies (again, so it says here in the notes). That doesn’t mean the music in The Harmonic Series sounds like any one of those things, but that might give you an idea of how left-of-center it sounds.

The collection’s comprised of a good mix of conventional and unconventional instruments—from simple piano to experimental bowed instruments, all the way into pure electronic composition using Max/MSP. Many of the pieces revolve around resonances and overtones. Michael Harrison’s “Tone Cloud II”, Pauline Oliveros’s “The Beauty of Sorrow” and R. Keenen Lawler’s “Bow Shock” all work this way, the latter two sounding a great deal like the sort of wall-of-drone that Keiji Haino laid down in his 21st Century Hard-y Guide-y Man album. Duane Pitre’s “Comprovisation [sic] for Justly Tuned Ukelin no. 1” brings to mind another composer who made alternate tonalities one of his mainstays: Harry Partch. Zachary James Watkins’s “Country Western” mixes only instruments in Just Intonation but vocalizations and electronics, both improvised and composed (although you have to listen closely; some of it breezes right past you in the mix). The only real letdown is Charles Curtis’s “Stanzas Set Before a Blank Surface,” which sounds more like the aforementioned Haino doing a feedback soundcheck than anything else.

If I haven’t made it clear yet, the one thing that is most consistent from track to track is the ethereal, aching beauty of the music. Put aside all the theory, and what you’re left with is quite haunting and charged with unforeseen emotion: you don’t expect this stuff to affect you as much as it does. Let’s hope Important Records curates a few more forays into this territory.