Not to be confused with the lugubrious metal duo of the same name, OM aka the Swiss quartet of saxophonist Urs Leimgruber, guitarist (and "devices") Christy Doran, bassist (also plus "devices") Bobby Burri and percussionist Fredy Studer spent 1972 to 1982 in a heavy investigation of free jazz-rock for ECM records, then scattered to other projects before the fire could die (that so many acts of this time would have done the same). While their bio notes that they found an audience with (Jimi) Hendrix and Coltrane fans, one can imagine the band's disciples were the small crowd who, instead of heading for the bar during the "weird" spots, held fast, wide-eyed and rapt during the sprawling feedback bursts and supersonic atonal sprints of said artists (those who make it through 20-minute Can tracks, The Song Remains the Same era Jimmy Page solos and Ornette Coleman's catalog are also likely candidates).

But don't let this depiction frighten you into thinking Willisau fits anywhere near the Medeski, Martin & Wood, Pat Metheny or latter Weather Report bin: the album is a frayed, genre-splitting stomp around the fringes of what "fusion" is supposed to say. OM begins the twelve-part disc with spoken disassociated word clusters, grunts, shouts and tongue-twisters in various languages, moving to coos and whistles as Burri ripples with a simple two-note ostinato and Doran considerately bruises his soundboard and amp. They bustle in this fashion, moving alone-together with independent fragments that display a mastery of both wood-shedding techniques and multifarious creativity (unfortunately, that sentence will have to do, as a comparison to peers versus sounding wholly individual and descriptions of each man's awareness of past, present and future music could fill tomes). Sixteen minutes in ("Part IV"), they thrust into a sudden nefarious, neck-snapping groove. Leimgruber and Doran anxiously unwind into a maniacal duet while Burri and Studer create thumping, crashing accents and meter shifts to circumvent the idea of rest (in other words, do not call it a "vamp"); after an extended attempt by Leimgruber and Doran to out-loud each other, all ease back to their cosmic corners and resume textural research. Predictably, the group does this back-and-forth several times, but the routine never falls into stagnancy — nor do you wish "make up your minds, screw around or rock". The proud spectacle of colors and orchestration is increasingly more brilliant, and each return is either more out there or tighter and/or nimble than the previous.

The members of OM obviously haven't spent the last 28 years on a couch with spoons in buckets of bon-bons (each boasts a discography that requires page scrolling), and this reunion proves that a hiatus is sometimes needed to nurture a band's most fiery, masterful work. Glory days will pass you by, my ass.