ven in the ultra-minimalist world of Sachiko M, this disc is particularly minimal. It comes packaged in a plain white cardboard folder with nothing on it but the names of the performers and the instruments they play. Sachiko’s sine waves are of course familiar to anyone who’s been following electro-acoustic improv lately, and indeed the disc starts out with a single suspended tone, high-pitched and completely still, the sonic equivalent of a totally placid pond. But Sean Meehan is the relative unknown here, and his snare drum and cymbal—the ultimate minimalist drum setup to parallel Sachiko’s reductionism—provide an interesting complement to his partner’s glistening tones.

Of course, there’s nothing about Sachiko’s wavering, high-pitched frequencies that suggests she’d be a good working mate for a drummer, but Meehan’s techniques on his small kit are far from conventional. Rather, he uses the typical percussionist’s extended techniques—rubbing, scraping, sliding—to produce creaky, rattling drones that are a surprisingly natural analogue to Sachiko’s own sounds. For much of this disc, Sachiko is the cold, hard center of the music—her tones are constant and stable, rarely changing and never changing drastically—while Meehan works around her, adding to, complementing, and occasionally subverting his partner’s central drone.

On the first track, Meehan lets Sachiko’s high tone lie untouched in the still air for an uncomfortably long time, giving the album’s opening an ascetic aura that’s appropriate to two such austere improvisers. When he does finally add his own voice to the proceedings, it’s in the form of a few peripheral cracks and rattles that only slightly warm the chilly stasis of Sachiko’s sine wave. The second track (which, at 18 minutes long, comprises nearly half the album) is marginally more eventful; the first half is dominated by another nearly steady tone, but Meehan adds walloping drones scraped out on his kit, and the organic roughness of his shaky tones periodically overwhelm and drown out the impassive stillness of his collaborator. But when his drones subside again—as they almost inevitably must, coming from such tenuous and human means—Sachiko’s tone emerges from the other side of the disturbance, unperturbed, as immoveable as a glacier. On the second half of the track, Sachiko adds more peripheral twitters and oscillations to her sound, and the music begins to morph from an antagonistic duel into a responsive conversation, the two musicians trading understated comments in their own secret language of tweets and groans.

This becomes the common language for the rest of the disc. The third track emerges from an unsteady, hissy silence with barely audible pops and momentary blips of sound, and at this point it’s hardly clear who’s making what sound—a testament, more than anything, to Meehan’s ability to sound completely un-drum-like. This is music hovering on silence, with enough space between each interruption to make every new sound refreshing and momentous. By the fifth track, however, Sachiko and Meehan have reached a near-perfect level of communication. The track begins with both musicians blending their very different drones into one monolithic hum full of nuance and interplay between the multiple layers. It’s still difficult to distinguish exactly where each player’s contributions begin and end, though it’s fairly obvious that Meehan is providing the scraped outer drone that sounds nearly like a sustained violin crescendo, while Sachiko is responsible for the dense tinnitus ringing at the drone’s center.

Finally, the album closes with just under a minute of what sounds like Meehan solo, extracting a tortured cry from his drum kit—perhaps as a raw counterpoint to Sachiko’s pristine sole tone that opened the album.