The local duo NUMBER NONE refer to their albums as “annual retorts,” echoing the title of Throbbing Gristle’s Second Annual Report, and like that group they’ve recorded plenty of doomy soundscapes. Compared to TG’s cruelly analytical provocations, though, Number None’s sharp-edged feedback formations, layered field recordings, and melancholy acoustic ruminations have been naive and insular, happily absorbed in themselves; Chris Miller and Jeremy Bushnell have plunged into their varied sound worlds like kids who’ve just learned how to jump off the diving board. But on Urmerica, their fourth and most powerful disc (on their own Rebis label, like the others), Miller and Bushnell look up and regard the world around them–and their response is dread and revulsion. In “Suggestion for a New National Anthem” a remorseless lawn-mower-like roar cuts down the sonic subtleties of a funeral dirge, and in “Secret Handshake, Hidden Hand” flickering frequencies gather around a fundamental drone like a pitiless insect swarm.

Louisville guitarist KEENAN LAWLER has discarded the signal processors that were integral to his music three years ago, when he made his previous trip to Chicago–these days he plays his National steel resonator guitar acoustically, with a slide and a selection of bows. “Life Expectancy of a Rose,” from the new compilation Strands Formerly Braided (Music Fellowship), mimics the structure of a Carnatic raga, rising from a languid melodic exposition to a thrilling climax awash in overtones.

MIKE TAMBURO, a Pittsburgh guitarist who used to play Sonic Youth-inspired instrumentals in Arco Flute Foundation, loses the drums and adds heaping helpings of Americana and loop-based minimalism on his new solo album, Beating of the Rewound Son (Music Fellowship). It’s not terribly original, but it’s nice.

Tamburo headlines, Lawler plays second, and Number None opens. Tue 8/16, 7 PM, Black Spot Gallery, 2315 W. Huron,, $6 requested donation.