Jo Jena‘s Rhythm ‘n’ Drones, from the test tube netlabel, could just as easily exchange that “‘n'” for an “or.” The album’s eight tracks are divided in two: half are titled “Rhythm I” through “Rhythm IV,” the other half “Drone I” through “Drone IV.” A standard rhythmic track, like “Rhythm II,” features crafty guitar counterpoint that evades a strict downbeat by suggesting many. To Jena, it turns out, this is what constitutes rhythm: something sharp and hard, of definite shape and pulsating with momentum. Other variations include scraped percussion and a moire pattern of pizzicato action, but the real keeper, “Rhythm III” (MP3), sounds, of all things, like ersatz African juju pop music, complete with sour bent notes. Jena’s drones are equally varied, including the industrial hum of “Drone I,” which is textured with scrapes, and the orchestral-sounding “Drone II.” The album is organized in a kind of broken symmetry: alternating rhythms and drones three times, and then reversing for the final pair. According to a note on Jena’s site, jo-jena.com, “‘rhythm ‘n’ drones’ consists of eight pieces which should be listened to without (even very short) pauses.” Get the full set at the test tube site, monocromatica.com/netlabel, and listen to them as you wish.