Battles, ‘Gloss Drop’ (Warp)
The second album by these New York math-rockers embraces a dubious formula: subtract exceptional avant-garde guitarist Tyondai Braxton, add…Gary Numan? Yet Numan’s harried, yelping cameo on “My Machines” is a triumphant moment, an experimental outburst both ingenious and accessible. The quintet’s 2007 debut, Mirrored, was proggy, primal fare; Gloss Drop is an immersion in abstract tonalities, with Tropicalia-touched dark minimalism (“Rolls Bayce”), tetchy arrhythmic strings “(Africastle”), and propulsive funk (“Futura”). Braxton’s clever, found-sound loops are missed, but the remaining members’ rampant ideas and inexorable groove keep Battles engrossing.