Active since the mid-1960s, England's AMM have become an icon of the free improvisational movement. In the spring of 2004, due to personal and philosophical disagreements, Keith Rowe suspended his involvement with AMM, an association that went back to his role as founding member in 1965 (albeit with an almost decade-long disenfranchisement through the '70s). The remaining members, percussionist Eddie Prévost and pianist John Tilbury, elected to continue on as AMM, and this their latest effort. Tilbury, in duo format, becomes a somewhat more active participant than he often was in the trio, forcing the action a bit more than floating atop it, bursting into abrupt Taylorisms here and there in addition to his more delicate arpeggiating. Prévost, for his part, does a masterful job of sinking into the background, coloring the proceedings with precisely the right shadings and accents, staying almost entirely off of the drum set as such, concentrating far more on gongs, bowed cymbals, metal and wooden objects, and other esoterica.