A member of the Sonic Arts Union, which also included Robert Ashley, David Behrman, and Alvin Lucier, Gordon Mumma (b. 1935) produced perhaps the most challenging electroacoustic music of the 1960s, '70s, and '80s. Along with John Cage and David Tudor, he has written for the Merce Cunningham Dance Company, whose credentials remain almost avant-garde enough to dispel doubts about the terpsichorean possibilities of Mumma's work. This collection does indeed make for difficult listening, and it doesn't immediately inspire structured movement. But Mumma's experiments obtain a stark, bracing beauty. They challenge the listener to resolve contrasts between the found, the composed, the looped, and whatever else strikes Mumma as appropriate.

For example, the signature work here, The Dresden Interleaf 13 February 1945, ties itself to a particular time, place, and event--as does virtually all his music--reproducing the firebombing of that city in the most frightening manner possible: tense anticipation alternates with earsplitting trauma. Like John Zorn, who has commemorated another Third Reich event, Kristallnacht, with deliberately uncomfortable noise, Mumma wants to evoke a visceral response. The original live performance included burning model-airplane engines. The work is meant to be played without a break between two unrelated pieces of classical music--"interleaved" as an interruption similar to that of the attack itself. The limited range of the recorded medium can only partly replicate the physical effect. That is probably why we have had to wait so long for this one CD dedicated to Mumma's music, adopting, as the disc does, the qualities of an archive. As such, however, Studio Retrospect represents an indispensable summation of his uncompromising aesthetic. --Robert Burns Neveldine