One of the founders in the 1970s of the so-called "spectral" school, Gérard Grisey demonstrated his musical theories most completely in his vast "Les Espaces Acoustiques"; but he also composed a number of instrumental solos and small ensemble pieces that indicate how his nascent ideas developed. This 2005 release from Kairos presents a selection of these chamber works, ranging from the early "Charme for clarinet" (1969) to "Stčle for two percussionists" (1995), composed three years before Grisey's death. These compositions, along with "Tempus ex machina for six percussionists" (1979), "Solo pour deux for clarinet and trombone" (1981), and "Anubis-Nout for contrabass clarinet" (1983), are nothing short of theoretical investigations: of sounds as events; of the variable resonances of overtones in acoustic space; and of the conflict between objective, chronometric time and psychological time, as perceived by performers and listeners. These musical problems are heady stuff, not easily grasped by lay listeners, let alone by those familiar with Grisey's experimental procedures. As a result of the difficulties presented in this cerebral music, much of this recording will seem scattered, meandering, and dull for long stretches. Without some theoretical grounding -- never mind the poetic liner notes that contribute little helpful information -- this CD is rather hard to understand or like; and while these pieces are undoubtedly valuable for scholars to comprehend Grisey's work as a whole, they are not sufficiently eventful or colorful for pleasurable listening. The performances by clarinetist Ernesto Molinari, trombonist Uwe Dierksen, and Ensemble S are competent, and Kairos' audio is expertly engineered, so if abstract and abstruse music appeals, this disc will adequately fill the bill. Blair Sanderson, All Music Guide