The post-war avant-garde required an entire cadre of virtuosi to bring into the world the great complexities of innovations.In perticualr the creative focus on the solo unaccompanied work was an intense point of concern and interest. Part of this was labeled "the new virtuosity".And pieces owe their creation to the overwhelming performative skills,persistence and imagination of these soloists.There was not much precedent emamating from the vigours of modernity, in fact there was no unaccompanied work for the trombone or tuba, or french horn until well into the Twentieth century.These virtuosi are too numerous to mention, but certainly William O.Smith was the first to explore multiphonics on the Bb Clarinet in the early Sixties, Bertram Turetsky also found the hidden timbres in the contrabass, almost like a sonic archeologist picking and scraping through the historical baggage of their instruments. Vinko Globokar(avant-garde, and Albert Magelsdorff(free jazz) in Europe both on trombone as well, but their counterpart here in the States was Stuart Dempster, an incredible virtuoso. Composers wrote for him as no other,once they heard him play.He had a real innate gift for the avant-garde, I recall him crawling around the floor of the stage striking matches to create extended sounds in John Cage's "Solo for Sliding Trombone",disassembling the trombone blowing into all the remaining tubes to great mysterious affect. He had premiered dozens of works throughout the Sixties and Seventies by distinguished American composers, Ben Johnnston, Robert Erikson, Jacob Druckman, John Cage, and Luciano Berio his Sequenza #5 which was the high water mark, a piece that today is a standard staple in the literature. Dempster solidifies all this experience in this book actually the first, the premiere work to discuss,multiphonics(singing and playing simulataneously),muting, and extended techniques for the trombone. This instrument has come light years transcending its cumbersome constitution as inhabiting the backwalls of the orchestral placement to enter for a choral like chord. No, now however through the eyes and ears of Dempster's imagination it has become now a complete universe of sound. Chapters here include very practical examples of all these techniques citing the master works of the literature. Although out-of-print I wish the publishers would attempt to update these incredibly valuable works, Phillip Rehnfelt has one on the Clarinet, Bertram Turetsky on the Contrabass, and one on the Flute, a compendium on multiphonics. Dempster now has extended his creativity into the fascinating world of the aborginal tribal instrument (the down under world) of the didjeridu, a long hollowed-out wood tube done by termites in its original form. There is also a plastic version.