Shake, Rattle and roll

LEAVING HOME: A Conducted Tour of 20th-Century Music with Simon Rattle, by Michael Hall, Faber pounds

Simon Rattle's Leaving Home is a superb enterprise, but it presents a familiar irony. The television series may be repeated just once; the accompanying CDs will be available in the shops while the series is on the air. What will last longest is the associated book - yet seldom has a book come more hobbled by its dependent, spin-off status. This is not just a matter of the maestro's patronising foreword, nor of the author's defiant decision to fill the gaps in the maestro's survey. It lies in a design-tic that accosts you on almost every page. While the main text pursues its course, little gobbets in bold type float in the margins - soundbites from the television script. When these are pertinent, you wonder why they are not woven into the text; when they are not, you wonder at the editorial impudence.

Yet Michael Hall has pulled off a major feat. His account may suffer at times from a potted-history tone, but it makes more sense of 20th- century music's quixotic journey than anything else so far. At every stage, he seeks to explain rather than judge, and - given the esoteric nature of his material - that is enough. Even the title calls for careful unpicking: the "home" left by Schoenberg and his followers was a technical concept as well as a haven of stability. The "home key" was the basis for the tonal system on which Western music rested for 300 years: it was the key from which each work started, and to which - after a divagation - it unwaveringly returned. Schoenberg's system, in which each note was given democratically equal importance, denied both the home-key idea and the notion of progress towards a pre-ordained goal. This was, as Hall puts it, "a style to capture the fullness of the moment".

Following the television series, Hall covers tonality and also rhythm and orchestral colour, on which his essay is masterly. He demonstrates how prophetic Schoenberg was when he proclaimed that melodies could be made of tone-colour, as well as out of pitch. He shows that "depth of focus" can apply to an orchestra as to a camera: Monteverdi, Haydn and Mozart all capitalised on the resonance of different instruments to suggest distance and dramatic effect. Debussy deployed his instruments in L'apres- midi d'un faune for a similar purpose, as though lifting a curtain to reveal a landscape receding to the horizon.

As Hall explains, loudness is not the criterion by which we judge the distance of a sound: the criterion we unconsciously use is the degree of noise in a sound, the amount of "deformation" - through bouncing off a variety of surfaces - mixed in with the pure note itself. He traces the progressive realisation of this fact through the work of Stravinsky, Stockhausen and Messiaen. And he shows how the breakthroughs of the Second Viennese School - Schoenberg, Webern and Berg - led to the cerebral excesses of the Darmstadt School, and Boulez's clinical empire in Paris.

From the cryptic games of Alban Berg (whose works were full of palindromes and secret personal references) to the preposterous extravagance of Stockhausen's japes (four helicopters for an airborne string quartet), this account faithfully reflects "serious" music's increasing estrangement from ordinary life. At one level it's the story of a battle between those who want to control everything (like the mathematician-composer Milton Babbitt) and those who want to control nothing (John Cage leaving his compositions to be determined by dice). At another level, however, it's the spectacle of a communal suicide. Hall doesn't put it as starkly as that, but his introduction contains a revealing remark: "Nothing fundamentally new has emerged since 1973."

Is that really true? And if so, by what criterion? The trouble with Hall's criteria is that they are rooted in the Modernist - ie very old-fashioned - intellectualism of the first half of this century. He tops and tails his book with a whinge: the economic recession has put composers on the defensive; too few listeners want to be "challenged"; too many want music to be "a palliative or a means of escape". There is no room, in this dessicated definition, for music that heals and consoles, delights and inspires. If we are not "progressing", we must be "in retreat towards Romanticism", which is where Hall sadly concludes Britten and Tippett headed after the war, followed by reformed revolutionaries like Henze. When he does try to pinpoint today's key composers, he writes without conviction, as though he knows the show is over.

But it's not over. It has moved beyond the confines of the Western avant- garde, and its future lies among the myriad styles and forms going under that catch-all banner, "world music". Something did happen in the Seventies, of deeper significance than an economically-induced loss of nerve among a small bunch of creators in London and New York. The public - despite desperate prodding by the Arts Council and the BBC - simply lost interest in their game.