The Cambridge History of Twentieth-Century Music, Edited by Nicholas Cook & Anthony Pople

So what do we mean by modern music?

Quietly, we may be crossing some kind of Rubicon. Previous histories of 20th-century music have taken it for granted that this means "contemporary classical", with the emphasis on modernism. Then, in 1995, Oxford republished Paul Griffiths's classic study under the title Modern Music And After. It was clear something had changed. But when Simon Rattle called his Channel 4 series Leaving Home, those departures were seen as enrichments rather than a retreat from a hegemonic tradition.

Quietly, we may be crossing some kind of Rubicon. Previous histories of 20th-century music have taken it for granted that this means "contemporary classical", with the emphasis on modernism. Then, in 1995, Oxford republished Paul Griffiths's classic study under the title Modern Music And After. It was clear something had changed. But when Simon Rattle called his Channel 4 series Leaving Home, those departures were seen as enrichments rather than a retreat from a hegemonic tradition.

Now this Cambridge History has arrived, with a keen sense of its own importance as "the first appraisal" of 20th-century musical developments "from the vantage point of the 21st". Its pluralist narrative finds room for pop, jazz and easy listening alongside classical mainstreams and avant-garde orthodoxies. The non-interventionist stance makes for lively debate between contributors, reflecting the revisionist brand of musicology where the importance of any musical culture must be constantly contested. It's a brave undertaking, since any publication that places Furtwängler next to Peter Gabriel risks charges of incoherence or worse.

The substance of earlier inquiries is present and correct, except for Bartók, here "reduced to a series of cameo parts", as the editors admit. David Osmond-Smith's account of the beginnings of modernism is taken up by Richard Toop as 1950s rationalism gives way to the 1960s uncertainty. Finally, Alastair Williams brilliantly dissects the problems caused by the ageing of a music based on constant change.

The moderate wing is represented by Arnold Whittall's authoritative chapter on Britten and Shostakovich. Robert Fink finds the heirs to that tradition emerging from the post-minimalism of Adams, Glass and Reich. His fashionable conclusion that the mainstream has now moved into "ambient and electronic dance music" won't please everyone and, as the timeline nears the present, it becomes easier to carp. Dai Griffiths, faced with the impossible task of summarising 30 years of popular music, all but ignores the impact of dance music.

The global perspective is encouraging: chapters on the interfaces between Western music and others, and on Africa, remind us that the study of music must broaden its horizons to remain legitimate. But were the editors sufficiently aware of the risk of throwing out our own cultural baby with the bathwater?

The rock-influenced US composer Christopher Rouse (not in the History) put it this way: "I'm not going to talk about rock'n'roll any more. It doesn't need my help. It's not that I no longer like that music, but I feel the wagons have been circled, and I'm going to stick with my high-falutin', élitist, dead white European male brethren and, if necessary, go down fighting."

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