New Yorker music critic Alex Ross's recently released book, The Rest is Noise: Listening to the Twentieth Century (Farrar, Straus and Giroux, $30) is an in-depth and entertaining study of 20th century classical music.  It describes the lives and work of composers from Mahler and Strauss all the way to contemporaries such as Kaija Saariaho, Tan Dun, and Sophia Gubadulina, with an incredible depth and breadth of knowledge not only about music, but also about history more generally.  It as been well reviewed (and rightly so) with names of famous readers expounding its greatness on the back cover: if it is promoted by as varied stars as Björk, Osvaldo Golijov, Emanuel Ax, and Richard Taruskin, it must be good.  But with all these reviewers, and the scope of the work, it is hard to figure out who this book is for, why he wrote it, or whether there is anything particularly significant to be found in it.Part of the answer to this question can be seen by the sorts of details Ross centers on.  He makes a great effort to pick out notable pieces of music and tries to describe them with an analyst's attention to detail, translating complex musical ideas into a generally readable instruction.  Overall, these analyses are very astute, approachable discussions of the inner workings of certain compositions, though at times they fall into overly stylized language and the problematic talk of metaphors and evocations without which, admittedly, non-technical music analysis would come to no conclusions.  In this way The Rest is Noise reads like the program notes to the biggest pieces of the century.  But program notes are things to read when the concert itself gets boring.  Is this all Ross is trying to accomplish?  When the music ceases to be clear in its meaning, as is the case with most of the music Ross discusses, the critic must step in and connect it with real people and events, to give it a meaning in the face of its seeming incomprehensibility.  Accompanied by his blog (of the same title as his book) the reader has access to a large discography for his or her "to listen to" lists, and mentions composers along with their most significant pieces, pieces with which to get a proper taste of each composer.  Oriented toward the unspecialized but educated concertgoer, it is written primarily for the same people who read the New Yorker.  In fact, its Manhattan-centric view of the world (though not unfairly; that is where all the interesting stuff happens) only emphasizes the connoisseur-oriented eclecticism which hovers slightly beneath the prose of the book. Central to the story line are the lives and personalities of the 20th century composers, the men (and a few women) of flesh and blood, as Unamuno would say.  Full of History Channel style trivia, the relationships among the composers - who knew who, who listened to who, who taught who, who lived down the road from who - makes an interesting read and also more soberly documents the connections through which the development of the music proceeded.  Usually these peripheral details seem to be meant as tidbits for popular consumption, interesting facts to quote at cocktail parties.  However, the extreme lack of such details in other discussions of music history are equally problematic and so the biographical, day to day anecdotes and connections serve to entertain the reader as well as to ground the ideas and ideologies at work in the practices of the various composers in a more understandable manner. For this reason, The Rest is Noise is also a valuable book for those with more specialization in music.  Musicians and Musical scholars who have been brought up in another musical historical context entirely, in the ‘music appreciation' class or an introduction to music history, which has its own modus operandi and own narratives, will benefit from the critically examining the lives and thoughts of various composers.  Rather that going through the same interpretations and same material, Ross takes a fresh look at many historical stories, with plenty of primary sources (and for that reason a great bibliographic section) while avoiding some of the more worn anecdotes.  It is notable that, while discussing Strauss, we do not read once about his depicting silverware in music, perhaps the first discussion of Strauss in fifty years not to do so.  The ideas about music also come under Ross's discussion, from the alleged historical inevitability of Schoenberg's music to the political content of music in Nazi Germany, the USSR, and the ‘40s and ‘50s US, or even the sacred nature of music in Messiaen, some ideas are tacitly denied, and some are interestingly sustained. Ross escapes a big issue in his title "Listening to the Twentieth Century" since it avoids naming what sort of music constitutes his topic.  Now, if you walked into Barnes and Noble, most of the music which Ross discusses could be found in the "classical" music section, though there is nothing classical about most of it.  And while Ross discusses the Beatles, the Velvet Underground and a variety of other ‘popular' musical artists, this book reinforces that specific realm of music, nowadays abiding mostly in the academy, of historically conscious, self-involved specialty of writing music to be listened to, thought about, and appreciated.  Even this definition seems lacking; still, it is not all music in the twentieth century to be sure, and this limitation is significant.  Jazz is discussed at times, as well as Rock, but the central focus is this music sometimes called "high," "legitimate," or "classical".  It might be described in the broader sense of music lacking self-evidence. But if there are biases in Ross's work, they are not those biases found in the Twentieth Century itself - which are precisely those biases which the Academic study of music inevitably fall into.  This book is an example of popular research which in many ways surpasses scholarly research through its grounded analysis avoiding impassioned commitment to one tradition or one sound.  But the book does this by forsaking the reason why the academics have such a different method: the investments towards certain traditions it seeks to uphold.  Atonality and the Schoenberg tradition is, for most official music history, the continuation of the modernist classicalism of European ‘classical music.'  Ross speaks of it from a distance, and thereby escapes the predominant understanding of20th century "high" music.  On one hand we have the bitter passion of the academy trying to keep alive the dying tradition out of which it arises, and on the other hand, Ross, his level prose situating this rhetoric along with its music and its time.  Hence the analysis in The Rest is Noise presents a high quality study in which nothing is at stake, unbiased and uncommitted. Yet it is clear that Ross is invested in the music he describes, but not because he says as much or commits to a rhetoric of value.  The investment is at once absent from the text and immanent to the whole work.  The project of the book is no less than to establish the canon of 20th century music, to place in encyclopedic detail those composers significant enough to be known by an educated audience.  While this was tentatively accomplished already for the first half of the 20th century, one strength of this book is Ross's astute awareness of the composers of the last 50 years.  Until now, history had been reserving judgment on these new developments, especially since they are so unpopular.  As Adorno, whom Ross has clearly struggled with, says about modern art, "What has terminated tradition can hardly count on one in which it would be given a place."  Still, Ross gives them a place, perhaps not one which they would have liked, but still better than they could have been given by the largely unappreciative and correlatively unwanted audiences. Music criticism has a tradition of producing excessively scathing, bombastic rhetorical tirades about composers and pieces. With both the music, and the ideas about music, Ross maintains a dispassionate- perhaps we could say Kantian-disinterestedness, which is refreshing after two hundred years of grandiloquence about the horrors and triumphs of certain composers. At the same time, these composers, historical events, and pieces of music are still under debate.  The dust has not settled on the Twentieth century, and in contrast to these debates Ross's tone sounds as close to authoritative as one can get these days. Still, Ross really has only nice things to say about the music - he might even convince some people to actually listen to some of it, which would be good - and his authoritative tone is inclusionary and intended for the betterment of people's general musical reception.  For both those who don't know what to think about 20th century music, as well as for those who already have dealt with some of it, The Rest is Noise provides an entertaining read and a nice resource for approaching the difficult music of the twentieth century.