Shortly afterwards a facsimile of the existing manuscript pages was published, in a limited edition of 1000 copies. It is perhaps surprising that Mahler's widow, Alma, decided to allow the publication, in view of the highly visible, anguished comments scrawled over it by the composer, aware that his wife was having an affair with architect Walter Gropius -- later to become her second husband.

And there the matter appeared to rest, except that anyone looking at the facsimile closely could clearly observe that Mahler had, in fact, completed the symphony, in the sense that there was a single uninterrupted musical line throughout; in places in Mahler's short score there was only a single part indicated, with no hint of orchestration, but there were (almost) no gaps.

In the 1940s, Mahler enthusiast Jack Diether tried, without success, to get a number of well-known musicians who admired Mahler (including Benjamin Britten, Dmitri Shostakovich and Arnold Schoenberg) interested in completing the work from the manuscript. As many readers will be aware, English musicologist Deryck Cooke did exactly that: fleshing out the short score and completing the orchestration. His "performing edition," as he was always careful to call it, was first performed in 1964, revised in 1972 and has been recorded a number of times. (A broadcast talk in 1960, including a performance of his first thoughts, which still had some gaps, brought a ban from Alma until 1963, when she rescinded it and also made more manuscript pages available, which had not been in the 1924 facsimile.)

But Cooke was not the only, nor the first, to study Mahler's manuscripts and attempt a completion. In fact four men, all musicologists, have completed performing versions of Mahler's Tenth: the others are Joseph Wheeler, Clinton Carpenter and Remo Mazzetti. Wheeler's is the last to appear on disc, but this new issue from the Colorado MahlerFest (an organization which exists to put on an annual festival in Boulder at which all Mahler's symphonies are performed, one each year -- they are now in their second complete cycle) proves to have been well worth the wait.

Now that all four completions have been recorded it is possible to compare them (at least aurally, scores are only available for the Cooke to my certain knowledge), and one thing quickly becomes clear: their similarities are far greater than their differences. In 1963, when the octogenarian Alma was finally persuaded to listen to a tape of Cooke's initial broadcast, she was so moved that she lifted the ban and remarked that she "had not realized there was so much Mahler in it." The essential similarities between the four "completions" serve to underline her point. But the four men differed in the degree to which they were prepared to go beyond exactly what Mahler left on the page in order to fill out the harmony, etc. In this regard Wheeler turns out to be the least "interventionist" (behind Cooke, Mazzetti and Carpenter, in that order). What this means in practice is that Wheeler's version of the score is leaner in sound and that, to many ears (mine included), makes it the closest of the four to Mahler's late orchestral sound, as found in Das Lied von der Erde.

The story of the preparation of the parts from Wheeler's manuscript -- of the team of musicologists checking them against each other and against Mahler's own hard-to-decipher writing in a race against the clock -- would make an adventure novel in its own right. Suffice it to say that Robert Olson's role as editor was, according to those in the know, a vital one. What makes this new disc so desirable, though, is the performance. Olson has been conducting at the MahlerFest since he founded it in 1988. His dedication to and love of Mahler's music have never been in question. His own stature as a conductor of Mahler was first demonstrated to the outside world on the MahlerFest CD of the massive Symphony No.8, which was issued a few years ago. This new disc reinforces the positive impact of that one; in fact the performance is, if anything, even finer. Even without the appeal of hearing Wheeler's version for the first time, I'd want this Mahler 10 in my collection; it is that good a performance.

The recording need make no apologies, although there are the inevitable minor glitches of capturing a large ensemble on the wing. The orchestra, which only plays together once a year (at the festival), plays with enormous dedication and, if they are not quite the Berlin Philharmonic, they make up for it with apparently limitless enthusiasm -- and they are, after all, only playing because of their love for Mahler's music. The CD booklet is a mine of useful information, in fact it is a model of its kind. I really can't say enough good things about this disc.

Wheeler is fortunate to have found advocates as persuasive as Olson and the MahlerFest orchestra; unlike the only recordings of Mazzetti's (Slatkin on RCA) and Carpenter's (Fabermann on Golden Strings) versions, this performance is good enough to judge the score by.

Indeed, as I hope I've made clear, it is a great deal better than that. Mahler-lovers will need no prompting, this is a self-recommending issue. For those unfamiliar with the Tenth, I think this is now the place I'd recommend starting. The disc is available direct from the Colorado MahlerFest at http://www.mahlerfest.org