The Hercule Poirots and Miss Marples among us will enjoy the odd mystery surrounding the creation and alteration of the great masterwork which leads off this release. Published only after Mozart's death, the score to the D ma­jor String Quintet bears a tantalizing phrase: "composto per un amatore ongarese." Who was the anonymous "Hungarian music lover"? Can it be the same enthusiast mentioned anonymous­ly by the publisher Artaria (in his adver­tisement of May 15, 1793) as having made such "very urgent entreaties" of the composer that not only the D ma­jor Quintet but the E-flat major as well resulted?

The answers to these questions are unknown at present. We do know that Mozart almost never wrote "for the drawer," but for specific performances or when commissioned. Whether one person could have been responsible for two incredible works composed four months apart is anyone's guess.

The dates come from Mozart himself: December 1790 for K. 593; April 1791 for K. 614. There the information leaves off. Perhaps the "amatore ongarese" was a figment of an imagination aimed at creating sales of the printed scores. Flights of fancy for purposes of salesmanship were as much a part of marketing a product in the 18th century as they are now. In any case, there is more to the mystery.

Someone altered Mozart's score! The finale to K. 593 was rewritten, we know not by whom. Until recently, Mozart was believed to have done it. Was this editorializing the result of a rehearsal or performance? Whose criticism inspired it? Could it possibly have been a well-­meant attempt to render the unadorn­ed original somehow smoother, more palatable? Readers can form their own opinion, thanks to this new release, for included in it are both versions of the finale--done to a turn. The differences are noteworthy.

With regard to K. 614, Mozart's last major chamber work, it must be observ­ed that, contrary to the popular belief that whole masterpieces simply occur­red to Mozart and he had only to copy them out of his head, its seamless effect did not come easily. The composer, whose death lay only eight months away, made "several attempts" to com­plete the score. Could the problem have been its esoteric, even futuristic handl­ing of thematic relationships among the movements? Mozart was quite beyond his contemporaries in works such as this: in a world of his own sublime creation.

Biographer Arthur Hutchings notes curiously that "many professional musi­cians seem to think that the last of the quintets, the E-flat, K. 614, is the finest." While praising it as "hauntingly beautiful and original," he is quick to cite an extraordinary quality of K. 593: The slow movement of this work con­tains the most astounding piece of polyphony in the whole classical epoch, the kind of counterpoint which Beethoven could never have achieved. He adds that it all sounds euphonious and facile, yet it incurs ingenious "vocal scoring" and a movement of parts through the boldest discords. He is right, of course. And this only deepens the mystery.