American ensemble, Banchetto Musicale, under the direction of Martin Pearlman, recorded Handel's ''Allegro, Il Penseroso, ed il Moderato,'' (Arabesque 6554-2, two LP's) set to two poems by the young John Milton with a third, markedly less distinguished, text by Charles Jennens rounding out the work. Banchetto Musicale is a Boston-based group that plays early music on original instruments. Their playing is stylish, if occasionally a little too self-consciously ''correct'' and considered for this taste; the Puritan spirit dies hard. The recording is distinguished by the contributions of some bright young soloists - the sopranos Nancy Armstrong and Sharon Baker, the mezzo-soprano Mary Westbrook-Geha, the tenor Frank Kelley and the baritone James Maddalena; Mr. Pearlman has provided succinct, intelligent notes.

Boston Baroque, conducted by founding music director Martin Pearlman release an all-Mozart release Mozart: Arias for Male Soprano. For the project, which marks their 20th release on Telarc, the ensemble has united with the fascinating American vocal artist Michael Maniaci, a true male soprano, in their first recording together and his first solo recording with orchestra. This recording of "firsts" is also the premier recording of Mozart's arias for the castrato voice that gives audiences the opportunity to hear it as Mozart heard it: sung by an artist not only with soprano range, haunting vocal color, and brilliant coloratura, but also with male vocal power. The disc contains arias from Idomeneo, Lucio Silla, and La Clemenza di Tito, as well as the beloved motet Exsultate, jubilate. The recording is rounded out with two brilliant orchestral numbers, the overtures to Idomeneo and Clemenza.

Even though the 1792 completion by Franz Xaver Süssmayr is regarded by many as the standard performing version of Wolfgang Amadeus Mozart's unfinished Requiem in D minor, several musicologists have tried their hands at alternative versions with varying degrees of success. In his masterful edition, Robert Levin preserves all that is reliably Mozart's music, substantially recomposes the inept Osanna fugue, and here and there touches up faulty harmonies and clumsy orchestration. Levin also replaces the cadential close of the Lacrimosa with a completion of Mozart's sketches for an Amen fugue, a feature of this completion that some listeners may find startling, but sufficiently Mozartian and ultimately satisfying as a solution.

The most popular opera of Gluck might be Orfeo ed Euridice, but this one, Iphigénie en Tauride, is probably his most dramatically involving. It is about familial love and deep friendship and, as such, lacks the usual "love" music and interest. But the waters here run deep, and Martin Pearlman and his singers plumb those depths. Christine Goerke's Iphigénie is dignified, rich with expression and beautiful tone. Almost no less good is the Orestes of Rodney Gilfry, who uses his high baritone with intelligence and ease, singing tenderly when needed and explosively at other times. Vinson Cole brings grainy, expressive tenor to the role of Pylades firmly and effectively; and Stephen Salters, as the villainous Thaos, might sing coarsely, but it suits the character.