The tricentennials of Bach, Handel and Scarlatti have inspired not only a fresh batch of recordings of existing works, but, in Handel's case at least, the discovery (or reconstruction, if you will) of a new piece. Saturday night the Springfield Symphony Orchestra, joined by the Maryland Handel Festival Chorus and five outstanding soloists, premiered "The Roman Vespers" locally at St. Matthew's Cathedral.

The sterling performance and its warm reception owed a great debt of thanks to the eminent musicologist H.C. Robbins Landon, an 18th-century music specialist perhaps best known for putting the Haydn catalogue in order. From a 1959 essay by James S. Hall proposing that Handel composed a large two-part vesper service in 1707 for Cardinal Carlo Colonna's church in Rome, Robbins Landon reinvestigated period diaries and manuscript scores, piecing together an unpublished motet and antiphon with published Handel psalm settings and instrumental portions to restore "The Roman Vespers."

He confesses that his arrangement of part one (a cantata overture, motet, antiphon and psalms) is somewhat "free" while part two (a sonata for organ and orchestra, psalms and a "Salve Regina") follows the order prescribed by British manuscript scores. On first hearing, one must agree with these remarks, for part two seems more unified. Nevertheless, Robbins Landon's architecture can scarcely be faulted; right down to the keys used (beginning and ending in G minor) he leaves no doubt about the legitimacy of his (and probably Handel's) cyclical conception.

Because of the cavernous acoustics of St. Matthew's Cathedral, "The Roman Vespers" required some readjustment on the listener's part at first. Aside from gobbling up some of the vocal soloist's power, the cathedral's sound delay created the same visual impression as a foreign movie dubbed in English. However, this aural situation benefited the chorus by providing a reverberant, dramatic edge, especially to the "Dixit Dominus."

Handel entrusts his most expansive vocal segments to the sopranos, and Kaaren Erickson and Judith Blegen were both glorious. Erickson gave stunning accounts of the hitherto unpublished motet, "Saeviat Tellus" and the antiphon "Haec est Regina Virginum." Yet her finest moment came in the "Salve Regina," when she drew out the words "we sigh" against a sparse string accompaniment. Erickson and Blegen blended evocatively in the "Dixit Dominus' " "De torrente in via bibet."

Tenor Grayson Hirst, baritone David Evitts and countertenor Drew Minter, while less prominent, were no less impressive. As a last-minute substitute for John Ferrante, Minter purportedly sight read his part, though one would never know it from his assured projection and crystalline enunciation, which tamed the echo-chamber sonics.

Conductor Robert Gutter and the Springfield Symphony provided an immaculate ensemble throughout with seamless transitions and a well-balanced attack. Oboist Frederic Cohen and cellist Barney Lehrer stood out for their insightful play in support of the sopranos.