Are there people who enjoy hearing music in the rain? There may be a few; at least, there were a few who stayed on the lawn at Wolf Trap last night after the rain began, even though they didn't have to.

The occasion was the Wolf Trap Opera Company's annual showcase -- one of the season's notable bargains, not only because you hear a bright young group of singers that probably includes some stars of tomorrow but because a $5 general admission ticket lets you pick any seat you want, inside the Filene Center auditorium or out on the lawn.

The best moments tended to come mostly in music of the bel canto composers and Mozart -- the kind of music for which this summer's singers were recruited, with a season made up of two Rossini operas and "The Magic Flute."

Outstanding work was heard in excerpts from "The Barber of Seville," "L'Elisir d'Amore," "Don Pasquale," "The Abduction From the Seraglio" and "Don Giovanni." From later operatic repertoire, there was an excellent performance of a duet from "The Merry Widow" and enjoyable duets from "Tales of Hoffmann" (the barcarolle) and "Madama Butterfly" (the flower duet), but these made less of an impression. The great trio "Soave sia il vento" from "Cosi fan tutte" began with intonation problems and never really got together at the level it deserves.

Among the singers who stood out, tenor John Daniecki has the lightness, clarity and agility needed for such roles as Almaviva in "The Barber of Seville" and Nemorino in "L'Elisir d'Amore," both of which he sang with distinction last night. He also has a substantial comic talent, which is not quite so rare as his vocal quality but is seldom found together with that kind of voice. This summer, Wolf Trap has two bel canto tenors. Gregory Cross also sang a bit of Almaviva's music and joined soprano Laura Lamport in an exquisite performance of the duet "Tornami a dir che m'ami" from "Don Pasquale"; he did not show the same kind of comic talent (the material was not right for it), but with a voice like his he needs nothing more.

A third tenor, Charles Workman, beautifully styled the "Kleine Pavillon" duet from "The Merry Widow" with soprano Angela Randell and performed impressively with Lamport, Cross and Randell in the Act 2 finale of "Abduction." It is very rare to hear three young tenors of this quality singing in one company.

Less rare but still impressive is the coloratura quality of Lamport, who also has an excellent sense of style and should make an impressive Queen of the Night in "The Magic Flute." Heidi Jones sang well in the "Hoffmann" duet (with Tichina Vaughn) and in the trio "Ah, taci, ingiusto cor" from "Don Giovanni." Richard Zeller and Henry Runey exchanged the roles of Don Giovanni and Leporello in different segments of this opera and seemed equally at home (without singing any of the trditional show-stoppers) in either role. Good, if not spectacular, singing was also heard from mezzo-soprano Phyllis Pancella and bass-baritones Kelly Anderson and Richard Bernstein.

Conductor George Manahan led well-balanced performances throughout and gave his fine little orchestra a chance to sparkle in the "Barber of Seville" Overture at the beginning. It seemed odd to have a stage director listed in the program for a concert performance, but the hand of director George Mattalino was clearly and cleverly evident in "The Barber of Seville, "Don Giovanni" and "L'Elisir d'Amore," though there was not much he could do with some of the other material.