A few things were missing in the "Cosi fan tutte" presented by Capitol Opera (a new company) last night at the Reston Community Center. It lacked a chorus and orchestra, for example, not to mention scenery.

But let's consider what was present rather than what was absent. The production offered a masterpiece of stage direction that was coherent in concept and clever in compensating for budget limitations. Sometimes a bit too clever, perhaps. But if you must go to an extreme, that's the one to choose. It was sung by voices that were usually pleasant and sometimes compelling. The ensemble singing was generally excellent.

The text was English and, after the usual early phase of vocal adjustment, about 80 percent of the words were intelligible. There have been more lavish productions in which the intricacies of "Cosi's" libretto were less clear.

True, it sometimes looked like a high school senior show. And the voices were not always good; tenor Alfonse Anderson seemed to tire in Act 2 and bass Paul Klingenberg was vocally uneven. But on the whole, Mozart and librettist Lorenzo Da Ponte's frothy concoction worked quite well. If this was not the ultimate "Cosi" (for that, you have to go to Salzburg when Riccardo Muti is conducting), it was a fair way to get acquainted with the words and music.

Presumably, that function -- building new audiences -- is what small opera companies that use only a piano rather than an entire orchestra are all about, particularly in the suburbs. They also give experience and training to young singers; Capitol Opera had two complete casts alternating in this "Cosi."

Two performers stood out last night. Cathryn Frazier-Neely had the proper vocal suppleness and emotional depth for Fiordiligi, and Susan Zaboji was vocally pert and quite funny as Despina. Debra Nagelhout (Dorabella) had fine moments, but her voice needs a bit more polish. Brendan Cain (Guglielmo) was usually reliable if not dazzling.

Thomas Ludwig conducted. Conducted a piano? More than that; witness the smooth balance of the ensemble singing. Elizabeth Kirkpatrick Vrenios directed intelligently, but a games motif running through the evening seemed somewhat overdone. It worked well with a dart game in the first scene and a chess game during Despina's aria on feminine wiles, but it seemed rather overdone and distracting when it got into croquet and tic-tac-toe.