The conductor for "Carmen" must be formidable enough in the pit to integrate, enliven and polish Bizet's web of matchless arias, multiple choral tableaux, brilliant ensembles and glowing orchestral sound. The Washington Opera has the right conductor in Rafael Fruhbeck de Burgos.

And while the singing is not always up to Fruhbeck's high standards, it is sometimes quite good.

This is the American operatic debut of the National Symphony's principal guest conductor. But he took control in the first three minutes of last Saturday night's season-opening performance.

Starting the prelude, Fruhbeck dashed into the famous, convulsive bull ring theme with great thrust, but also with crispness and clarity. Next the toreador song sounded out perfectly poised in the strings, unforced and beautifully shaped. Then Fruhbeck came to the "fate" motif, which he hit with such galvanizing intensity that at the end the audience interrupted with considerable applause, despite the inconclusive diminished seventh chord and the tiny pause that Fruhbeck allowed before going forward. You would have thought Carmen already was knifed before the curtain could rise.

Because Fruhbeck has been here with the National Symphony for a month and a half, he has had a rare opportunity to work out the most precise details of the opera's phrasing and timbre, particularly with the orchestra and the chorus. The children's chorus, especially, was wonderful. Fruhbeck's "Carmen" recording is widely renowned, but his work here was even better.

Martha Senn, in the title role, had to fill in for another singer on very short notice. In the first act her nervousness showed: Carmen has to launch into the "Haba/nera" just a minute or two after her first entrance, and Senn did not have it in hand either musically or dramatically.

Fruhbeck directed the haba/nera theme with rhythmic pointing and passionate understatement. But Senn was barely approximating Fruhbeck's niceties. She also overacted -- hardly unprecedented among Carmens on first appearance. Her frenzy was a little too animalistic. The character of Carmen is really a study of contrasts, and early on Senn was missing some of them. Carmen's schizoid compulsion to flash unpredictably from passion to pensiveness and back is the bane of all who cross her path, as well as her destruction and Don Jos,e's.

But by the Card Song in act three, where Carmen literally deals her fate in the smugglers' mountain hideaway, Senn's characterization was more tightly focused and her phrasing more sophisticated. During the fatal last act, her performance was quite strong. When she recognized the disguised Don Jos,e from the balcony of the Seville bull ring she seemed genuinely startled. She fearlessly confronted her lover-cum-murder, and the defiant climactic line had real force. There is every reason to expect that Senn's Carmen will continue to develop.

Elizabeth Knighton as the gentle Micaela, the only halfway sensible person among the principal characters, sang with lovely sound; she was dramatically earnest though musically just a bit bland.

Both of the principal males were problematic. Dennis Bailey, as Don Jos,e, made some beautiful, if not particularly heroic sounds, especially in the Flower Song -- which is better than the mighty blasts that some tenors give it. He has a smooth, soft tenor, but he loses that quality as he gets louder. He lacked presence, which raised a fundamental dramatic question: Why would the lusty Carmen bother with him at all?

J. Patrick Raftery is a justly popular baritone with the company, but his portrayal of the matador Escamillo was at best embryonic. He had little of the vocal and theatrical self-assurance essential to the role.

In the lesser part of Morales, though, Allan Glassman had that quality. In the opening scene, he responded to Fruhbeck's lead with matching style, and his acting was fine. He doubled later as the smuggler Dancairo, and was good if less distinctive.

All the second-level roles were done well.

Michael Kahn staged the numerous crowd scenes with clarity and excitement, especially the flood of alguazils, banderillos and picadors passing in review before the mobs in the last act. But at some points in the production, the leading characters got a little lost in the shuffle; more spotlighting might have helped.

John Conklin's sets, borrowed from the Houston Grand Opera, were too cavernous in the middle acts, but that is the price one pays for unit productions, because the outer acts demand all the space they can get.

Still, Fruhbeck has given us a memorable "Carmen." Executive director Martin Feinstein says that talks are under way for Fruhbeck's return -- an event to be eagerly anticipated. CARMEN -- at the Kennedy Center Opera House this Sunday and November 12 and 15.