The Metropolitan Opera's "Lucia di Lammermoor," which was performed Saturday afternoon and will be repeated Wednesday evening at the Kennedy Center Opera House, offers an array of generally good voices desperately in search of direction.

It is one of the oldest productions currently active in the Metropolitan repertoire, having originated in 1964 as a vehicle for Joan Sutherland, and it shows its age--not in the sets and costumes, which are still quite effective, but in a musical and theatrical formlessness that leaves it enjoyable primarily as a collection of good melodies well sung.

New stage direction was reportedly introduced into the production last year, but on the evidence of Saturday's performance, the singers must have been directed simply to stand up and sing. The prevailing immobility of the chorus was particularly notable so soon after its vivid visual impact in "Boris Godunov."

Conductor Michelangelo Veltri accompanied the singers conscientiously, but there were frequent recurrences of a problem also heard in his "Adriana Lecouvreur" a few days earlier. Particularly at the beginning of an act or scene, the orchestral sound would submerge the voices--even, for a moment or two, the mighty Met chorus. When they could be heard, the voices were of Metropolitan quality, notably Ashley Putnam in the title role and Pablo Elvira as Ernesto.

Tenor Neil Schicoff sang with the same limitations of dynamic range and nuance, the same lack of subtlety in phrasing that were heard in his "Adriana," and his acting was a shade below the standards of this production, which are not very high. In the big confrontation scene of Act II, for example, when he is facing alone a dozen adversaries with drawn swords, he turns his back to them to sing directly at the audience (or perhaps to keep his eye on the prompter). Still, he has a decent voice and the audience clearly liked him; at a time of acute tenor shortage, perhaps we have to make allowances.

The famous sextet, which is half the reason people buy tickets for this opera, seemed well sung but not well coordinated: six voices in search of an ensemble sound. Putnam's mad scene (the other half of the motivation for ticket sales) went much better, as did the solo numbers generally. Rumors that Putnam has been having trouble in her upper register were not at all confirmed in Saturday's performance.