Despite Boston's lack of adequate facilities for the presentation of grand opera, a recently-formed group of professional opera performers has inaugurated its second season with a production of Puccini's Tosca. Sarah Caldwell's troupe, which uses the slightly militaristic name of "Operation Opera," has moved from the small and incommodious Fine Arts Theatre to the large but equally incommodious Loew's State movie house, now the property of the Catholic Church and newly dubbed the Donnely Memorial.

Miss Caldwell so far has employed singers who, at their prime, may perform lead roles at New York City Center Opera Company for a few seasons, thence to tour Europe where companies abound and decent voices are harder to come by. Though these artists do not produce an impressive performance, they generally prepare a role with dedication and sing it with dependable effectiveness.

Each of last season's presentation's (La Boheme, Barber of Seville, and Gay's The Beggar's Opera) pointed out that Operation Opera most needs improvement in orchestral performance. The instrumentalists are almost entirely chosen from the ranks of the Boston Symphony but they play without adequate rehearsal and sound like members of the Boston University Orchestra (a compliment to neither organization). Miss Caldwell adds to the confusion by conducting incompetently.

A major asset of the company has been the scenic inventiveness of the gifted young American designers whom Miss Caldwell has commissioned. One of the handsomest operatic settings I have ever seen was the elegant interior of Bartolo's house that Robert O'Hearn conceived for last spring's Barber. Robert Fletcher's decor for the new Tosca continues this very commendable tradition.

Last Monday's opening of Tosca fitted all too well into this pattern of steady, but Grade B, musical performances. Yet, it was not a bad job nor a purely indifferent offering. The main problem was one of casting. Tosca and Cavaradossi must be sophisticates; they are people of passionate conviction, important in the world of fashion and art. As portrayed by Lois Marshall and Thomas Hayward, the lovers seemed like the uncertain adolescents of Blue Denim. They sang well, though the round, supple tone of Miss Marshall is well known and pleasing, as is the light, lyric vocalism of Mr. Hayward. The orchestra stumbled through the score.

Still, if the casting of the two main roles was far from perfect and the performance in the pit highly unsatisfactory, the general effect did not lack tension and emotional impact. Credit this to the generally competent singing in both major and minor roles (in fact, the shepherdess, Taeko Fujii, was perhaps the most impressive vocalist of all), a well-prepared chorus, and Miss Caldwell's inventive and skillful staging of the main scenes.

The repertory of the Opera Group has so far been conservative. Of the pieces produced, only the Gay work could be called a novelty but its lukewarm popular reception intimates that such experimentation will be curtailed. This is unfortunate because smaller operatic groups ought to be daring where the large-scale expensive enterprises that the Metropolitan must attempt prove impossible. The second work this season will be Offenbach's well-tried operetta Voyage to the Moon, which was prepared by Miss Caldwell for the Boston Arts Festival in the summer of 1956. One can only hope that the spring offering, yet to be announced, will fulfill this group's responsibility to imaginative repertory. After all, they have a purely subscription audience and a guaranteed budget.

If Boston doesn't have an opera house, at least it once again has a resident opera company of some merit. With an expanded season and improved musical performances, Operation Opera may become a significant new addition to the sparsely covered American operatic map.