As long as there have been maestros who love opera but are not willing to spend the time in an opera house rehearsing a new production, operas in concert have been a fact of musical life. Without concert operas, we would not today have the legendary Toscanini performances on RCA records of Puccini's ''La Boheme,'' or of the Verdi operas - ''Otello,'' ''Falstaff,'' ''La Traviata,'' ''Aida,'' ''Un ballo in maschera.''
Riccardo Muti performs fully staged operas only in Europe, where he gets all the rehearsal time he feels he needs. It has been said of the music director of the Philadelphia Orchestra that his musical profile cannot be fully appreciated unless he has been heard in live opera. Thus it was with intense interest that one approached his concert performance of Verdi's ''Macbeth'' with the Philadelphia last week in Carnegie Hall.
Muti has already recorded ''Macbeth'' in a performance marred by erratic, often arbitrary-sounding tempos, and a pervading lack of character and atmosphere that, unfortunately, marks just about every one of his opera recordings to date.
His performance in Carnegie, however, was more auspicious. It found the Philadelphia playing with passion, commitment, and a tremendous sense of atmosphere. The conductor reveled in the beautiful sounds it could make and exploited that sound, particularly in the quieter end of the dynamic scale.
To hear such a magnificent orchestra lavish this much skill and control on this score is to hear more clearly than ever Verdi's extraordinary orchestral sense. The conductor's balances may have been reticent with the brass, but the textural clarity was often startling. The attention to nuance, to the felicities of Verdi's orchestral sensibilities, were all remarkable.
Muti's performance indicated anew that his sense of Verdi is primarily as a master orchestrator who fitted voices into that fabric, rather than a man of voice who created sounds to support glorious singing. Muti is also somewhat remote emotionally: He is fine at getting across majesty, or nervous excitement, but scenes of tremendous passion or desolate suffering (as in the huge Scottish exiles' chorus) lack pathos.
At times, his tempos proved rather brisk - the finale of Act I positively scurried along without developing the haunting, aching sweep inherent in the music. Certain moments, such as Lady Macbeth's ''Brindisi,'' took on a demonic quality at the somewhat slower-than-usual tempo set. At times Muti was unexpectedly pliant with his singers: On records he usually confines them to a musical straitjacket. At other times, he still expected them to toe the metric line unrelentingly, rendering certain passages vocally awkward.
In Renato Bruson (Macbeth), Muti has his ideal singer. Mr. Bruson, like few others I have heard with Muti - either live or on records - can translate the conductor's insistence on strict adherence to Verdi's extreme dynamic markings and make them work interpretively. His performance throughout was a master's blending of superb singing and subtle artistry. Even so, some of those extremities sound mannered, even as executed by Bruson.
Elizabeth Connell, the Lady Macbeth, started her career as a mezzo, but has now pushed her voice up to a soprano. The ''new'' Connell has a secure, penetrating top, a lighter middle range, and occasionally low notes of tremendous potency. Overall, however, the vocal weight seemed unequal to the demands of this role. Interpretively, her attempts to highlight a curious innocence only infrequently cast this larger-than-life role in new light. Miss Connell as yet seems unable to consistently deploy the voice in all its potential from top to bottom.
Simon Estes sounded more like a baritone than a bass as Banquo. Luis Lima sang Macduff ardently. The Westminster Symphonic Chorus was totally committed, though a bit shallow of tonal quality. But the star of the evening, along with Bruson, was the Philadelphia Orchestra. A great orchestra, the Philadelphia gives a sound, a unity, and a technical polish that are frosting on the operatic cake.
'Forza' and 'Boheme'
At the Met, Verdi is being oddly served in its current revival of ''Forza del destino.'' James Levine, who revealed new depths in his reading of ''Macbeth'' here last season, finds the sweep and majesty of ''Forza,'' and communicates it through one of the finest opera orchestras extant. Renato Bruson is a superior presence on stage, but vocally he was overparted by the role of Don Carlo. Jose Carreras sang the role of Alvaro stressfully, although when the voice was not pushed, it still possessed the gleam and tonal beauty that have been the strengths of his singing. Nicolai Ghiaurov's Guardiano still invokes authority of presence and of the lower range of the vocal scale.
Grace Bumbry is not in truth capable of sustaining the grand Verdian line, and the upper register is exceedingly inconsistent, the occasional handsome pianissimo notwithstanding. She brings a star performer's allure to the role of Leonora without ever really offering the emotional side of her role.
The production, as staged by John Dexter, moves rather like a concert in stage dress - despite the handsome Eugene Berman sets and the awkward Peter Hall costumes - robbing audiences of the feeling of a production that fully captures the drama, mood, and action of the music.
For that sort of Met production one must turn to Puccini's ''La Boheme'' in the current Franco Zeffirelli staging. In this, its second revival, it still looks spectacular - a large staging for a large house.
Neil Shicoff is the superb Rodolfo, singing with verve and sensitivity and acting with unusual grace and naturalness. His Mimi, Catherine Malfitano, deputizing for an indisposed Mirella Freni, managed a vulnerable, vocally secure , histrionically beguiling performance as the simple seamstress.
Barbara Daniels made a rousing debut as Musetta - ebullient, sassy, vocally strong, visually winning - in a bold performance that held focus at all times. Brent Ellis (Marcello), James Morris (Colline), and Italo Tajo (Benoit and Alcindoro) were all familiar from past performances, and all outstanding. Eugene Kohn led a solid performance, alert to his singers' needs, if at times a bit on the leisurely side.