Thursday evening's Assembly Hall audience was treated to a special event when the American West Symphony and Chorus, under the direction of Joel Rosenberg, presented the concert version of George Gershwin's stage masterpiece, "Porgy and Bess."

Adding to the musical splendor of the evening were the four soloists in the major roles: sopranos Cora Johnson Lockheart and Margo Watson, tenor James W. Miller and bass Barry Bounous. This was an evening that featured superb performances by the chorus, the orchestra and especially the soloists. All of these fine musicians brought out the spirit and essence of Gershwin's music in a performance worthy to be recorded.Rosenberg, too, did a tremendous job. He had outstanding control of his forces and he provided the singers with a finely tuned accompaniment, even though in a few places the orchestra drowned out the soloists.

Rosenberg's tempos tended to be on the slow side, although this very definitely worked to the music's advantage. These languid tempos added to the overall effectiveness of this performance.

One sensed that this was going to be a memorable evening early in the first act when Lockheart sang one of the opera's greatest numbers, "Summertime." The slow, almost drawling, tempo together with Lockheart's strong and emotionally charged interpretation made this song come alive. One could almost feel the humidity of a Southern summer in this performance.

Lockheart has a strong, rich, expressive voice. She was a wonderful addition to the evening's cast.

Watson's voice, too, is expressive and powerful, and she sings with a tremendous amount of feeling. She sounded great in duets with Bounous, who also was outstanding. Especially exciting was their rendition of "Bess, You Is My Woman Now." This was a lush, supple performance of one of Gershwin's loveliest ballads. Also noteworthy was the duet "Oh, What You Want Wid Bess?" Watson and Bounous make a great vocal team.

Miller was the evening's standout performer. He only had two solo numbers, but he put his soul into them and turned them into show-stoppers. He did a loose-limbed, bluesy rendition of "It Ain't Necessarily So" and a persuasive performance of "There's a Boat Dat's Leavin' Soon for New York". He was just great.

Of the choral numbers "Oh, I Can't Sit Down" and "I Ain't Got No Shame" were swinging, rhythmically charged knockouts.

This was a performance of a caliber that made this evening unforgettable. Fortunately, the performance repeats on Friday. This is a concert that ought not to be missed.