This is not at all meant to damn this performance with faint praise. It would be folly to take the excellence of AVA singers for granted. Rigoletto is one of the most richly drawn baritone roles in the repertoire, and Octavio Moreno, who opened his freshman season at AVA with a marvelously slimy Don Giovanni, similarly evoked equal measures of pity and disgust with this characterization. In the Mozart, Moreno was able to balance the menace with comedy, but there is no such foil in this role, and he did not quite fully occupy the inky darkness of the character.

Stephen Costello, as the Duke, displayed a liquid tonality, superb legato and dynamic control in his singing, and he tread the boards with a graceful fluidity that stood apart from the cast. This theatrical ease, combined with a beautiful voice, self-effacing charm and boyish good looks marks Costello as a tenor of exceptional promise, if ever there was one.

Costello, who is now in his third year at AVA, gains in control with each performance, and produced thrillingly nailed high notes. There were occasional missed pitches from him Sunday night, but nothing so spectacular as Ariya Sawadivong's mishap in Gilda's big first-act aria. Sawadivong, who possesses a sprightly and charming soprano, somehow floated into a different key signature, presenting one of those dangerously thrilling moments that only live opera can deliver. It all ended well, mainly due to music director Christofer Macatsoris' authoritarian composure, as the errant tonality unintentionally added a Straussian tension.

That sort of firm, guiding hand is to be expected from Macatsoris. Although he never has a singing role, his is the true voice of AVA. This evening, as if it were possible, he produced a sound as vibrant, dramatically alert and sensual as ever. Great singers come and go at AVA, but this pillar remains. We are lucky.

Rigoletto

Through May 20, Academy of Vocal Arts, 215-735-1685, www.avaopera.com