Three American singers — models of refinement and technique, to be sure — joined an Italian conductor in a program of arias and duets that never lacked for dramatic potency.

The real high point of the concert came in excerpts from Bellini’s I Capuleti e i Montecchi, an opera based on the same source material used by Shakespeare for his Romeo and Juliet, but with plot differences. Soprano Laura Claycomb, substituting on short notice for the originally scheduled Nicole Cabell, was radiant and spirited in Giulietta’s plaintive aria “O quante volte” (with horn and harp solos). She took her portrayal to another level in an incendiary interaction with DiDonato’s Romeo throughout the varied phases of a non-Shakespearean scene from the opera’s first act, “Ah! mia Giulietta!” But what opportunities for vocal acting it provides.

After dashing onstage in a trouser suit for this scene, DiDonato made every complex vocal hurdle into a tour de force, pushing the character’s frustration, ardor and persuasiveness to exhilarating extremes. Altogether, she displayed her accustomed precision and subtlety, along with a variety and power not always heard from this artist in fully staged opera performances. The impact seemed as stimulating to her partner onstage as to the audience. Claycomb’s soaring range, fine-spun pianissimos and minute vocal embroidery achieved a startling blend of technical poise and expressive power.

-David J. Baker