Conductors say they like to present operas in concert form because the format allows audiences to focus on the music and visualise dramatic events in the imagination. (Rarely do they come out and say that it does away with the producer.) In a programme note, James Levine touched on another reason apropos of Berlioz’s sprawling Les Troyens: that it is “based in a series of tableaux rather than real action”. This operatic treatment of Books 1, 2 and 4 of Virgil’s Aeneid is no longer than a long Wagner opera, but in the theatre it can seem longer. Sample the score or a recording at home, on the other hand, and any given number can seem a masterpiece.

The Boston Symphony’s recent concert performances observed Berlioz’s division of the opera into two parts (a strategy by the composer to get the work on stage) and presented each part on separate evenings. But on Sunday it gave them both, with a dinner interval. Freed of the need to demonstrate theatrical vigour, yet teeming with the exhilaration of a live performance, Les Troyens made a memorable impression. One could marvel at the music and pay special attention to the wealth of instrumental detail, such as the clarinet solo in the Andromache pantomime or the eerie instrumental combinations that accompany the appearance of ghosts.