A smart cookie, that Ben Heppner:  try out one of the most difficult roles in the heldentenor repertoire in a Wagnerian backwater.

Heppner trying on Siegfried in Aix-en-Provence

His performance at Saturday night’s premiere was in some respects a triumph and in others a work in progress.

For sheer visceral excitement, nothing beats the sound of Heppner’s lean, muscular high notes cutting through the orchestra at full volume _ and this orchestra was the Berlin Philharmonic, one of the finest in the world. The freshness and vigor of his declaration of love to Bruennhilde near the end of Act 3, “Sei mein, sei mein, sei mein!” (”Be mine!”) resonated through the Grand Theatre de Provence with thrilling clarity and punch.

That this came at the end of a long night _ three acts, each lasting more than an hour, with his character rarely off stage _ made it even more remarkable.

Heppner showed his newness to the part a few times: too much eye contact with the conductor early on, one or two missed entrances, a bit of holding back in the sword-forging scene. In Act 3 there were a few rough patches in the middle register when he had to sing softly, the only hint of vocal fatigue.

It’s ironic that Wagner wrote the role of his young superhero with such strenuous vocal demands that it can be sung only by a tenor whose voice has fully matured, typically in early middle age. Heppner, a 52-year-old Canadian with a bulky physique, is not going to make anyone think he’s a teenager, but he runs about the stage energetically and assumes a wide-eyed innocence that helps make him believable.