The remarkable range of American “baritenor” Michael Spyres’ voice—he can sing both baritone and tenor—is strikingly evident in his performance of Berlioz’s Les Nuits d’été, an orchestral song cycle for which Berlioz anticipated that a mix of different singers would be needed. Spyres sings all six songs in their original keys himself, scaling the heights in his sweet-toned take on the opening “Villanelle,” while digging deep for the melancholic “Sur les lagunes.” Spyres’ responsiveness to text and atmosphere produces highly impressive performances. The coupling is substantial: Berlioz’s symphonic viola showcase Harold en Italie, with the outstanding Timothy Ridout as soloist. The Orchestre Philharmonique de Strasbourg paint Berlioz’s Byronic pictures vividly, under conductor John Nelson.