Hector Berlioz’s six songs (1840-41) setting the poetry of his friend Théophile Gautier were published together merely for the sake of convenience under the title Les nuits d’été. It’s not clear for whom he composed them; the score is labelled ‘for tenor or mezzo voice and piano’, although he may have been inspired by the mezzo Marie Recio, with whom he had embarked upon an affair (she later became his second wife). In 1843 he orchestrated the fourth song, ‘Absence’, for her, but the other five weren’t orchestrated until 1856. Each was dedicated to a different singer, the voice types ranging from mezzo to contralto, tenor and baritone, forcing Berlioz to change some of the keys.

Voice descriptors mean little to Michael Spyres, who sings Les nuits d’été here in the ‘original keys’ – ie the keys of Berlioz’s orchestrations. Four of them sit within his most familiar tenor range but he sings ‘Le spectre de la rose’ (in B major) as a baritone, while ‘Sur les lagunes’ is in F major, taking him down into bass-baritone territory. That the American ‘baritenor’ could achieve such a thing in the studio comes as little surprise but Spyres recorded the songs in concert in Strasbourg’s Salle Érasme, effortlessly switching between voices. This is not, however, a display of vocal acrobatics – Spyres is too classy to make it all about himself. He is mellifluous in both registers and this is an excellent rendition.

It’s rare for male singers to record Les nuits d’été. The most recent example I heard was the stylish Stéphane Degout, and Spyres’s baritone can withstand the comparison. His deft phrasing and attention to text are outstanding. ‘Absence’ is beautifully affecting, while there’s a cheeky swagger in ‘L’île inconnue’.

If I have a beef about anything here, it’s the tempos of John Nelson, continuing his Berlioz series with the Orchestre Philharmonique de Strasbourg. ‘Villanelle’ is taken at a leisurely allegretto tempo (although not as slow as Berlioz’s metronome marking of crochet=96), while ‘Le spectre de la rose’ zips along almost too quickly – the phrase ‘j’arrive du paradis’ could do with a little more spaciousness. In contrast, Nelson slams on the brakes for a really slow ‘Sur les lagunes’ (7'03").

As on Degout’s album with Les Siècles and François-Xavier Roth, the coupling is Harold en Italie, that ‘non-concerto’ for viola. The soloist here is Timothy Ridout, whose warm, silky chestnut tone is beautifully polished. He is recorded quite closely so we hear the glassy sul ponticellos in detail, as well as his smooth singing tone in the Abruzzi mountains. In the finale, where Berlioz ignores his soloist for 55 pages, Ridout literally leaves the stage during the brigands’ orgy, reappearing among the audience in the final minutes (you can still watch the concert stream on Medici) for his last soliloquy (10'15").

Nelson is generally more relaxed than Roth, although his pilgrims march along at a tempo indicating they’re seeking a pizzeria with a good deal of urgency. His shepherds pipe exuberantly in the third-movement saltarello, with characterful cor anglais solos; indeed, the Strasbourg woodwinds are a delight throughout. Not quite a Harold to displace Zimmermann and Roth, but Spyres’s Nuits d’été is most persuasive.