Can something be unprecedented without being radical? Even in a town that, musically speaking, has seen a bit of everything?

Such was the weekend's "Myths and Magic" program by the Philadelphia Singers that featured two genre-fusing works from different eras that seemed to belong together - and perhaps no place else. Gian Carlo Menotti's all-but-forgotten neo-madrigal work The Unicorn, the Gorgon, and the Manticore stood well alongside the Jake Heggie/Gene Scheer choral opera The Radio Hour (heard here in its East Coast premiere), with both pieces achieving distinctive personalities via carefully selected elements from the past plus a modern conversational tone and an urgency of purpose.

Menotti's story of a strange old man who has a pet unicorn (among other things) unfolds in a series of madrigal-like movements that could be self-consciously quaint without its serious undercurrents: Written in 1956, the piece is clearly a coded protest against the ultraconformist McCarthy era (the old man, we're emphatically told, was not a churchgoer) when the composer was living openly as a gay man.

The piece doesn't entirely ring true to 21st-century ears: Instrumental interludes feel borrowed from Ravel, and the story itself seems enamored with its own exoticism. But its long stretches of unaccompanied vocal writing are the sort of thing that only a professional choir such as the Philadelphia Singers could manage with little audible strain.

The Radio Hour has many more moving parts in its free-floating narrative about a woman fighting her way back from a near-suicidal depression, with semi-staged presentation by choreographer/director Sean Curran. Sets included a large radio console, a table, and a Jean Cocteau-esque doorway that was, figuratively speaking, the rabbit hole into her consciousness.

The central role of Nora is usually played by a non-speaking actress, but here it was danced by Elizabeth Coker and one now can't imagine it being done any other way. The part of the chorus representing her thoughts was positioned in the upper gallery overlooking the stage in the Temple Performing Arts Center, while the other part representing what her radio was saying was off to the side.

The music practices tough love toward its protagonist: We're never asked to feel pity toward her in Heggie's sassy melange of 1940s pop-music styles (he's a brilliant musical mimic) with an instrumental ensemble that includes some fairly jazzy sax writing. Nearly every element of the piece makes you glad it exists, from the way it stretches choral forces to its ultimate message about why life is worth living.

Discussion of Scheer's libretto has to wait for a better-enunciated performance. Though the hallmark of the Philadelphia Singers has long been its robust, adult sound, details, at least on Friday, were partly cloudy.