Thétre Français de la Musique is based in Compiègne, where its home is the posh but tiny Thétre Impérial built by Napoleon III. Their aim is to examine "forgotten French repertory" as well as to "restore an authentic French style" in performance. Heaven help French opera, then, for this double bill - Poulenc's La Voix Humaine and Chabrier's Une Education Manquée - proves musically intransigent and dramatically barely adequate.

We should, of course, be grateful to them for allowing us to experience La Voix Humaine in the theatre: Poulenc's monologue, depicting a woman's final phone conversation with the man who is ditching her, is usually performed in concert. Pierre Jourdan's production stresses the work's links with absurdist theatre, with the woman becoming entangled in phone cabling as her desperation worsens. Anne-Sophie Schmidt sings with considerable histrionic force, though Pascal Verrot's conducting is episodic and shapeless.

Une Education Manquée, however, is messy. A ribald skit on the Catholic education system, it presents us with a young couple, Gontran and Hélène, who reach their wedding night only to realise they have no sexual knowledge whatsoever. Chabrier wrote the operetta in 1879 for an all-male audience and wanted Gontran to be played by a mezzo in drag, thus generating lesbian frissons as nature takes its course and the couple lose both ignorance and clothes. Here, however, we have an edition prepared in the 1920s by Darius Milhaud in which Gontran is recast as a tenor, though Hélène gets a new aria describing her erotic fantasies in veiled, almost Proustian language.

Operetta works best played straight. Jordan's production, drawing on images from silent-film comedy, is so camp it robs the piece of humour and eroticism. Franck Cassard and Céline Victores-Benavente are colourless as Gontran and Hélène, while Philippe Le Chevalier is dire as Gontran's interfering priest. An embarrassment.

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