Scottish Chamber Orchestra, Usher Hall, Edinburgh, review Opera always strains our credulity, but few strain it quite as severely as Mozart's Così fan tutte. Two soldiers bid a tearful but entirely fake farewell to their lady loves, disappear for the space of an aria, and reappear disguised as Albanians to test their ladies" fidelity. In a production, there's the fun of seeing just how bad the disguises are. In a concert performance, such as this one from the Scottish Chamber Orchestra, the absurdity becomes absolute. The two ardent swains here were as conveniently contrasted as you could wish: Maximilian Schmitt short and fair as Ferrando, and plaintively soft in tone, Adam Plachetka as Guglielmo tall and dark and masterful in both vocal timbre and demeanour. Even the dimmest girl would have had trouble mixing them up. Off they went in suit and tie, back they came a few minutes later looking exactly the same. In a strange way, this purified the piece. Instead of being a wry comment on human beings" willingness to be duped, the girls seemed to be in the grip of a total hallucination. This meant the opera's comic edge was much reduced - I've never witnessed a performance of Così with so few laughs. Romanian soprano Laura Tatulescu worked overtime at being the pert maid Despina, all hands on hips and wagging index finger, mugging like a music-hall comedian as the Doctor who revives the Albanians. But it felt somewhat overdone. Christopher Maltman as the aged Don who sets up this trick to test the girls seemed to be mildly amused by its success, but he lacked the edge of sadism and cynicism the role needs. But if the comic and erotic elements of the opera were thinned out, what you might call its spiritual aspects were correspondingly ennobled. They're focused on Fiordiligi, the girl who holds out the longest against the Albanians" entreaties, and Sally Matthews, dressed in virginal white, caught her essence. The moment when she realises she's going to fail is a moment of real anguish, and both she and the orchestra made sure we felt it. Strong though the cast and chorus were, the real heart of the performance lay in the sublime playing from the orchestra under conductor Robin Ticciati. In Fiordiligi's great aria of repentance Per pietà it was the shapely and tender playing of the woodwinds that gave the music that extra edge of poignancy.