Magdalena Kozená Queen's Hall, Edinburgh

Where were Magdalena Kozená's trademark killer heels? And where were the usual formalities of a morning concert in the International Festival? Members of the consort of instruments, Private Musicke, made their way casually on to the platform, already strumming, plucking and tapping, joined almost surreptitiously by Kozená. Wearing a summery long dress, her hair tousled, she had stepped off the pedestal of high-heeled shoes and opted for bare feet. Looking unusually relaxed, she launched into a delightful programme of music from the Italian and Spanish Baroque, based around her forthcoming disc with the ensemble, Lettere Amorose.

The music, punctuated by the odd instrumental piece, featured madrigals and more substantial melodic pieces by Monteverdi and Caccini. Less familiar names included Vitali, D'India and Kapsberger. Responding to the varying mood of each song, Kozena was movingly expressive in Merula's "Canzonetta Spirituale", in which the Virgin Mary sings a poignant lullaby to her son while anticipating his death, and no less intense in D'India's dramatic lament to a dead lover. She clearly relished the alternating rhapsodic and declamatory twists and turns in "L'Eraclito Amoroso", which the renowned feminist singer-composer Barbara Strozzi created as a vehicle for her own virtuosity. Kozena interpreted this scena compellingly, with a strident theatricality.

In refreshing contrast to some other period-instrument groups, Private Musicke – made up of viols, plucked instruments and percussion – displayed a less obsessive concern with uptight clarity and nail-biting intonation in favour of an infectiously enjoyable, almost improvisatory reflection of the texts and music. Led by guitarist Pierre Pitzl, the band never glossed over the unexpected details in the accompaniments, the inventiveness of tiny threads of tune. In musical dialogue with Kozena, the effect was of an intimate, equal and happy partnership.