This delightful album is a fascinating development of the musical ares opened up by Jan Garbarek's Officium, which featured the latter's improvised responses to medieval church music sung bt the Hilliard Ensemble. Extempore is a more adventurous collaboration between Houseplants, a quartet of sophisticated jazz musicians from the dynamic new generation which emerged in the Eighties, and Orlando, an award-winning early music vocal quartet. The two groups interact more freely and with greater variety than Garbarek and the Hilliards, but without losing the haunting resonances of plainchant or other medieval church music. Improvisation was common in medieval music, and here the Houseplants improvise with real focus. They have encouraged the Orlandos to improvise pieces, using a line of text as inspiration. Five of the eighteen pieces were created without involving the jazz musicians. But the latter have two tracks all to themselves, Hearing is Believing, with Lockheart's tenor saxaphone and Warren's piano in a rubato, ecstatic development of a plainchant fragment which conjures up the churchy gospel warmth of Keith Jarrett and Garbarek. Their other piece, Single Tear, begins with a mistily tender piano introduction, and then the ballad melody is rendered plainchant-wise by tenor saxophone, piano and bass in unison, followed by exquisite short solos from Lockheart and Philips. Brevity and sonority are the hallmarks of this music. Despite the centuries seperating the two musics, they seem to meet and breathe together without any sense of strain.Harmonium begins with solo tenor voice and humming accompaniment. The countertenor takes over, then hands it back to the tenor, where the piano introduces an ostinato over which the voices sing in harmony. The double bass and percussion join in and the soprano sax adds lyrical comments, dialouging with the voices. The variety of approach in all their joint pieces is remarkable and utterly absorbing. BBC Music Magazine, May 1998.