The men's choir Clerestory, originally a splinter group from Chanticleer, is one of the less-known Bay Area treasures. SFCV has been following it for a few years and the reviews have been uniformly excellent. If you've never looked in on them, here is a wonderful-sounding program about the music of Notre Dame Cathedral, Paris, presented in conjunction with Humanities West's seminar weekend, “The Soul of Medieval Paris.” It begins with the 12th-century magic of Perotin, high medieval culture in full flower, and continues through to the 20th century and works by Francis Poulenc and Arvo Pärt.