The Old Vienna Kaffeehaus is a revival concert scheduled for Saturday, Aug. 17, from 1-9 p.m. in Hopkinton. This is a pay-what-you-can, reservation-only, not-for-profit house concert, although it will be outdoors. The lineup includes Hopkinton folk singer Barbara Kessler and her daughter, national recording artist Emilia Ali. For more information, including a list of performers, and to RSVP, visit 0830club.com/ovk. Location will be provided after registration.