The Third Houston Early Music Festival will take place Feb. 12-15 at venues across the city. Cosponsored by Ars Lyrica Houston, Bach Society Houston, Mercury – The Orchestra Redefined, and the Piping Rock Singers, the festival will feature five main-stage performances. In addition, an inaugural Young Artist Showcase program will highlight period-instrument student ensembles from Texas universities and colleges. "Early music" is from the mid-18th century and before — the Baroque, Renaissance and Middle Ages — and ranges from Gregorian chants and Bach organ works to Handel operas and Vivaldi concertos. For performance and ticket information, see www.houstonearlymusicfestival.org.