PORTLAND —

Harold Stover, director of the 21-voice a cappella ensemble, has put together an exciting and innovative program in celebration of the group’s 20th anniversary season.

The choir’s namesake period will be represented by Gabrieli, Hassler, Esquivel, Aliseda, Orlando di Lasso, and Jacob Handl, with more recent compositions by Paul Halley, Healey Willan, and Harold Stover. Plainsong, a carol or two, and seasonal readings by the singers, round out the program.

Admission is $15 at the door. Discount tickets at $12 can be purchased through 5 p.m. Friday, Dec. 19, by cash or check only, at Starbird Music and Longfellow Books in Portland and The Book Review in Falmouth, or at www.RenaissanceVoices.org. Admission for students is $5 (at the door only) with a valid student ID. The audience is invited to a reception after the concerts.

The Church is at 143State Street between Congress and Spring. For further information, call 207-729-4958 or 207-272-2275.

This program will also be performed on Saturday, Dec. 13, at the Sanford-Springvale Historical Society. Call 207-342-2797 for details about the Sanford concert.