John Cage’s voice-stretching Song Books (1970) are much closer to a theatrical “happening” than a traditional song cycle—depending on how you interpret his sometimes straightforward, sometimes gnomic performance instructions for texts by Thoreau, Duchamp, Merce Cunningham, and other apostles of the avant-garde. Bringing them to the Henry in Voicing Cage is soprano Stacey Mastrian and co-performer/sound engineer Stephen F. Lilly, both members of Washington, D.C.’s Bay Players Experimental Music Collective. Mastrian’s fearlessly eclectic repertory includes Rigoletto and The Pirates of Penzance as well as Luigi Nono’s anti-fascist opera/manifesto Intolleranza 1960, and she relishes the scope Cage’s music offers. “Although there are definite parameters [in Cage’s scores], you never quite know how someone will interpret the specific things that are there,” she told me recently. “Most of my training has been [to] learn to do a piece a specific way, [to] get so you can produce it this way all the time. With Cage, I feel like there’s more opportunity for play … You just have to trust whatever is going to come out at the moment.” Plus there’s the pleasure of stepping off the Verdi/Puccini career treadmill: “[When] 50,000 people do the same opera aria, it’s nice to be able to offer something to people that can leave a lasting impression in a way that other pieces might not.” GAVIN BORCHERT

Fri., Nov. 30, 7 p.m., 2012