A matched set of empty rooms sit across from each other at the Henry, each with its own muted soundtrack. A speaker looks at you from each corner, while blond benches conceal the sound equipment. Four spotlights are directed at the benches, casting butter-pale walls into shadow. The rooms look identical. Only they don’t feel that way. This is +Room-Room, a two-part, two-artist sound installation composed using the gallery’s ambient noises. Both Seattle-based Yann Novak and Vancouver, B.C.–based Jamie Drouin began with the same aural details: whooshing, white-noise air conditioning, and a low mechanical drone. In creating +Room, Novak added to the room’s own noise, while Drouin took those sounds apart. Somehow -Room is, in fact, a more ominous place to be. +Room seems to ring with occasional church bells, punctuated by a fan’s live metallic percussion. -Room becomes a claustrophobic enclave of unspooling low drones, wave upon wave of murmuring tones. After you’re compelled to leave that space, you’ll notice that +Room wears its yellow walls at a somehow brighter hue.