“The Encounter” is part Broadway show, part radio play. On stage, Simon McBurney tells the story of a photographer lost in the Amazon — he uses pitch-shifting microphones, looping pedals, and a binaural head to reproduce the sounds of his journey; and you in the audience listen in using a pair of headphones at your seat. The effect is powerful and transporting. “The muscle or the sense that we use to get to this place is not just your hearing, it’s not just your ears, it’s what lies between your ears,” McBurney tells Kurt Andersen. “It’s the power of your imagination.” McBurney brings some of his gear into the studio to show how it’s done.