I have a few questions regarding a scultpure I am making- To keep it simple, let's say the sculpture is simply a rectangle, ~4'x8'. What I would like to do is set up eight motion sensors (one in each corner and one in the middle of each side) that when triggered activate a corresponding tape player with a tape loop inside to play on a central speaker unit. So the goal is simplest terms is for people to walk around the installation triggering a musical note and with enough people organize a composition or a chord. Each motion sensor would have its own respective tape player, but I don't have the funds to supply eight seperate speakers. I also don't have much money to spend on PIRs, however, ebay has a bunch of PIR home security sensors for around $5. This project is most likely going to be crude, so I'm not overly worried about how sloppy it may turn out. What I imagine is to have the tape players always on, always running their loops, and a way for their respective sensors to allow the sound to play through the speaker. The gaps I need filled- 1) Is it sensible to use the PIR sensors I'm finding on ebay? (Aleph XP-40, Ademco 998) 2)short of buying eight speakers, is there a way to hook up all eight tape players to a central speaker unit? 3) If I am making this overly complicated, might you know of a better way to accomplish the task?