I was just hired in a school where there is a built in stereo system through the roof. I believe I've found the connection, which is just two cords that are labled "R" and "L" and that have red an black cords with stripped wires at the edge. I tried putting these wires into an output line with a Dayton Audio power amplifier and I tried putting an input into this and I haven't gotten any sound even with turning the level up (Cautiously mind you). before investigating any further and breaking the entire system completely I'd like input into the matter. I have another stereo that has the ability to put the right and left speakers straight into that but I'm not sure if I should use that or put it into the amplifier. Until I nkow, I'm going to leave the system alone.