I've posted on here a few times concerning the electrical problems I continue to encounter for my video installations. And yet, here's another one. If anyone remembers, I posted a month back or so concerning the use of an audio signal from a home audio receiver to open and close a small electromagnetic valve. I tried a few methods and was unsuccessful, but after blowing the fuse in my multimeter I'm back at it again. I threw the receiver on Phono, and started up my LP of Led Zeppelin I. Metering the the speaker wire on the ACV setting, I believe Robert Plant managed to get around 30 volts before my mom demanded to know "Just what I thought I was doing". The receiver I'm using still had about 10 percent more until maximum volume, so I'm pretty confident I could get around 40 volts. I think it was the loudest I've had my speakers, and boy did it sound good. So, my question is this: Can 30 AC volts provide enough power for an electromagnet? From what I've read up on, it's largely dependent upon how many/how tightly wrapped the coils are. Store-bought electromagnets like this one are often powered by 6 DCV, is that something that can be powered with AC as well? http://scientificsonline.com/product.asp_Q_pn_E_3113200 If so, then would I just connect the speaker wire directly to the electromagnet? Or will I need to get an AC to DC converter? I realize that these are probably all basic electrical knowledge questions, and really appreciate anyone who helps me out. If I need to clarify any part of the setup or a diagram would help, please let me know.