Re: Complete the DC circuit?
I saw this static effect personally at a church a few years ago while troubleshooting their podium mic. Their sound tech complained there was a "short" in the gooseneck of the mic which would "pop" when anybody adjusted it. I watched it happen from back at the console, and was a little puzzled why it only seemed to "pop" one time, then would be pop free for a while. When I walked up and adjusted the mic myself I got a serious static shock which then made the big "pop" in the sound system. Looking down I noticed the carpet and asked them how long the mic had been misbehaving, which we found coincided with the new cleaning guy who was steam cleaning the carpets, but not spraying any anti-static compound after cleaning. Yikes!!!! 8O~8-O~:shock:
When troubleshooting wacky happenings in sound systems (or anything else), it's always best to try to experience the event yourself. That is, I try to observe the failure while watching everything else in the room. Once you see a correlation, it's pretty easy to determine cause and effect. So if the shock only occurs with the phantom power on, but not when off, then it's time to meter from the earth to the body of the offending mic. Understanding grounding is also a good thing for sound system troubleshooting since ground plane differential voltages are what causes electric shocks to humans. For those of you not familiar with using meters to measure voltage and and concepts of shocks on stage, here's a pretty good primer I wrote on the subject: Stage Electrical Safety
