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<blockquote data-quote="Mike Sokol" data-source="post: 64743" data-attributes="member: 1989">Re: Complete the DC circuit?I&#039;ve actually found one of my &quot;bad&quot; XLR cables that was mis-wired with the twisted pair on pins 1 and 2, and the shield on pin 3. When you turn on the phantom power, the shield is energized at 48 volts DC with respect to the mixer chassis ground. And, of course, anything grounded on stage such as a guitar amp will provide a shock path to a musician. This will hum a lot if the cable is long, or course. But a cable mis-wired like this won&#039;t show up even on a standard cable tester. I&#039;ll bet if he took a volt-meter and probed between the chassis ground of the mixer and the body of a mic, it would read 48 volts DC as he switched the phantom power on. A mis-wired cable is the only explanation I can think of. And yes, DC voltage is much less dangerous to a human compared to AC voltage at 60 Hz. Yes, Edison was actually right about Westinghouse&#039;s AC power being a killer, and his DC power was actually much safer. Of course, AC power won out and the rest is history. Mike Sokol</blockquote>

[QUOTE="Mike Sokol, post: 64743, member: 1989"] Re: Complete the DC circuit? I've actually found one of my "bad" XLR cables that was mis-wired with the twisted pair on pins 1 and 2, and the shield on pin 3. When you turn on the phantom power, the shield is energized at 48 volts DC with respect to the mixer chassis ground. And, of course, anything grounded on stage such as a guitar amp will provide a shock path to a musician. This will hum a lot if the cable is long, or course. But a cable mis-wired like this won't show up even on a standard cable tester. I'll bet if he took a volt-meter and probed between the chassis ground of the mixer and the body of a mic, it would read 48 volts DC as he switched the phantom power on. A mis-wired cable is the only explanation I can think of. And yes, DC voltage is much less dangerous to a human compared to AC voltage at 60 Hz. Yes, Edison was actually right about Westinghouse's AC power being a killer, and his DC power was actually much safer. Of course, AC power won out and the rest is history. Mike Sokol [/QUOTE]

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