Shocked by Subwoofer thru Speaker Outlets of Main Amp

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I have a JBL PSW1000 powered subwoofer. I just finished wiring a whole house audio system and when I hooked up the subwoofer using coaxial cables with rca hook ups on the end into my Denon AVR-887, amp, my home theater speaker connectors became line voltage. I've pulled the back off the sub woofer and nothing seems amiss, like a paper clip or something bridging a connection. No evidence of any problem. Any ideas?
 
I had the same kind of problem. I ran speaker wires up the front wall, across the room to the back through a suspended ceiling, and down the rear wall to my rear speakers. I got a jolt from the wires when I attempted to hook up the rear speakers. Using a multimeter the wires showed 32 volts. And the amp wasn't turned on. It turned out to be an induction problem from the wires running beside a couple of overhead florecent light fixtures. Rerouting the wires away from the fixtures fixed the problem. Before you hook your sub up, test the wire with a multimeter and see if there's any voltage. If so, then you have an induction problem. If any other speaker wire is running through walls, test them too. Hopefully its your sub amp causing the problem and not the wiring. Keep us posted on what you find.
 
I checked the rca outlets to the sub (at the wall) and no voltage. When I cut on the sub (without the rca wires plugged in), there is 110volts at either of the rca inputs at the back of the amp. So it's seems to be entirely within the amp, not the whole house wiring.

Any ideas?
 
lews said:
I checked the rca outlets to the sub (at the wall) and no voltage. When I cut on the sub (without the rca wires plugged in), there is 110volts at either of the rca inputs at the back of the amp. So it's seems to be entirely within the amp, not the whole house wiring.

Any ideas?

So the bit about the wiring you did is not related to any of this then. Basically you plug the sub in with no other cables connected to it, then you find 110V at it's input connectors? How are you measuring this voltage, i.e. probes from outer to inner?
 
Yes that's right. It's nothing to do with the whole house wiring apparently. Just the Sub.

It's interesting on the testing. I get a line voltage reading on both inputs, and on the outside and the inside (sliding the probe in like the male of an rca would go). It seems the whole thing is hot. Oddly, the subwoofer seems to work fine.
 
I'll need to check the two squares at home tonight. You are clearly way out of my league on knowledge.

It's just a 2-wire power line going into the unit, so I assume that there isn't any grounding wire (I guess just a neutral and a hot). You know I still find it wierd that the GFI doesn't trip.
 
Well that's what seemed wierd. I traced the power wire (ie, wire that plugs into the wall) and the one with the bigger squared spade traces to the transformer. I'm with you; I thought the squared spade of the plug was for the neutral and why would the neutral be powering the transformer. The other possibility is that the wiring in my house (a new house) is wrong.

I bought this thing used it could have been tampered with. But it seemed to work fine at my old house - who knows, though, maybe I just didn't notice it was running line voltage through the inputs.

Maybe the thing to try is to grind the squared spade so I can reverse the plug into the wall. What do you think?
 
Since the sub worked in your old house and not in the new one, there is a possibility that the receptacle wiring may be wrong. Easiest way to tell is get a receptacle tester.
http://toolprice.net/product/7290A?META=nextag-7290A
""The neon indicators give positive indication of circuit status. The unit simply plugs into any standard 3-wire/grounded receptacle (110-125 VAC circuits). Tests for six circuit conditions: open ground, open neutral, open hot, hot/ground reverse, hot/neutral reverse, and correct wiring. Succession of yellow and red lights provide indication of circuit status or specify which wire is defective."" I have one of these and would never be without it. If the receptacle tests fine then the problem is in the amp as was suggested in the "Solid State" forum.
 
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