Originally Posted by
Eric DeSilva
The OP indicated that he changed cabling to the receiver, not the cabling from the receiver to the speakers, and that the system (presumably including the speakers) was in use before. Under those circumstances, I would assume that the speakers aren't the problem, since they would have caused problems before as well... So I'm with Myk on this one.
The sub is likely a powered sub--if it is 100K ohms, it is showing an impedance that would correlate to a line level input; that conclusion is also consistent with a potentiometer (not a rheostat in all likelihood) to control volume and a separate power supply. But, if the sub has both speaker inputs and line level inputs, you won't blow things up by using the speaker level inputs--that is what they are designed for.
If my assumption that nothing from the receiver to the speakers changed is wrong, however, I'd double check all the connections to make sure a bare wire isn't touching both (+) and (-) terminals on the speaker, or that there isn't a short in the speaker wire (although that seems unlikely) or speaker. If disconnecting the speakers "solves" the problem, that would tend to indicate a short on the speaker end. Try disconnecting them one by one to see which speaker is at fault. If it is attributable to one speaker, get a multimeter and check the resistance across the two connections on that speaker's wire that would connect to the receiver. That should register about 8 ohms. If it is zero, disconnect the speaker wire from the speaker too, and check the resistance across the two speaker terminals. Again, it should be about 8 ohms. If it is zero, something is shorted inside the speaker. If not, you might want to check the cable itself, there may be a short somewhere inside the cable jacket.