How do I know which speaker wire is + and -?? Anyway to test it?

[AUMM]

I'm installing some surround sound speakers, the unit has already been pre-wired behind the crown molding, there is no markings on the speaker wire designating + or -.... is there a way for me to check to make sure i'm connecting to the correct location on the reciever? Does it make a big difference?

 

[DaveSimmons]

The wire is the same for + and -, just make sure to connect + to + and - to -.

Look at the pair of wires, they should be different somehow: color coding or a stripe on the insulation are the common ways.

 

[Corn]

What Dave said.

Just to add that that I've seen some very inconspicuous means for marking wire, such as writing printed or embossed every few inches or so. Take a very close look at the wire, you'll find the marking.

 

[sdifox]

You don't see the jacket colours at all? Usually red = + black = -

 

[vshah]

i think he can only see one end of the wire, and not where it is connected to the receiver. red is + and black is -

 

[mshan]

Maybe use one of those surround sound set up dvds where signal is sent to each speaker in phase and then out of phase?

If you wire incorrectly, it will be out of phase and may not sound right (speaker cone pushing in when it should be pushing out)?

http://www.thx.com/consumer/home-en...er/thx-optimizer/thx-optimizer-speaker-phase/

You probably need a correct baseline reference for making comparisons, so you may want to run a temporary run of speaker wire from avr to left and right fronts wired correctly as your reference for correct. Then reconnect in wall wire for one of the channels and see if it sounds same; if not, just reverse black and red connections at speaker end (probably want to mark each lead so you don't get confused). After that, center and surrounds can probably just use any of the THX Optimizer tracks available on some dvds and things like Avia or Home Theater Essentials.

 

[YOyoYOhowsDAjello]

Do you have any other insulated wires that would be long enough to run from the receiver to the spot where the unmarked wire comes out of the wall?

If so, you could hook up one end of the mystery speaker wire at the receiver and the speaker on the positive side. Then use your new wire to connect up the negative side.

If your speaker works at that point, you know you guessed right. If it doesn't work, switch which half of the mystery wire you're using at either the receiver or the speaker end. Mark that with a marker and now you have the strand labeled.

 

[simonizor]

Just plug it in and try it out. If it works, you've got it wired correctly, if it doesn't then you don't. It's not going to hurt anything if you plug it in incorrectly.

 

[sdifox]

Just plug it in and try it out. If it works, you've got it wired correctly, if it doesn't then you don't. It's not going to hurt anything if you plug it in incorrectly.

it will work either way. The question is will it work correctly.

 

[The Boston Dangler]

edit: sorry, misunderstood the problem

 

[YOyoYOhowsDAjello]

What receiver do you have?
Some receivers now have the ability to determine if there is a phase issue with speakers when doing auto-setup.

 

[vshah]

do you have a continuity tester? or an led and a battery?

 

[kornphlake]

Get an ohm meter and a long test lead, or a volt meter and a battery. I've seen two conductor wire that appears to be unmarked, but the insulation is a slightly different shape on one of the conductors, something like a rib in the insulation or a square shape on one conductor and a round shape on the other. I guess it's for blind audiophiles.

 

[YOyoYOhowsDAjello]

With my method, all you need is a wire

 

[vshah]

With my method, all you need is a wire

yeah, but ours have blinky lights and sounds!


regardless...almost every paired wire i've seen has some form of markings on the jacket.

 

[YOyoYOhowsDAjello]

yeah, but ours have blinky lights and sounds!


regardless...almost every paired wire i've seen has some form of markings on the jacket.

Hey, mine has sound too. The sound even indicates success

 

[MStele]

get a small battery and connect it to the speaker wires. If you have the polarity right, i.e. positive to positive, the speaker should extend out toward you. If you have it backwards, it will pull into the cabinet away from you. Also, using the wrong polarity will cause the sound to be thinner in general, but this is harder to quantifty with surround speakers since they don't tend to have much midrange.

 

[RupTheKid]

get a small battery and connect it to the speaker wires. If you have the polarity right, i.e. positive to positive, the speaker should extend out toward you. If you have it backwards, it will pull into the cabinet away from you. Also, using the wrong polarity will cause the sound to be thinner in general, but this is harder to quantifty with surround speakers since they don't tend to have much midrange.

Yep. 9V battery will work. Honestly though, in all practicality it makes zero difference to sound quality for HT application...movies do not preserve absolute phase in the soundtrack.

 

[Raduque]

regardless...almost every paired wire i've seen has some form of markings on the jacket.

I used to have a small roll of thick red paired wiring that doesn't have any +/- markings on it. It had a label on it that called it speaker patch cable. I ended up flatting out lengths of it, running my finger down one side of it, and tying knots in both ends so that a knot is either positive or negative however you hook it up.