Speakers +/- , How to test for this?

[XJ_in_Canada]

I just installed a new head unit (Sony Xplod MP3) in today and the instructions mention that the wires to the speakers should be correctly attached to the positive and the negative of the speaker.

How do I test for this on the speakers? I have never heard of speakers having a +/- side.

Can anyone elaborate on this?

ThanX

 

[Dirk Funk]

If the speaker is wired incorrectly, the cone of the speaker will move in when it is meant to move out, and visa versa. It is called being 180 degrees out of phase. It will sound relatively the same, but the bass may get cancelled out in some locations of the jeep because the sound waves may collide and create destructive interference.

The positive end is usually the larger terminal and the negative the smaller on the speaker. The negative wire usually has a stripe on it as well. I'm not 100% sure, but I think if you touch a 9 volt battery to the speaker, and the polarity is correct, the cone will move out opposed to moving in when it is wired out of phase.

Hope this helps you out.

 

[imma honky]

Where did you get your unit? did you also replace your speakers? I got mine from crutchfield, they gave me everything i needed. Wireing harnesses, diagrams and all. Be a little more specific on what you are trying to test. The actuall speakers or whether the head unit is hooked up right?

 

[Boz88xj]

It wont makek ANY difference.

Theoreticaly, if the two speakers are out pf phase, there could be dead spots... but that doesnt ake into account sound bouncig off other things.. dont worry about it.

 

[Matthew Currie]

I have to disagree with Boz on this one. Phasing will often make a very noticeable difference. But as long as you wire all the speakers the same it doesn't matter which way round they all are.

If you have some doubt about whether they're in phase, it should be possible to test by listening. Play a source that is heavy on the lower end, and preferably monaural. If you reverse the speaker on one side, you'll hear a difference in the bass. The arrangement with the greater bass is correct. It can be a little harder to get phasing right between front and rear, but you can do it too, with the balance all the way to one side.

 

[ZPD]

There is a much simpler way of determining the +/- of a speaker.
Take a AA battery and hook it up to the the speaker. If the + is hooked to the + and the - to the - then the cone will protrude. If it retracts then you have backwards. I used this method all the time back in the day.

 

[AussieXJ]

I think it would be a rare speaker indeed that did not indicate the polarity either on or near the terminals. Sometimes the + or - sign will be stamped in to the metal of the terminal itself. Also if the terminals are different sizes (widths) as is not unusual the larger one is probably positive. One other way of indicating polarity will be a dot of paint on or near the positive connector.

 

[ChEwBaCcA]

Sorry Boz you are posting SPOBI...... It does matter and matters a LOT if your powering speakers w/ an amp and paying tall cash for good sounds. Like others have said the speaker will be out of phase and the cone will be pulled in when it should pound outward!

Why spend money on car audio and then hook it up like a hill rod!

peace
chewy

 

[Moto]

If you only replaced the head unit and are questioning which speakers wires were + and -, I am assuming that this is on the back of the head unit and that this is an issue because you dodn't know which wires coming up into the dash are which. You can try the whole battery thing but my suggestion would be to just buy the correct connector that would have plugged into your factory harness. It is nice because it is all labled and if you decide to change head units in the future, you won't have to cut back the Jeep wires any shorter and they only cost cheap $. If that isn't the issue then pay no attention and either try the battery method because when you cut off the stock connector going to your stock speakers there really isn't a good way to tell unless you have a wiring diagram that depics + and - or you use the battery method. Hooking up the speakers backwards probably isn't going to destory your Jeep and catch fire or anything, but they may not sound right and in some cases can make the amp inside of your head unit have a harder time powering them because when it wants to push them out it is pulling them in vice versa which can make it work a bit harder.

 

[Boz88xj]

Sorry Boz you are posting SPOBI...... It does matter and matters a LOT if your powering speakers w/ an amp and paying tall cash for good sounds. Like others have said the speaker will be out of phase and the cone will be pulled in when it should pound outward!

Why spend money on car audio and then hook it up like a hill rod!

peace
chewy

OK, im sure I could have been off on this.

Ive never payed any attention, mainly because my stepdad was/is an audiophile, and when I wasked him when I put in my speakers he said that the phasing would be out, but that it would still work.

I guess there is a difference between working and working well, but I've noticed nothing wrong with my setup, so maybe I was lucky, or just dont have a good ear.

Then again im not running an amp, I already spent too much on my systen, last thing I need is an amp!