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Mark #2
01-21-2008, 08:02 PM
Can you put a voltmeter on the speaker wires and tell which one is the positive and negative wire?

SILVER2000SVT
01-21-2008, 08:25 PM
It's an AC signal so, no... If the wires are connected to a speaker you can check them by touching them to a 9v or cordless drill battery. If the speaker moves out the wires match the polarity as connected to the battery.

You can also tell if speakers are in phase by listening. This takes a little bit of a trained ear but I'll try and explain it. Adjust the balance or fader so that you are only comparing 2 speakers at a time. Sit equally inbetween the speakers. If the speakers are out of phase you can turn your head back and forward and the music will sound like it comes from different areas as you turn your head. If they are in phase the music will always tend to sound like it's coming from the center.

Another method is to fade from one speaker to the next, if the speakers are in phase they will tend to be louder and have a more full sound (bass) when both speakers are playing vs either one playing alone. If the speakers are out of phase the opposite is true and when either of speakers are playing by themselves the sound will be more full than when both speakers are playing together.

Mark #2
01-21-2008, 08:34 PM
It's an AC signal so, no... If the wires are connected to a speaker you can check them by touching them to a 9v or cordless drill battery. If the speaker moves out the wires match the polarity as connected to the battery.

You can also tell if speakers are in phase by listening. This takes a little bit of a trained ear but I'll try and explain it. Adjust the balance or fader so that you are only comparing 2 speakers at a time. Sit equally inbetween the speakers. If the speakers are out of phase you can turn your head back and forward and the music will sound like it comes from different areas as you turn your head. If they are in phase the music will always tend to sound like it's coming from the center.

Another method is to fade from one speaker to the next, if the speakers are in phase they will tend to be louder and have a more full sound (bass) when both speakers are playing vs either one playing alone. If the speakers are out of phase the opposite is true and when either of speakers are playing by themselves the sound will be more full than when both speakers are playing together.

Thanks,

SILVER2000SVT
01-21-2008, 08:46 PM
Thanks, my meter has an AC setting, so couldn't you tell that way if they are in phase?

Since it's AC, the current and voltage on the speaker wires is changing from negative to positive at the frequeny of the music. There's nothing you can measure to differentiate the two because both wires would read the same. The negative and positive on speakers is to create a reference so that all the speakers are functioning together. It doesn't matter if all the speakers were backward as long as they are all correct to each other.

Mark #2
01-21-2008, 09:10 PM
Since it's AC, the current and voltage on the speaker wires is changing from negative to positive at the frequeny of the music. There's nothing you can measure to differentiate the two because both wires would read the same. The negative and positive on speakers is to create a reference so that all the speakers are functioning together. It doesn't matter if all the speakers were backward as long as they are all correct to each other.

Fully understand.
Thanks for your inputs.

Back to soldering wires on the K5, the stock radio only lasted 20 years.:flaming:

SILVER2000SVT
01-21-2008, 10:24 PM
Oh your working on a chevy, why didn't you say so? Chevy speaker wire colors have been the same for 40 years.

Lighter colors are positive in the front (tan and light green) and darker colors are positive in the rear (dark blue and brown).

Here's a generic chevy link they are all the same:

http://www.the12volt.com/installbay/stereodetail/510.html