Metra Speaker Harness Polarity (updated)

[Jebiruph]

Here is a video where 5 Star is replacing the 3.5" speakers in a JT. They do some checking of polarity. The also come to the conclusion that the side with the capacitor is negative. I assume this would be the same across the JL and JT. As they say, you can look at the wire in the harness that mates up with the side with the capacitor to double check. They don't use the Metra harnesses, it looks like they splice their own wires in. They also have a video on replacing the knee speakers in a JT. Also note they do not use the capacitor that comes with the Alpine speakers.

Their explanation for not using the capacitor applies to systems with the factory amplifier. Since the factory amplifier may already be filtering frequencies to individual speakers, the capacitor isn't doing anything anyway. For people like me with the 5" and no amplifier, the capacitor should help.

Sponsored

 

[sabharad]

I found this picture on the reviews on the Crutchfield site.
https://images.crutchfieldonline.co...DONE/6724dd2c-5b0f-4d08-bd98-84e446ce660f.jpg

IS this one wired correctly or are the black/white cables connected to the speaker backwards?

I was going to follow this pic.

 

[RedundanT]

I found this picture on the reviews on the Crutchfield site.
https://images.crutchfieldonline.co...DONE/6724dd2c-5b0f-4d08-bd98-84e446ce660f.jpg

IS this one wired correctly or are the black/white cables connected to the speaker backwards?

I was going to follow this pic.

That shows the Alpine replacement/upgrade speakers for the sound bar. I would hope Alpine knew the situation and wired accordingly. HOWEVER, MB Quart will include a harness that has the +/- reversed so it will have proper polarity. The Metra ones are WRONG.

 

[sabharad]

That shows the Alpine replacement/upgrade speakers for the sound bar. I would hope Alpine knew the situation and wired accordingly. HOWEVER, MB Quart will include a harness that has the +/- reversed so it will have proper polarity. The Metra ones are WRONG.

Crutchfield provides the metra harness for the alpine speaker, hence me asking. Does that look right or wrong to you in the pic?

 

[SH556JL]

Crutchfield provides the metra harness for the alpine speaker, hence me asking. Does that look right or wrong to you in the pic?

I was a bit confused by the pic, as I just got done installing them and only had to plug in one wire harness instead of the two originally. I’m not an audiophile and this is my first ever system, so I followed the directions provided. But I read the comments associated with that picture and apparently (s)he used the Metra harness to bypass the cross over because (s)he has the factory Alpine. Out of the box, it’s already wired into the built in cross over (see attached picture below).

But now I am wondering if I have this issue as I ordered the Metra pods when installing my Alpine R-S65.2 and according to Crutchfield the 72-6514 was supplied with them...

 

[overboosted]

So quick question. I put in some Infinity 3.5"s in the corner dash over a year ago and used the speaker pop app and did not have to change the Metra plug. I have the Alpine Premium. The Grey/Yellow is going to the white on the Metra. Wiring diagram says Grey/Yellow is negative, but when I pop out the speaker, play music, and tap my Fluke 117 on there, red lead on + and black on -, I get a positive reading on the mulitmeter. That should be the final judge right? So I am good and the wiring diagram is wrong? WTH?

 

[oceanblue2019]

So quick question. I put in some Infinity 3.5"s in the corner dash over a year ago and used the speaker pop app and did not have to change the Metra plug. I have the Alpine Premium. The Grey/Yellow is going to the white on the Metra. Wiring diagram says Grey/Yellow is negative, but when I pop out the speaker, play music, and tap my Fluke 117 on there, red lead on + and black on -, I get a positive reading on the mulitmeter. That should be the final judge right? So I am good and the wiring diagram is wrong? WTH?

SpeakerPop or another tester like that is the "truth" and how most pro's setup a system.

 

[oceanblue2019]

Speaker crossover electrolytic caps are what are called nonpolarized or bipolar- the audio signal is alternating current and so they don't have a steady +/- . Using a standard (non-nonpolar) cap in a crossover application is a recipe for problems, and capacitor failure (and sometimes speaker failure because then the bass is no longer blocked from speakers not meant to handle a lot of bass). Phasing may matter with some source material, but try some time with a home stereo, one pair of speakers, switching the phase (making sure you keep both speakers in phase with each other). You may hear nearly nothing you can detect and a lot of audio equipment isn't even that meticulous about maintaining absolute phase. Low bass may matter more than higher frequencies, which is why subwoofer amps often do have switches or knobs for phasing.

Having speakers out of phase with each other within a system is a problem, although with some crossovers you actually _need_ to invert phasing of some of the drivers because some crossovers (usually only more complex ones, not just a series cap) actually introduce their own phase shifts.

Yes, and this is why using something like speaker pop is the right way to test as it is the true response of the speaker you are measuring.

 

[overboosted]

Thanks.

 

[jim00]

I installed the Kenwood Excelon KFC-X3C speakers in the dash location. I ordered from Crutchfield and they include adapters for free, which in this case was the Metra 72-7902 Speaker Wiring Adapter.
I used the AudioControl Mobile Tools 4.0.0 app but Studio Six Digital to test the polarity of all the speaker locations (except sub) on my 2021 JLU. I used the Studio Six Digital sample files to send the speaker pop test tone (files here https://studiosixdigital.com/support/downloads-2/).
All speakers except the dash had out of phase / reverse polarity (“-” on the app). When I installed the Kenwood speakers using the adapter mentioned above they tested in the app as normal phase / positive polarity. Because of this, I did not need to modify the adapter wiring. It is interesting that folks seem to get different results, as seen in this video.

 

[Jebiruph]

I installed the Kenwood Excelon KFC-X3C speakers in the dash location. I ordered from Crutchfield and they include adapters for free, which in this case was the Metra 72-7902 Speaker Wiring Adapter.
I used the AudioControl Mobile Tools 4.0.0 app but Studio Six Digital to test the polarity of all the speaker locations (except sub) on my 2021 JLU. I used the Studio Six Digital sample files to send the speaker pop test tone (files here https://studiosixdigital.com/support/downloads-2/).
All speakers except the dash had out of phase / reverse polarity (“-” on the app). When I installed the Kenwood speakers using the adapter mentioned above they tested in the app as normal phase / positive polarity. Because of this, I did not need to modify the adapter wiring. It is interesting that folks seem to get different results, as seen in this video.

The variety of results from all the polarity testing does get confusing. I wasn't even aware there was a way to test for this when I started this thread, I was going by how it sounded and swapping the Metra adapter wires made an obvious improvement with my base system.

If I'm following your post correctly, your dash speakers are wired with positive polarity and everything else is negative polarity. If that's the case, you may want to rewire the dash for negative polarity. Individual speaker polarity doesn't matter, they should just all be positive or all negative.

 

[jim00]

The variety of results from all the polarity testing does get confusing. I wasn't even aware there was a way to test for this when I started this thread, I was going by how it sounded and swapping the Metra adapter wires made an obvious improvement with my base system.

If I'm following your post correctly, your dash speakers are wired with positive polarity and everything else is negative polarity. If that's the case, you may want to rewire the dash for negative polarity. Individual speaker polarity doesn't matter, they should just all be positive or all negative.

I am not sure, it seems like the video I linked and others say they do that on purpose to achieve the sound needed. I think in the Metra instructions it says that tweeters can be done in any polarity for example (these aren't just tweeters in this case).

 

[Jebiruph]

I am not sure, it seems like the video I linked and others say they do that on purpose to achieve the sound needed. I think in the Metra instructions it says that tweeters can be done in any polarity for example (these aren't just tweeters in this case).

Upgrading from the factory speakers can affect the factory sound engineering and you might be better off following industry standards. It won't hurt to swap the wires and see if it sounds better. I also recommend stuffing some poly fil behind the dash speakers, I noticed my upgraded speakers generated sound inside the dash which had a negative impact.

 

[TPH]

Changed my Metra wire harness (flipped the negative and positive) and music quality improved. Ironically, I lost volume with the wrong polarity. I had installed Kenwood speakers in the dash and sound bar.

 

[EricP]

Ok, so without testing anything, I rewired the metro 72-7902 adapters to swap the spade connectors and add a bass blocker (attempts to remove pins from connector housing didn’t yield with my available driver, so snipping I went). Used those heat gun shrink tube / solder connectors and things couldn’t have been easier.

Installed to my Kicker 47ksc3504 3.5” speakers and some fiber-fill for the upgrade and things sounded great. As people noted, moved the fader to the back 2 and things sound AMAZING.

Cant beat the improvement for how little it costs.

Sponsored