Reversed Polarity Door Speakers

[Nighthawk]

So I run into this posted in a long stereo upgrade thread:
Metra 72-7902 for the dash
Metra 72-6514 for the doors, one thing to note if you do the doors, they are reverse polarity so the wires on the adapter need to be swapped. + to - , - to +.

I have the stock 6 spkr system. Upgraded all speakers. Infinity 6x9s in all doors. Bought the wire harnesses from Crutchfield. Although I would call it an upgrade, it’s not as good as I was hoping. I am thinking the 4 speakers are all wired backwards. As note, I gave the speakers and the harnesses to a local installer who has removed a lot of Ram door liners as he also tints. Not blaming him at all. I am wondering this, just what/where the reverse polarity is.

1. Is the Metra harness flawed?
2. Is the factory harness plug backwards from normal?

Without taking a panel back off, is there anyway to decide they are all backwards or not? To be honest the sound is still better than stock, Bass is decent, not great and clarity is also better. Can they be reversed and sound that good?

 

[Nighthawk]

Not that it matters but the speakers are Infinity Reference REF-9633ix

 

[Nails]

Been along time since I’ve been into the sound system. From what I’ve read around here.
A quick answer for you and your truck is your 6speaker system doesn’t have the amp to push it past stock speaker levels. So upgrading the speakers are good idea. Compared to the other systems that have higher level amp outputs it’s not going to be a huge difference but more quality. As you did state

 

[Patsy1099]

Short answer is it could be either the metra harness or the factory wiring. They make apps, speaker pop, speaker polarity, that attempt to send a sound file to your speakers and depending on the “pop”, it will tell you if you have the polarity reversed. I’ve read mixed reviews where some rave and others have had mixed results. It’s easiest to try one of those first by locating in App Store (or Android). The full proof way is to pull the door panels off and put a multimeter on the speaker terminals (with power turned on), set the multi to DC (200 setting) and if when you have the pos of the multi connected to the pos if the speaker (and the neg to neg), you get a “+” reading (like 1.7, 2.0, etc), it’s wired correctly. If the reading is negative, like -1.7, the the polarity is reversed and you have to either swap the pins in the metra harness or do what I did, swap the tails on the metra by snipping and resoldering.

One thing to note, some people here have left the polarity reversed, if it was reversed on their stock setup. Meaning, they kept the polarity the same, if it was reversed they kept it reversed and if it was not, they kept it that way. I took the other approach which was to make sure that everything was in-phase (matching polarity), regardless of whether the speaker in that particular stock location matched. I wanted everything in-phase. I have not had any issues with sound or ANC. I have not lost volume or sound. It’s plenty loud and crystal clear. This will also be dependent on the speakers you choose. I have so far only completed my dash and front doors, rears will be done when weather cooperates. I went with infinity ref all around (see my sig).

 

[Rick8325]

I was sent Metra 71-050 from Crutchfield for the doors. I was under the impression this resolves the polarity issue....? So confusing.

 

[Patsy1099]

I was sent Metra 71-050 from Crutchfield for the doors. I was under the impression this resolves the polarity issue....? So confusing.

Well it depends on what you mean by “resolves”. The only thing that harness does it lets you easily connect the wiring harness from the truck to the new speakers (with standard connectors) BUT the wiring in the Ram is confusing. The polarity from the trucks wiring diagram doesn’t always match (meaning the polarity is reversed). On top of that, the Metra Harness doesn’t seem to be consistent in its wiring, different models have the wires flipped. On top of THAT, the Ram has potential ANC issues that can creep up and cause a drowning noise if the new speakers aren’t wired “correctly” or wired (incorrectly) exactly like the old stock ones. So here are your choices:
- use the metra harness. Plug and play the new speakers. Cross your fingers. Drive and listen for drone before putting things back together
- test for polarity using a multimeter and either put all new speakers “in phase” using correct polarity OR put all speakers in using the exact same polarity as the one you are pulling out (if it’s in phase, install new one in phase, if it’s out of phase, install new one out of phase.

I personally installed install all of mine in phase and everything works perfectly.

 

[Rick8325]

Well it depends on what you mean by “resolves”. The only thing that harness does it lets you easily connect the wiring harness from the truck to the new speakers (with standard connectors) BUT the wiring in the Ram is confusing. The polarity from the trucks wiring diagram doesn’t always match (meaning the polarity is reversed). On top of that, the Metra Harness doesn’t seem to be consistent in its wiring, different models have the wires flipped. On top of THAT, the Ram has potential ANC issues that can creep up and cause a drowning noise if the new speakers aren’t wired “correctly” or wired (incorrectly) exactly like the old stock ones. So here are your choices:
- use the metra harness. Plug and play the new speakers. Cross your fingers. Drive and listen for drone before putting things back together
- test for polarity using a multimeter and either put all new speakers “in phase” using correct polarity OR put all speakers in using the exact same polarity as the one you are pulling out (if it’s in phase, install new one in phase, if it’s out of phase, install new one out of phase.

I personally installed install all of mine in phase and everything works perfectly.

I replaced my dash with Kickers the other day using Metra 72-7902 and have not had any issues. The sound was much improved. Now I'm afraid to do the doors lol.

 

[Patsy1099]

I replaced my dash with Kickers the other day using Metra 72-7902 and have not had any issues. The sound was much improved. Now I'm afraid to do the doors lol.

From what I’ve read you’d not likely hear a problem from the dash speakers. More likely to hear it from the doors. I could be wrong. Good news is that the dash speakers are so easy to pop out that you can correct them if you need to. You also need to be driving and get the rpms up, turn up the volume and then see if there are issues.

 

[Patsy1099]

For those of you replacing the dash speakers... do your replacements come with pre wired bass blockers? If not are you wiring in bass blockers? My Infinity Ref came with them but I had to solder them into the metra harness myself. I called Crutchfield and they strongly recommended I put them on to protect the 3.5s

 

[Rick8325]

For those of you replacing the dash speakers... do your replacements come with pre wired bass blockers? If not are you wiring in bass blockers? My Infinity Ref came with them but I had to solder them into the metra harness myself. I called Crutchfield and they strongly recommended I put them on to protect the 3.5s

Bought my Kicker 3.5’s through Crutchfield and they didn’t send any or recommend any additional purchases.

 

[Patsy1099]

Bought my Kicker 3.5’s through Crutchfield and they didn’t send any or recommend any additional purchases.

I wonder why. Seems like cheap insurance. Crutchfield even makes their own if the speakers didn’t come with them.

 

[rsonedecker]

71-050 "retains" the stock polarity (- to +). 72-6514 "switches" polarity back to + to +. However, you can repin either to be the opposite.

 

[Rick8325]

I received this from Crutchfield. I also read in another thread that the diagrams are wrong. Haven't ripped my door panels off yet but I'll check the polarity before installing.

 

[W13NY]

Installing my Kicker Dash Speakers today with the same metra speaker harness. Should be pretty easy and a big improvement from what I've read on here and some reviews.

 

[W13NY]

What should be easy isnt - anyone else have trouble getting the wiring harnesses to connect to the speakers? No matter how hard you push ive only gotten 1/4 to go in as of now. Doesnt make any sense.

*Edit - the harness from crutchfield was very bent on the inside of the plastic coating which caused all of the issues - not too thrilled about it but I got it to work finally.

 

[PorBoy]

I used Metra 72-7902 for my dash speakers ( JL Audio ) and no problems there. Won’t be doing anything door wise or anything audio in this truck.

 

[rsonedecker]

What should be easy isnt - anyone else have trouble getting the wiring harnesses to connect to the speakers? No matter how hard you push ive only gotten 1/4 to go in as of now. Doesnt make any sense.

*Edit - the harness from crutchfield was very bent on the inside of the plastic coating which caused all of the issues - not too thrilled about it but I got it to work finally.

Yeah, I had to put my finger bracing the terminal, and wiggle the connector while pushing hard. I finally stopped that, and it would put a pick in there and spread the harness end open a little, and then once I put it on the speaker terminal, I squeezed them tighter with pliers.

 

[W13NY]

I used Metra 72-7902 for my dash speakers ( JL Audio ) and no problems there. Won’t be doing anything door wise or anything audio in this truck.

Yeah I used the same ones and I dont know if I just got a bad set or what went on cause they were bent all out of whack. Got them to work after about 30 minutes of carefully toying with them - didnt want to break them and have to wait for new ones

 

[Phantom29]

I wonder why. Seems like cheap insurance. Crutchfield even makes their own if the speakers didn’t come with them.

Any recommendation for the kickers to add the bass blockers to them
150hz or 600hz?

 

[Jackham]

I have never found Crutchfield to make a mistake if I give them good data and talk to them while I install. One thing I always strive for is to put in more efficient speakers with excellent clarity. Then the head doesn't matter much. If you go with brute force you have to add amps, change out heads etc. It is definitely a more sophisticated approach. It takes a bit more book work, but worth every minute of effort.