Sponsored

Metra Speaker Harness Polarity (updated)

OP
OP
Jebiruph

Jebiruph

Well-Known Member
First Name
Jerry
Joined
Feb 18, 2018
Threads
56
Messages
2,133
Reaction score
2,711
Location
Iowa
Vehicle(s)
2018 JLU, 2019 KL, 2020 JT
Hoping that I can tag onto this. I am planning to replace all of the speakers in all the locations in my JT Gladiator, which are identical to a 4 dr JL Wrangler.

Are people saying that _both_ the 72-7902 and the 72-6514 flip the polarity? If so the speakers should all stay in phase, and it's usually not a big deal if the phase of all of the speakers together are flipped as long as they are _all_ flipped, together.

Thanks!
They both flip and you are right, changing them all keeps them in phase.
Sponsored

 

kd1yt

Member
First Name
Trevor
Joined
Sep 17, 2019
Threads
1
Messages
7
Reaction score
1
Location
Vermont
Vehicle(s)
2020 JT Gladiator
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.
 

robd1438

Well-Known Member
First Name
Rob
Joined
Nov 15, 2018
Threads
24
Messages
164
Reaction score
188
Location
Portland, CT
Vehicle(s)
2018 Wrangler JLU MOAB
Vehicle Showcase
1
Front left dash for me had gray/yellow as positive; seems to be different for different folks. I used volt meter to quadruple check.
 

StaindReality

Well-Known Member
First Name
David
Joined
Aug 11, 2018
Threads
20
Messages
116
Reaction score
44
Location
Kansasncity
Vehicle(s)
Ram 1500 crew cab black out
Thanks. What's odd about those diagrams is the actual wire colors for the roll bar speakers in my 2020 JL are white and grey. So, I don't know how that aligns with the color codes on the schematic. Frustrating.
Same here. So here is my problem. The metra Barnes would not fit so I clipped it and the Jl harness off and just wired them together for my infinities for the 3.5. I assumed white was positive and grey was negative. So I hooked them up that way. White to white to positive. Grey to black to positive. Now after reading this post. I think I may have reversed it.
So does anyone know for sure on sb. Is the grey wire actually positive and white negative.
 

Sponsored

StaindReality

Well-Known Member
First Name
David
Joined
Aug 11, 2018
Threads
20
Messages
116
Reaction score
44
Location
Kansasncity
Vehicle(s)
Ram 1500 crew cab black out
Thanks. Trial and error revealed that in my JL the white factory wires in the roll bar are positive and the grey are negative.
Sorry. This answered my question. Seems I did do it right. Didn’t notice this post the first time. I also did white to white to positive. Etc.
 

Pdiehm

Well-Known Member
First Name
Paul
Joined
Dec 25, 2019
Threads
32
Messages
230
Reaction score
94
Location
Newark, DE
Vehicle(s)
2018 Jeep Wrangler Unlimited Sahara
Occupation
AML Investigator
I am electronically stupid but am replacing the 3.5” speakers soon. How do you test this stuff out to determine if the adapter wires need to be flipped?
 

sknyfats

Active Member
First Name
Fred
Joined
May 20, 2020
Threads
3
Messages
41
Reaction score
17
Location
USA
Vehicle(s)
2020 JL Wrangler Willys 2 Door
I am electronically stupid but am replacing the 3.5” speakers soon. How do you test this stuff out to determine if the adapter wires need to be flipped?
A little late on this thread but safest bet is to do the 9v battery speaker polarity test. Google that. I’ve found that what is shown as positive/negative on the wiring diagram Is not correct, as is the assumption that the capacitor side of the stock speakers being positive is not correct.
I confirmed positive for my stock speakers was the non-capacitor side and made sure to hook up my new speakers positive to the same wire that was originally connected to that terminal.
I did the test on all 4 3.5” speakers just for good measure when replacing them.
 

Pdiehm

Well-Known Member
First Name
Paul
Joined
Dec 25, 2019
Threads
32
Messages
230
Reaction score
94
Location
Newark, DE
Vehicle(s)
2018 Jeep Wrangler Unlimited Sahara
Occupation
AML Investigator
A little late on this thread but safest bet is to do the 9v battery speaker polarity test. Google that. I’ve found that what is shown as positive/negative on the wiring diagram Is not correct, as is the assumption that the capacitor side of the stock speakers being positive is not correct.
I confirmed positive for my stock speakers was the non-capacitor side and made sure to hook up my new speakers positive to the same wire that was originally connected to that terminal.
I did the test on all 4 3.5” speakers just for good measure when replacing them.
right. You do that on the new speaker...but how do you know if the polarity on the harness is reversed?

i guess that is what I am asking
 

Sector281411

Well-Known Member
First Name
Greg
Joined
Jul 28, 2019
Threads
11
Messages
103
Reaction score
141
Location
Melissa, TX
Vehicle(s)
2021 JT Gladiator Willy's Edition
I recently replaced my dash and knee speakers and the adapters for the dash from Metra were correct, as well as the adapters for the knee speakers that came with the Metra pods.
 

Sponsored

sknyfats

Active Member
First Name
Fred
Joined
May 20, 2020
Threads
3
Messages
41
Reaction score
17
Location
USA
Vehicle(s)
2020 JL Wrangler Willys 2 Door
right. You do that on the new speaker...but how do you know if the polarity on the harness is reversed?

i guess that is what I am asking
Before disconnecting the old speakers, I looked to see what color wire was connected to the capacitor side and what was on the other.
Then I removed the speaker and did the battery test so it told me which side was positive and which was negative.
Then I hooked the new speaker up based on my findings. My new speakers have built in crossovers with clearly marked + and -.
I’m making an assumption that the original wiring was correct to begin with and just connecting the new speaker to what was on the old stock positive terminal.
 

oceanblue2019

Well-Known Member
First Name
John
Joined
Apr 13, 2019
Threads
18
Messages
3,099
Reaction score
4,759
Location
Maryland
Vehicle(s)
2019 JLUR 2.0L Auto
Occupation
Metrology
Hoping that I can tag onto this. I am planning to replace all of the speakers in all the locations in my JT Gladiator, which are identical to a 4 dr JL Wrangler.

Are people saying that _both_ the 72-7902 and the 72-6514 flip the polarity? If so the speakers should all stay in phase, and it's usually not a big deal if the phase of all of the speakers together are flipped as long as they are _all_ flipped, together.

Thanks!
ANC messes that up
 

Crusifix

Well-Known Member
First Name
Jeff
Joined
Mar 8, 2019
Threads
20
Messages
739
Reaction score
1,299
Location
West Virginia
Vehicle(s)
2019 JLU Rubicon 2.0T Hurricane
This thread ended up all over the place... My ADD brain couldn't follow what the final verdict was. So we need to flip the wires on the 72-6514 and the 72-7902 harnesses?
 

cride1

Well-Known Member
First Name
Chris
Joined
Jul 27, 2020
Threads
6
Messages
54
Reaction score
25
Location
63401
Vehicle(s)
2018 Jeep Wrangler JLU Rubicon
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.

Sponsored

 
 



Top