Speaker Phase - Front vs Rear

[pcolony]

Hello,

I recently had a new head unit and new front component speakers installed by a local car audio shop. I'm not proficient in adjusting much more than balance, bass & treble.

Head unit: New Alpine iLX-W650​

Front Speakers: New Focal Access 6.5 component​

Rear Speakers: Old Infinity kappa 6.5 coaxial (from 2004)​

Amp: Old Alpine MRV-F450 (also from 2004)​

After playing around with sound settings, I came to the conclusion the sound was worse than before replacing the old Infinity kappa front components with the new Focal components (which I was expecting to be some sort of improvement over the old front Infinity kappa coaxial speakers).

I installed the Speaker Pop app on my iphone and tested phase. The first thing I discovered was, they had the right and left channels reversed. I was able to quickly fix this at the amp. The next thing I discovered were the front speakers were out of phase, I was also able to fix this at the amp. With this, the sound had improved.

Then I tested the rear speakers, which are not wired to the amp and just get their power directly from the head unit. The channels are properly balanced, but both left & right show negative phase with the Speaker Pop app.

So, my question is... if both rear left & right are negative, but both fronts are positive, is my sound quality suffering? These aren't as easy to fix, since the wiring is behind the head unit, so I'm looking to find out if it's worth it to pull it out to swap the -/+ wires on each of the rear speakers.

Any insight is appreciated, thanks!

Patrick

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[Squirrel!]

Personally, I would try another app and see if the results are similar and then make your executive decisions on swapping wires around.

 

[nauc 10+ year member]

setup is huge. and i wouldnt use rear speakers, usually just screws up the sq

what vehicle?

id tune it all yourself. reset the amp gain etc. we can help

 

[pcolony]

Thanks for the responses. I tested the Speaker Pop app on various other speakers (other cars and in my home) and it reported them all in phase, so I'm feeling pretty comfortable that it's accurate, since it's been right with those, in addition to the out of phase it reported in this car.

The car is a 1995 Acura Integra 2-door.

I'm aware people often recommend only running the front speakers, and I've tried that, but it always sounds less full to me then with the rears on too. Also, even if I did use only the fronts, I want to have the rears wired correctly regardless (this sort of things bugs me).

I pulled the center console so I can get a visual on the wiring and if I'd even be able to correct the polarity without removing the head unit, and it's clear there's not enough room. I also see they cut the factory harness and capped the aftermarket harness directly to the factory wiring. So now this has escalated to me ordering the male & female Metra harnesses, to get the factory wiring harness restored.

I'm still searching for the answer on sound quality impact of the rears both being wired in reverse polarity (mostly out of curiosity). And I'm also on a mission to wire in the Metra harness to the factory wiring. This car is a hobby car for me, that I use to give me projects to do over the weekends, so I don't mind any of this... it's part of the fun.

I need advise on how to remove the aftermarket dash kit now. It doesn't seem like they did that great of an install, because the bottom of the radio pushes out about 1/4 an inch, and only the top is secured by the tabs that lock it into place. Do you normally have to sacrifice the tabs (break them off) to get these dash kits out? it appears just the top 2 tabs are holding it in.

Thanks!

Patrick

 

[staan]

Pan left and fade between front and back if there is more bass they are in phase if less they are out. It sounds like whoever installed it was luckily correct on reversing the phase to the front to match the rear, but were incredibly stupid to have the front right and left out of phase.

 

[Squirrel!]

It's always been my understanding out of phase basically just messes with the bass.