Subs out of sync

[michaelproeber]

Hi all, my 2 12” Kicker 10C124 are not moving together. They’re in a shared airspace sealed box. Both are working and they’re not dangerously out of phase afaik (but I’m new to car audio), you can just see one is moving a little different. They’re powered at 2 ohms by a Alpine MRP-M450 mono amp. One of the subs is measuring 4 ohms, and the other 5 ohms. Is that one faulty? Together it’s 3 ohms. I also verified the polarity with both.

Click to read more...

 

[1aespinoza 10+ year member]

One of the subs is measuring 4 ohms, and the other 5 ohms

The 5 Ohms sub's resistance is not letting as much power pass through it as the 4 Ohms sub. Therefore it will move less. Just like a light bulb, a 1 Ohm bulb will burn brighter than a 5 Ohm bulb.

 

[audiobaun 5,000+ posts]

I would wire up that 5 ohm sub to the amp supply first and the 4 ohm secondary may make a bit of difference. Those are actually some pretty decent subs. I put 4 of them in one my cousins 78 truck and they got down pretty good. Run them
https://www.the12volt.com/caraudio/subwoofer-wiring-diagrams.asp?Q=2&I=41

 

[winkychevelle 10+ year member]

Yea I would swap out the sub that reads 5ohm. Or at least check all the connections to see if you have added resistance in the wiring leading to the amp. A 1ohm difference between 2 speakers is quite large

 

[hispls 5,000+ posts]

Hi all, my 2 12” Kicker 10C124 are not moving together. They’re in a shared airspace sealed box. Both are working and they’re not dangerously out of phase afaik (but I’m new to car audio), you can just see one is moving a little different. They’re powered at 2 ohms by a Alpine MRP-M450 mono amp. One of the subs is measuring 4 ohms, and the other 5 ohms. Is that one faulty? Together it’s 3 ohms. I also verified the polarity with both.

Are you certain these subs are identical? Speakers with the same model name may be of different revisions and not identical specs. What kind of multimeter do you use? Are you measuring impedance in a quiet place out of the wind? Let's see some pictures of the box as it sits in your vehicle.