• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

JBL LX44G right speaker polarity is incorrect!

bikingbuddha

bikingbuddha

Well-Known Member
About a month back I bought a pair of second hand JBL LX44G speakers, they did sound good but for some reason felt that bass isn't right. Today i thought i'd check the polarity of the speakers, so I grabbed a 1.5V battery and checked. One speaker, the woofer moves correctly when i connect Positive to Positive terminal and Negative to Negative terminal. The other speaker it moves incorrectly. Which menas when i connect Negative to negative and positive to positive the woofer moves inwards.

I was thinking of removing the woofer tomorrow and checking if someone has changed the polarity by a mistake. From the looks of it, the drivers haven't been removed (but we may never know).

I just want to know if this is what company orignally designed them to be? one speaker has changed polarity so the woofer moves inwards?
 
Register to hide this ad
It's not correct, but it happens. The question is Is the "entire speaker" out of phase, or just the driver.

JBL (and others) sometimes gets the polarity of the woofers wrong in that the magnetic field is actually reversed from the norm so that when you wire it properly, it is reversed.

How can you tell? Use a compass and approach the speaker from the front center and watch the needle. Both woofers should be the same and sometimes aren't. If they aren't, you need to flip the polatity at the woofer's internal wires.
 
toddalin said:
It's not correct, but it happens. The question is Is the "entire speaker" out of phase, or just the driver.

JBL (and others) sometimes gets the polarity of the woofers wrong in that the magnetic field is actually reversed from the norm so that when you wire it properly, it is reversed.

How can you tell? Use a compass and approach the speaker from the front center and watch the needle. Both woofers should be the same and sometimes aren't. If they aren't, you need to flip the polatity at the woofer's internal wires.
Click to expand...
My bad english, it is not entirely clear to me but thanks a lot for the info.

Should i approach speakers with a compass while they are running?

Also is it normal for them to flip the polarity? Is that what factory intended?
 
No, speakers are off. You want to check the direction of the magnetic field to make sure tha tboth woofers are the same.

A JBL reconer reports that about 1 in 50 JBL woofers is "flipped". Other brands may have even more. If the magnetic field is flipped, then the polarity of the connection must also be "flipped" to compensate for it.
 
toddalin said:
No, speakers are off. You want to check the direction of the magnetic field to make sure tha tboth woofers are the same.

A JBL reconer reports that about 1 in 50 JBL woofers is "flipped". Other brands may have even more. If the magnetic field is flipped, then the polarity of the connection must also be "flipped" to compensate for it.
Click to expand...
So I just simply take a compass closer to the woofer and the which ever hand that points towards the speaker should be same on both woofers...? Alright I can do that.
This polarity issue is a factory fault then! I will definitely check. In my case one of the speakers woofer driver bounce inwardly when I supplied power to the + and - in the correct manner. When I flip it, the woofer moves correctly.

Also does this compass test apply for mid driver as well as metal dome tweeter?
 
toddalin said:
No, speakers are off. You want to check the direction of the magnetic field to make sure tha tboth woofers are the same.

A JBL reconer reports that about 1 in 50 JBL woofers is "flipped". Other brands may have even more. If the magnetic field is flipped, then the polarity of the connection must also be "flipped" to compensate for it.
Click to expand...

I just checked using a compass. Both are same, the same colored hand points toward both the speakers. but one of the speakers moves backwards when i supply the power correctly according to the + and - (Red and Black), so that means the woofer is somehow wired incorrectly. right?
 
Most likely the leads are swaped feeding the woofer. Open it up and take a look. Not a big deal. Hold your hand near the screwdriver tip so you dont poke a hole in the surrounds bt accident. You could open both speakers and compare.
 
SmileyFaceEQ said:
Most likely the leads are swaped feeding the woofer. Open it up and take a look. Not a big deal. Hold your hand near the screwdriver tip so you dont poke a hole in the surrounds bt accident. You could open both speakers and compare.
Click to expand...
I am looking for a right screw driver to do this, I will update as soon as I opened it up.
 
bikingbuddha said:
I just checked using a compass. Both are same, the same colored hand points toward both the speakers. but one of the speakers moves backwards when i supply the power correctly according to the + and - (Red and Black), so that means the woofer is somehow wired incorrectly. right?
Click to expand...
That's good news. Yes, it sounds like either the woofer is wired backward, or the leads that go into the crossover are backwards, in which case all drivers are reversed.

Are you sure that the wire aren't switched over at the back of the amp?
 
Last edited:
These are 30+ year old speakers with foam surrounds right? If the surrounds look good then odds are someone replaced them already. Which is probably when the wires got swapped on the woofer.

I mean they could have come from the factory like that, but odds are someone had the woofer out at some point and hooked it back up wrong.
 
You must log in or register to reply here.
Back
Top Bottom