View Full Version : 2009 X2 Sub woofer
12-05-2011, 11:28 AM
the sub woofer right behind the drivers seat sounds like its loose and instead of the bass sound it sounds like the speaker is rattling the plastic covering..any ideas?
12-05-2011, 11:40 AM
From the backside run your fingers around the termination of the rubber surround. Its not fragile. You may discover that the surround has become separated from the either the cone or the frame.
Remove the front grill insert and press in on the center of the cone with centered pressure. If you hear and feel rubbing of the interior parts then you know the speaker is damaged.
However, you can cause this same result by pushing in off center and when there is no real speaker problem. But the test will not be damaging to a woofer.
Look for if the cone is frozen in position.
Feel and look in behind the speaker. If something as harmless os a piece of paper is lodged between the back side of the cone and the basket/frame interior or touching the flexible tinsel leads, it can make an inordinate amount of racket.
12-05-2011, 11:52 AM
One or two more things...
You can have a condition where the noise is created by an intermitent internal connection between the voice coil wire and the tinsel lead. Sometimes if you press in lightly on the center of the cone while it is playing the noise will cease.
Some of these conditions that I described are repairable by JL Audio and would not require a speaker replacement. Others are a sure sign you need a new woofer.
Before getting a repair or replacement you have got to check both the subwoofer lowpass crossover frequency and the bass boost setting on the amplifier. A free-air or IB woofer crossover should be set around 120 Hz which will automatically necessitate that you gain down the sub as you will have too much sub output otherwise. An IB woofer should have zero bass boost applied.