subwoofer problems
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=126330
Printed Date: May 13, 2025 at 12:32 PM
Topic: subwoofer problems
Posted By: jkats91
Subject: subwoofer problems
Date Posted: February 27, 2011 at 1:12 AM
I have a JL 10W3V3 - 2 ohm ratings subwoofer in a ported box, I have done all the test to make sure it isn't blown i.e: hooked up a voltmeter and measured resistance, steady 2 ohm's and when pushing on the cone I get no harsh scratching noises. But there is something funny, when the woofer is pumping (playing), there is a rattle noise that is coming from it, most likely the cone. Is there anyone that is aware of the issue, or has had previous experience with this subwoofer
Replies:
Posted By: lspker
Date Posted: February 27, 2011 at 1:29 AM
Could be a few things, something rubbing, something lose under dust cap, torn spider, air leak around flange, magnet loose, or my personnel favorite voice ciol detached from forms. Start by good inspection, shake it, and check lead wires.....if bad they could give static sound.
Posted By: jkats91
Date Posted: February 27, 2011 at 1:35 AM
lead wires are fine, when shaken no sound is heard and again i reiterate that w/the voltmeter resistance is stable at 2 ohm's, could it just be a defective woofer that needs to be replaced all together or is it a quick fix? There is no way that it is blown....??
Posted By: i am an idiot
Date Posted: February 27, 2011 at 5:51 AM
Sounds like it is blown to me.
Quickly yet gently tap the center of the cone, do you hear the same rattle that you hear when it is playing?
Posted By: jkats91
Date Posted: February 27, 2011 at 9:14 AM
I did exactly as you said and the rattle doesn't exist it's just a normal thump..?
Posted By: i am an idiot
Date Posted: February 27, 2011 at 11:07 AM
Try it in a different box and connected to a different amplifier. If it still rattles in both situations, it is blown.
Posted By: jkats91
Date Posted: February 27, 2011 at 1:36 PM
i have connected it to a different amplifier and newer box and even had it connected to the amplifier w/out a box, and still the same rattle, even though it isn't "technically" blown is there a problem with the cone?
Posted By: DYohn
Date Posted: February 27, 2011 at 1:43 PM
jkats91 wrote:
i have connected it to a different amplifier and newer box and even had it connected to the amplifier w/out a box, and still the same rattle, even though it isn't "technically" blown is there a problem with the cone?
As said above, it is blown. Most likely what you're hearing is the voice coil rattling around and it has come unglued from the former. This is a symptom of either defective woofer or of over power or over heating most likely due to clipping. ------------- Support the12volt.com
Posted By: i am an idiot
Date Posted: February 27, 2011 at 3:54 PM
Technically, It is blown. It does not have an open voice coil, nor is the pole piece rubbing on the magnet, but it is blown.
Posted By: jkats91
Date Posted: February 27, 2011 at 7:04 PM
thank you guys for all of your committed time, effort and help to these forums!
Posted By: jkats91
Date Posted: February 27, 2011 at 7:05 PM
i do want to know though, what is "clipping"? and by "over powering" what do these actually mean?
Posted By: DYohn
Date Posted: February 27, 2011 at 11:32 PM
jkats91 wrote:
i do want to know though, what is "clipping"? and by "over powering" what do these actually mean?
Clipping is over-driving the amplifier, usually done in car audio by loading it with too low speaker impedance or turning the gain up too high. Over-powering is literally delivering too much power to the speaker which causes it to either overheat or to reach the mechanical limits ("hit the stops.") Clipping can be bad because it delivers DC to the speaker and delivers almost twice the normal amplifier rated power. It can over-heat the speaker, which leads to things like the voice coil braking loose (the symptom you describe.) ------------- Support the12volt.com
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