jl sub, testing, ohms, enclosure

not sure maybe the sub is blown....i have a jl 10w6v2d2 sub in a custom sealed enclosure. had it for maybe two years +. its powered by a bazooka amp and its been good for the last two years. i put it into my integra that i just bought and it worked good for about couple weeks. now when i turn it up i hear kind of rattline noise coming from the sub. not sure if something is loose inside. or if the sub is blown. the sub still kicks hard but when volume is turned up it has that rattline noise from the box. not all the time and not all bass...only certain ones. is the VC loveed up? i did push the cone in and out a little bit no scraping, no rattle, or anything. the terminals going to VC are not touching. so no short. so i'm guessing its the enclosure. o yea so i took the sub out and turned it on with out it in the enclosure and i no longer hear the rattle or loose. sounds ok but again i'm not sure since the sub has to be in an enclosure. but as soon as i put the sub back into the closre just a little bit i hear it rattle again. so im guessing its the enclosre. its also like that when i remove the terminal outputs from the box. the one the speaker wires connects to the amp. when i leave it in, it rattles. when i take it out and play the sub it has no rattl?e

Sounds like the enclosure to me. Try pounding on the enclosure with you fist. Its barbaric but it works. If that dose not lead you to the problem try making a mechanics stethoscope. Get your hands on a piece of vinyl tubing (like the kind you use for a fish tank that you can get at a hardware store) and hold one side to your ear and use the other end to listen for problems on the box surface. When you reach a point of failure (break in a joint) you will hear the problem magnified. This makes it easy to pin point the problem.

Based on what you describe, I'd guess what you are hearing is the amplifier clipping.  It can sound a lot like a rattle.  And out of the enclosure you wouldn't hear it since you wouldn't be turning it up as high to achieve the same excursion level.  Here's a link to a video I made a while ago where I take an amplifier into clipping: http://www.youtube.com/watch?v=zBbOZFC_RUQ  Did it sound similar to that? If so, try turning down the gain on the amplifier and see if it goes away.  BTW, why are you running such an awesome subwoofer with a Bazooka amp?  That setup seems a bit mis-matched.

oops correction its a 10w3v2 not the w6 sorry. its 300 watts RMS. the bazooka amp is 300 watts...and i got the amp for cheap price since i didnt have the money at the time. i tried the sub actually with two different amps and both times it seems like its the enclosure. doesn't sound like the video. sounds like some kind of metal loose in the enclosure. just strange that when i take off the terminal piece that it goes away and when placed back i hear it..thats whats confuisng me..i mean if its the enclousre and if i take off the terminal piece i should still hear the rattling because the sub is still bumping in the enclosure?...i'm gonna go test the ohms...do i just put the leads across the VC terminals? im hoping its not the sub but if its blown its time to get an entire new setup. just seems strange because the sub seems to kick very good when i play it and stuff.

Take out sub and test it free air if it is making the noise,i think its the enclosure...

i hit the enclosure with my hand and hear nothing, with the sub out the enclosure, the sub doesn't make that noise. with it back in it does. the enclosure i inspected seems fine and shook it, pounded it still nothing i hear. might beat the edges or a screw maybe that came loose? not sure. it was a custom made enclosure my friend built so i'm not sure. i'm gonna get a new enclosure and just try that. or i'm gonna borrow a friends enclosure.

OK, so the system makes noise in the car but not on the ground? That makes me think something might have come loose in the car. Possability?This is not a sig. This is a duck. Quack.

no, i took tne enclosure out of the car and put it into another car in my garage and it still makes the noise. BUT when i take the sub out of the enclosure, the vibration or noise goes away. once i slide it back in a little and seal it a bit the rattle is back....i'm guessing enclosure because i dont see or hear anything physically wrong with the sub. i'm gonna get new enclosure tm and see if it does it.

got a new box today n it still rattles BUT i tried adjusting the gain a bit and when turned down it goes away.....so i guess it was clipping?? not sure wat clippind sounded like but it def sounded like a rattle. so does that mean the amp isn't good enough or the sub is done? its the jl 10w3v2 w/ a bazooka 300/1 amp......