97 JBL subwoofer vibrations

[Zorro]

i just got my mtx's installed with my 1000 watt amp but when i turn the bass up i get this horrible sound. so i checked it out and its coming from the little JBL subwoofer that came with my Eddie Bauer. Im thinking the sub cover is the problem that's vibrating so im guessing i should just take it off. How do u get it off and is that alright to leave it without a cover?

 

[SiLenZe]

its fine without a cover. i have no cover on my stealth enclosure. and took it off on my stock one.
if you can take it out and make sure its still sealed. tighten all the screws in the front. there is one screw on the back that goes right into the middle of the sub. it has a ruber thing around it sealing it. check to make sure thats still ok.