dubcnea

i just built a box for my Rockford 12" DVC power sub. it's got approx. 1.2 cubic feet of space and is shaped like a square, but has angles half way down the sides that make the bottom about 5 inches more narrow than the top. anyways, after having glued, screwed, and siliconed the box, then adding carpet...i am still hearing some slight rattles. now i tested it with my home stereo, so maybe that's not fair, but the rattles actually sounded like they were coming from the sub. is that bad? i know it's not blown, but sounds like.....loose stuff rattling. there is nothing in the box, i checked.

any suggestions? oh, and i feel no air coming from anywhere except in front of the sub. the box is sealed, no bandpass.

dubcnea

i guess i'll try to put this on my real amp when i install it and see what happens. unless anyone can suggest anything aside from that?

elduderino

It sounds like a blown woofer, actually.

If you tried it with your home stereo, it was probably getting highs as well, which would not help...

dubcnea

hmmm. well i guess i'll have to try it without that like i said, and see. i turned all but the bass freq. down on the EQ of the stereo to try to cut out as much high sound as possible.

k, tell me if this is possible:

i was in a wreck several weeks ago. i had 4 speakers and 2 subs on 2 diff. amps. it turns out my 6x9s were blown, and i have to try my fronts (4 inchers). but if in fact it is blown subs....could that have come from some type of 'clipping' of the amp due to sudden impact or odd power surge/loss from engine shutting off, etc?? i may have to have these subs checked to see if they are blown. what do you guys think?

elduderino

If your flux capacitor discharged all at once...

No, I don't know of anything like that. Was the HU damaged? More likely a problem with the RCA or the HU...

Back in like 88 Kenwood sold Dow Stereo a bunch of refurb decks. These decks would occasionally send clapmed DC outthe preamp OP. When a Hifonics ap got this signal, the speakers attached to it would make a squaling noise and then some big resistors inside the amp would toast and let out their magic smoke...

DerrickM

Is the DVC a higher-end Rockford product? My cheap "punch stage 1" sub would make an awful vibrating noise when overdriven.

Any chance that your wires are resting against the basket or the box? Maybe the wires are too long and they are rattling?

Does it do it at all volumes, or only at the peak volumes?

dubcnea

the powers that i have are a few years old, but yeah, are the higher end ones. have RMS of 1000 watts and max of 2000. very nice subs. i tried to make sure the wires were short enough to not rest on the basket, but maybe i should take it out and make more certain that it won't hit the basket when the sub is vibrating. if anything, i was under-driving the sub with my stereo, so i didn't play it long. just enough to check for air leak.

this is the first time with the new box, so i'm not sure how it will act with actual amp, diff volumes, etc.


and no, my HU is fine. i had a cap on the amps too, so maybe there was less chance of any type of power surging. and my HU is a bit newer than 88. :P

DerrickM

While you have it out of the box, play it carefully/softly without the box so you can hear the speaker by itself. Should help determine if it's really the speaker rattling.

Also, this sounds silly, but make sure there's nothing metal stuck to the magnet--you know, like an extra nut or washer...

PS - just curious, why did you choose that shape for your box?

dubcnea

i'll do that. i have two...i'll test both. when i played them earlier while in the two-sub box, i don't remember any rattle.

i designed it like that because i have a 96 2.5 TL. i could have just used the box i already had, but i wanted some trunk space. plus i just wanted one sub for now. so i decided to push it back towards the seats. in the trunk there are two angle pieces on each side that slant into the floor of the trunk. that is where the angled part of the box comes in. i wanted to semi-custom design it to sit farther back, giving me more trunk space and more of a custom look. but since i'm a first-timer (for building boxes, etc.) and didn't have ALL the right tools, i may not have gotten exactly what i wanted. but damnit, it's close. maybe if i redo it, i'll make it easier on myself and it'll be better (no angles!).

DerrickM

ResidualFreedom

you did use silicone when building the box didn't you?
I would also reccomend wood glue and "particle board screws" not wood screws... particleboard screws have a larger teeth and they are spread apart a bit more than wood screws. Particle boardscrews will pull them self below the MDF surface when the wood screws will not pull themself belw the surface and will end up spinning freely.

dubcnea

i did use silicone on the inside and outside of the box. i used wood glue and screws. i did use wood screws though, but they all fastened tightly. i'm still semi-confused at the noise.

elduderino

If you are checking for air leaks try using a candle and watchying for the flame puffing... still sounds blown to me.

Or if the hole wasn't round and you screwed it in and tweaked the frame...?

dubcnea

well i didn't have any special tools to make this box. i had a table saw and a jig saw. so the hole may not have been perfect, but it was pretty damn good. i have yet to be able to test it on anything but my home stereo. i still have to check for the wires hitting the basket. like i said, i ran them not too long ago in the other box, and i noticed no noise but bass.