Weird knocking sound - I'm a totally clueless

[mclerico83 5,000+ posts]

my old prefab for under my seats make that exact noise.. the wood split where the top and left side med and slapped.

yea i put a pre fab ram box in someones truck and the whole thing made a vibrating noise like a sub was bottoming out, put it in a custom enclosure all gone //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[edavis.j 10+ year member]

here's the sound again...sorry for the 2nd song lol trying to get some different kinds of bass in there so you can hear the sound...

 

[xxxbasshead 10+ year member]

gonna agree that it is the box i built a box for 2 12s and where i had the a bolt holding it to the trunk flor cracked a little and air was leaking as soon as i sealed it up it soundd good as new

 

[edavis.j 10+ year member]

In the free air video does the sub sound alright and does that scratchy sound when I push on the left side sound alright?

 

[Apollo220 10+ year member]

when the sub was out did you check the box to see if it been cracked or maybe coming apart like they said earlier ?? cause free air sounded better than in the in the box to me

 

[edavis.j 10+ year member]

Well I'm not a box expert so I don't know how it should look, but in general, imo the box looked shitty...and the one thing I never liked about the sub is the dustcap...here are pictures of the dustcap and of the inside of the box...can't really see much...but I'm hoping someone can tell from those videos if the sub is ok?

edit: lol gotta fix pics

edit: pics of box + dust cap

 

[Apollo220 10+ year member]

just push on the inside of the box and listen if you hear an crackling noise like it loose or cracked

 

[Apollo220 10+ year member]

i mean shoot the sub could even be to deep for the box and it might be hitting the back of the box when it playing have you measured the depth of the box compared to the sub ??/

 

[edavis.j 10+ year member]

Well this problem just started recently...didn't have a problem with that noise at first so I don't think mounting depth is a problem, but I'll measure now.

Also updated with pics, see my above post...

edit: sub is 9" deep from where screws mount, box is 12" deep from where the screws mount. and like i said, never had a problem before.

 

[edavis.j 10+ year member]

anyone have more input with the updated videos/pics?

 

[Apollo220 10+ year member]

hmm it must be a problem with the sub internally then its hard to tell what the noise is off the mic on the video.what i would do is wait till u get your new box . see if that stops it and then if it still continues then send the sub in for repair . it still under warranty so they will fix it for free

 

[DidUHearThat? 10+ year member]

My first thought is you are having a power problem. Not the subwoofer itself. If you're getting popping and not correctly powering on that sounds like a wiring or electrical issue, not mechanical. That power wire doesn't look secure. Use some zip ties with screw anchors to get that cable out of the way and trim it to length. Pull and reseat your remote and audio connections. Look for cracked or broken wires, or small loose strands of copper shorting the terminals. Tighten everything, including the amp mounts and speaker wire connections.

Also check the connections behind the HU, battery and fuse connections. Tighten and zip tie down everything secure, tight and out of the way. No loose floppy wires.

 

[Apollo220 10+ year member]

My first thought is you are having a power problem. Not the subwoofer itself. If you're getting popping and not correctly powering on that sounds like a wiring or electrical issue, not mechanical. That power wire doesn't look secure. Use some zip ties with screw anchors to get that cable out of the way and trim it to length. Pull and reseat your remote and audio connections. Look for cracked or broken wires, or small loose strands of copper shorting the terminals. Tighten everything, including the amp mounts and speaker wire connections.
Also check the connections behind the HU, battery and fuse connections. Tighten and zip tie down everything secure, tight and out of the way. No loose floppy wires.

i was thinking a power issue to with it cutting off . but idk it could be some many different issues

 

[edavis.j 10+ year member]

My first thought is you are having a power problem. Not the subwoofer itself. If you're getting popping and not correctly powering on that sounds like a wiring or electrical issue, not mechanical. That power wire doesn't look secure. Use some zip ties with screw anchors to get that cable out of the way and trim it to length. Pull and reseat your remote and audio connections. Look for cracked or broken wires, or small loose strands of copper shorting the terminals. Tighten everything, including the amp mounts and speaker wire connections.
Also check the connections behind the HU, battery and fuse connections. Tighten and zip tie down everything secure, tight and out of the way. No loose floppy wires.

I can't trim/cut the wires to proper length yet because I don't know where exactly I'm going to mount my amp/cap yet, until I get my new box. I went through and checked all my wire connections and everything is great now. I tracked down the reason why my amp won't power on and I don't understand why. But every now and then the voltage on the remote wire drops down...I checked the voltage and it was bouncing between 4-8v, and the amp wouldn't power on, I came back 5 minutes later and it was reading 13v. I'll have to figure out which fuse it's hooked into, a shop originally installed the original wiring.

The thing is though, the system worked great for 2-3 weeks, and then this randomly started happening. Never had a problem powering on, never had any problems with the subwoofer.

I really need to get my new box so I can see if it's the box or not. I pushed on the bottom of the box and it sounded like it cracked a little, but I don't know. I was just hoping someone could tell from the sound of free air'ing it if it sounded alright or not.

 

[audioholic 5,000+ posts]

i mean shoot the sub could even be to deep for the box and it might be hitting the back of the box when it playing have you measured the depth of the box compared to the sub ??/

I cant even imagine how you think its possible the sub is making contact with the back of his box when playing.