Sub sounds like its rattling or burping? (Video)

[audiobaun 5,000+ posts]

Last time I talked to bob at american bass he said 2.5 and tuned to 36hz was ideal I tried haha. I have it wired negative to negative terminal then to the negative port on my amp same for positive if I'm correct this is 4ohm to 2ohm

that is correct for a dvc4ohm sub/single to 2ohms...wired correct there

 

[audiobaun 5,000+ posts]

Here's a little information that I forgot to include my subs left side negative terminal broke off. I ha to solder the thin silver fiber like wiring that connect the sub to the + and - terminals to a gold connection that I got from a subwoofer parts store online I had no problems with this and was able to repair the broken terminal fairly easily so I didn't really think of that. Could this be the problem?

check see if it broke off.what do you mean gold connection?one solid gold connection that both terminals are soldered too? pull that sub out, and take couple picks of the soldering repair.that could be your issue.lets have a look?

 

[audiobaun 5,000+ posts]

by way you explained it,sounds to me like you have basicly soldered the + and - connections to the same post basicly...doesnt sound right

 

[audiobaun 5,000+ posts]

that could be the reason your sub is hitting out of phase,..reason why i was thinking your wiring configuration isnt correct..you can try to run /check that sub in a 4ohm load to see if that terminal is the issue, by just hooking up one side of the sub,just as if it were a single voice coil sub.+ to +, and - to - on one side of the sub,and then try other side of the sub that you repaired.be sure turn your gain. down pretty low to do this If you do the/test the repaired side, and and not correctly repaired right.it should go into protect mode on the amp quickly.how i test a blown sub..one coil gets blown, and i still run the other side as a svc sub in 4ohms..never had an issue doing that/didnt have money to replace the sub,so i just had run in 4ohms till i got money for another sub.you are only testing this way,and if your repair isnt done right, then you can try to repair it again,or just run it on the working coil side @4ohms@ 1/2 the rms value of the sub

 

[REDz28 10+ year member]

Hey no I just fixed the negative terminal it was one of those gold posts i don't know the correct name but I just fixed the negative side I didn't wire them togther or anything. I then went - to -, + to +... Ill get pics for you tomorrow. On thing I want to try is taking the sub out and playing open air if I don't hear that noise then I'm assuming it's the box. I'll also try your suggestion and post results. How would I go about fixing open space around the rubber seal that comes on contact with the MDF? That's if there is any but just to be sure. And I'll try and go get a DMM as well but I really think I might have just messed the box.

 

[Imtjnotu 5,000+ posts]

iim thinking its an air leak somewhere....

 

[audiobaun 5,000+ posts]

Hey no I just fixed the negative terminal it was one of those gold posts i don't know the correct name but I just fixed the negative side I didn't wire them togther or anything. I then went - to -, + to +... Ill get pics for you tomorrow. On thing I want to try is taking the sub out and playing open air if I don't hear that noise then I'm assuming it's the box. I'll also try your suggestion and post results. How would I go about fixing open space around the rubber seal that comes on contact with the MDF? That's if there is any but just to be sure. And I'll try and go get a DMM as well but I really think I might have just messed the box.

what do you mean about the open space around the rubber seal? it should be flush, and it should not leak any air around that sub as i stated earlier,if it does,your cut out is too big for the sub?? your sub should fit tightly in your cut out,with maybe a 3/32 bigger to 1/8 in at the most..cut out needs be inside diameter of the mounting holes??no bigger,or you will have a gap/air leak around the sub ring/basket.What is the sub you have? brand,and model #? maybe i can look/find specs for the sub/google up

 

[audiobaun 5,000+ posts]

iim thinking its an air leak somewhere....

i think you may be correct...was one of my first assumptions,other than wired out of phase

 

[REDz28 10+ year member]

Well that was hypothetical I thought maybe that might be an issue its pretty sealed up around the rubber to mdf. And i had a problem mounting it the first time the hole was to small so I trimmed it up a bit to where I could slide by sub right into place. So now the question is let's say that is also a problem how would I about fixing that? And would the air leak be around the sub or could it possibly be somewhere around the seals?

 

[mylows10 5,000+ posts]

Yes check all seals. You can use silicone to reseal if needed

 

[audiobaun 5,000+ posts]

easiest way for me to fix that..not being a custom box as you have, and i generally have myself..is to make a new baffell/face,and recut the hole without rebuilding the entire box, and make sure you have siliconed the inside of the sub box, and outside to make sure its air tight just the port will be exposed.

 

[REDz28 10+ year member]

Ok I'll try resealing it as well. And I used wood glue and actually tried taking the box apart today. It wasnt havin it haha the glue made it next to impossible to remove a single side.

 

[audiobaun 5,000+ posts]

well be sure to get a tube of caulking/silicone from home depot/or? and go over every corner inside and out..its worth the $3-5 for the caulk/silicone

 

[goingdef 10+ year member]

instead of guessing why not just pull the sub and free air it on a test tone "real low obviously" and see if it's the sub, I find around 32hz will allow you to hear any mechanical noises I have used this on a couple of occasions to find spiders that had started to pull loose, just start at 0 on your HU and turn it up slow you will know in a few minutes whats wrong and to ensure your getting + - correct use a small battery c or d cell and note what direction the woofer jumps and make sure both sides react the same.

 

[REDz28 10+ year member]

Yea I planned on free airing it tomorrow to lots of testing to do!