A few quick subwoofer questions

[qoncept]

I have a 12" subwoofer in a box in the trunk that makes a bit of noise. It's not a hum or buzz - it really sounds like a tag somewhere that's just fluttering but I haven't been able to figure it out. I'm hoping, with my limited info, that someone will just jump out and say "oh yeah, that's xxxx, fix it like this." Fingers crossed.

I also just bought another 10" sub and box - the one I just mentioned is going to go in my truck. Do I need to do anything special when I mount the sub in the box, or just grab some screws and go?

Finally... I did add dynamat to the trunk and doors, but I have a few random buzzing pieces. Most should be easy enough to deal with. The window switches are vibrating in the doors, though, and I really have no idea what I can do about that. Any ideas?

[JoeMartin]

For the window switches you'll want to pop them out of their container and put foam/dynamat where it clicks in.
There are 4 little tabs that you have to gently pry away from the holder without breaking them.
What I do is apply very little pressure outward while pulling the switches away from the holder, once one corner pops, I keep pressure and do it to the next one on the same side. Then you just repeat for the other side.

After you have it apart you can take some foam/dynamat/whatever and put it on either side of where the clips enter in to the back piece. Doing so will keep it tight enough that it does not rattle.
I actually need to take my door apart again to fix yet another rattle, if I do, I'll snap a picture.

[toast]

Your fluttering sound is most likely an air leak. How is the box sealed? You can removed the driver and then run a bead of silicone around the edges inside the box. Then put a thin bead around the opening for the driver and screw the driver back in place.

How you mount a box in any automobile depends highly on what is available. Just screwing it to the floor is an option but it is one I use as a last resort. If you do decide to go that route, make sure you know what is on the other side of the panel you are screwing into.

[qoncept]

I'm not sure how the box is sealed. I had someone else install it, but I'll take a look. That definitely makes sense. I'll actually bet the air leak is around the driver itself and not between 2 walls of the box but we'll see.

The box just sits in my trunk while the amp is mounted to the back of the rear seat. I need to be able to take it out quickly for autox which is a much bigger priority to me than bass.

Would it be a good idea to pull the door panel out again and add dynamat to the back side of it (as opposed to the actual door like I already have) ? Seems like it would be but this stuff is still a mystery to me.

[toast]

Not sure what you mean by 'Dynamat'. In general people use that term to refer to Contrained Layer Damping sheets which are usually a sticky butyl rubber bonded to an aluminum layer. That is good for a panel which can vibrate a lot and act as a speaker, but for the back of interior trim panels (such as your door panel) I recommend covering it in Ensolite or some other close cell foam. Weighs basically nothing and does a great job absorbing sound energy that is in the air before it actually gets to your door panel.

Even if you don't autocross with the sub box, street driving can (hopefully be full of fast turns as well so you should somehow mount your box to the car. You can bolt an angle bracket on the side of the box and then mount a bolt into the seat back with the thread sticking out. Connect the angle bracket to those threads using a wingnut. Easy on, easy off and still does a solid mounting job.

[qoncept]

I've been driving with the sub box unmounted for over a year without any issue so I'm not worried about that. It kind of tucks under the rear deck with just a bit of room to spare so it's not going anywhere, and I drive like a granny on the street anyway (38mpg).

I just bought ordered some closed cell foam sheets and have next week off. Should be able to get the noises dealt with. Thanks!

[onefitz]

Originally Posted by toast

You can removed the driver and then run a bead of silicone around the edges inside the box. Then put a thin bead around the opening for the driver and screw the driver back in place.

I'd be careful with putting a driver on/in a box with uncured silicone. The fumes can deteriorate foam surrounds. It also makes removing the driver a pain. I just use foam tape. Does the same thing without the mess.

[JoeMartin]

Qoncept, I'll admit that I'm rather new to using Dynamat/other materials...
But what I have learned is that it can make a Hell of a difference. For the door panels, I would recommend picking up some All Purpose foam weather stripping for any place that plastic contacts other plastic.
I use this stuff from PepBoys:
http://www.pepboys.com/product/details/8977177/00071
(That's not the EXACT one, but it's the foam self adhesive weather stripping)

That stuff did wonders for making my door panels actually quiet and sound good with the 6.5s in there.

If you want a full walk through on REALLY doing some dampening though, there is an amazing post from these forums:
http://www.ft86club.com/forums/showthread.php?t=28506

[qoncept]

I'll take a look at that, thanks for the link. We got a few inches of snow this weekend so the car is officially hibernating till spring and I won't miss it if it's torn apart for days/months.

[babydriver]

Originally Posted by toast

Not sure what you mean by 'Dynamat'. In general people use that term to refer to Contrained Layer Damping sheets which are usually a sticky butyl rubber bonded to an aluminum layer.

Dynamat is a commercial brand of the constrained layer damping sheet that you're describing. Any Best Buy will have it in fairly large sheets for sale in the auto sound department.

Regarding the fluttering noise, I agree that it is probably a leak in the box or in the speaker mount, but if the speaker box happens to be ported then you could be hearing port noise. Then you would have a Port Noise Complaint.

[qoncept]

Originally Posted by babydriver

Then you would have a Port Noise Complaint.

I'm not one to spam a million smilies but