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My sub box has the carpet wrapped over the baffle. I removed the original sub and am now installing it with a new sub.. After looking at the enclosure carpet it's really matted down tight where the sub was mounted. Is this a decent gasket material now? Or should I still run some foam gasket tape on the driver mounting flange.

Do you usually run with a bare wood baffle surface or install a driver over carpet?
 

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I have my subs mounted over the carpet. Doesn't seem to be leaking either.
What he said. No problems.

If anything, you *need* a very small leak in a sealed box.
 

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foam rolls are cheap and readily available in a variety of sizes and thicknesses at lowes/home depot. i use them.
 

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for foam? not really a factor here since it will be compressed as much as possible under the weight of the sub. just get any window/door foam roll and go to town.
 

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I have never had any issues with a leak, caused by carpet.

FWIW I had a guy complain about a leaky sub(after an spl run), claiming it was because that i had mounted his sub drivers, over the carpeted box. Turned out one of his subs' cone had started to separate from the surround.
 

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^sarcasm? Dont really understand how you could increase output by 10db on a leaky sealed box.

As far as addressing the original topic, Carpet has worked completely fine for me. When a gasket is used around the frame / flange of the sub.

On some home audio drivers without a gasket (peerless) i use 1/4" foam tape from parts express
 

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The leak will allow the sub to be centered at rest, allow for temp/pressure variations, is a typical thing to do when building home speakers. Most boxes leak anyway. The issue is long as the leak is not enough to pass air in use, and make a noise or change the response of the sub.

Never had a problem with carpet sealing subs, long as the sub fits flat and all that as the carpet can sometimes make it hard to see if the hole is a fuzz too small or something.

If you use foam get open cell that you can flatten out, its usually gray in color and cheap. You can bend the rim of a basket if you crank the screws down one at a time into thick foam or closed cell, be careful of that with stamped basket subs. I only use foam on bare surfaces and usually put it on the sub. Since I use it for other stuff I like to buy a big roll of topper foam and cut to size I want. Even that is pretty thick for a sub and its only 3/16 or something but fairly thick foam. It seals baffles to cars really well.
 

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For what purpose? :confused:
See below.

The leak will allow the sub to be centered at rest, allow for temp/pressure variations, is a typical thing to do when building home speakers. Most boxes leak anyway. The issue is long as the leak is not enough to pass air in use, and make a noise or change the response of the sub.

Never had a problem with carpet sealing subs, long as the sub fits flat and all that as the carpet can sometimes make it hard to see if the hole is a fuzz too small or something.

If you use foam get open cell that you can flatten out, its usually gray in color and cheap. You can bend the rim of a basket if you crank the screws down one at a time into thick foam or closed cell, be careful of that with stamped basket subs. I only use foam on bare surfaces and usually put it on the sub. Since I use it for other stuff I like to buy a big roll of topper foam and cut to size I want. Even that is pretty thick for a sub and its only 3/16 or something but fairly thick foam. It seals baffles to cars really well.
Precisely what I was about to say. It should be a bit difficult to push the sub down, and if you get it down far enough and hold it there for a second, releasing it should cause it to rise very slowly.

Think about it guys, seriously. What happens if you have a 100% perfect sealing box and you build it at night on a 60 degree temperature and tomorrow is a hot 100 degree day? The air inside the box expands and the sub is stuck at its maximum excursion in one direction. What happens if you run the sub at high levels for a while and the heat of the voice coil increases the temperature of the air in the box?

Same thing if you build it at sea level and go for a ski trip in the mountains. You need to have some way to account for fluctuations in temperature and atmospheric pressure, so building a perfectly sealing box is IMO stupid unless you have a temperature and pressure controlled trunk.
 

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HOT DAMN!!! I'm gonna make a killing on my new "patented nitrogen filled sealed subwoofer enclosures.

For an extra charge, you can get the premium "helium" filled model. It will come with mounting feet and bolts so you can bolt it to the frame of the vehicle and reduce weight due the lifting effect of helium.
 

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^^^^^^^^^^^^^^^ :eek:

U r nominated for the 2011 Nobel Prize. Now for my part: please do NOT make a hydrogen filled box. Excessive compression may cause combustion. C? I r smart 2!
 

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Here's the serious answer.

If you have a 1 cuft sealed enclosure, and increase the internal temperature from say 70*F to about 100*F you'll get a 5.75% increase in volume. This will take a 1 cuft enclosure to 1.0575 cubes. HARDLY enough to push the cone to it's mechanical limits.

I'll let the geniuses here figure out how much of a difference in Qtc that makes. Sure as hell no more than venting your enclosure with a drill.
 

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HOT DAMN!!! I'm gonna make a killing on my new "patented nitrogen filled sealed subwoofer enclosures.

For an extra charge, you can get the premium "helium" filled model. It will come with mounting feet and bolts so you can bolt it to the frame of the vehicle and reduce weight due the lifting effect of helium.
Let's fill it with liquid helium. I can go to my old test site and get some. But it'll off gas quickly so we'll need a steady supply. **** ain't cheap, y0.
 

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Let's fill it with liquid helium. I can go to my old test site and get some. But it'll off gas quickly so we'll need a steady supply. **** ain't cheap, y0.
Hey, I can source liquid helium. I can also get a coldhead and compressor to run the thing. All we need is a chamber under near perfect vacuum. At which point, I would have to say, with absolute certainty, that carpeting as a gasket would be insufficient.

Chamber would be a good 4-5 Kelvin. Your voice coil ain't heating up in that ****.

Hmmm, you'd need two chambers. One for the liquid helium. It would boil off at about 5 kelvin, pressurize the vessel, then have a 5.25 psi valve (which I can get) release the super cold gas into a coil within the enclosure space to draw out the heat, then cycle it back into the liquid helium vessel. I GUARANTEE your voice coil ain't getting hot when you have a temperature delta of 268* kelvin between ambient and your refrigerant.

I don't know though. Liability would be tough, as I don't know if you've ever been around liquid helium when it flashes to gas. It'll **** you up. You're better off putting your face in a bonfire. Instant frostbite, then asphyxiation. I like liquid nitrogen. It can actually maintain liquid state in atmosphere long enough to pour some into a plastic soda bottle, cap it and throw it in a dumpster. The explosion is loud when it finally flashes. Helium flashes instantly. It's no fun, but at least it rises when it flashes. Nitrogen pools, so when you pass out when the nitrogen displaces the air in your lungs, you fall to the floor where the rest of the nitrogen gas has pooled. We've actually lost engineers because of that, as in dead engineers.

Or we could just shove an air conditioner in our enclosure.
 

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nothing like a substance so cold it burns. ;)

I prefer helium over nitrogen. Makes the box lighter since it's less dense. and since the density is lower, it's more like a free air atmosphere. Now I can use a box that is more IB than small and sealed. Awesome. From there on, my 10ft^3 box I use in winISD is more accurate even if the geometry is (enter ratio of atmosphere vs helium here). Sweetness!

Ive got extensive training with cryogenics. No liability there.

Oh, and let's not forget saving some for the wiring. Superconductor FTW!
 
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