Dynamat on the inside of a subwoofer enclosure... good idea or not?
08-08-2003, 06:35 PM
#11
AudiWorld Super User
Thread Starter
Join Date: Oct 2000
Posts: 10,540
Likes: 0
Received 0 Likes
on
0 Posts
It is an MTX Thunder502 Bridged 4 Ohm Load 360
So I need to seal the bottom completly then? How much space is allowed- ie for cables, etc? I am sure I can build a bottom for the sub area. The Sub is working for sure, I mean it is pounding- visiably, as well as I can feel it. I will silicone all the edges. How much does the size really matter- I mean if it is 1 cubic foot vs .6 or 1.1? As long as it is sealed it should be OK correct? Also if I install a port- what diameter and low long should it be?
08-08-2003, 06:41 PM
#13
AudiWorld Super User
Join Date: Feb 2001
Posts: 6,720
Likes: 0
Received 0 Likes
on
0 Posts
I would advise against even trying to port it. Try it sealed. 1st though, try
to estimate the internal volume you're working with. It affects the response curve/performance of the speaker. If you're 10% off either way you'd never know, but you gotta seal it off.
How close to the metal is your MDF? If it's close enough to silicone it, then go for it. You'll just have a crappy time removing it someday. Make sure that the silcone fully cures (2-3 days) before you mount the sub, or the fumes will weaken the rubber surrounds of the sub.
How close to the metal is your MDF? If it's close enough to silicone it, then go for it. You'll just have a crappy time removing it someday. Make sure that the silcone fully cures (2-3 days) before you mount the sub, or the fumes will weaken the rubber surrounds of the sub.
08-08-2003, 06:48 PM
#15
AudiWorld Super User
Thread Starter
Join Date: Oct 2000
Posts: 10,540
Likes: 0
Received 0 Likes
on
0 Posts
actually I will cut a piece of MDF and screw it to the bottom...
above the cables and the floor. My question is about cabling- obviously the speaker cable has to come though, as well as there is a bolt that comes though to secure the box down. What should I do about these cuts I will have to make? Do I just make a mess with silicone and really seal it all up? I plan to silicone ALL of the corners and edges, to make sure it is really sealed- everywhere except the top, so it can be removed at some point. Thoughts?
08-08-2003, 07:02 PM
#16
AudiWorld Super User
Join Date: Feb 2001
Posts: 6,720
Likes: 0
Received 0 Likes
on
0 Posts
Yes, just dab enough silicone around the openings for a good seal. Let
the stuff cure adequately!
To seal the sub to the MDF, I like to use rope caulk (aka cord weatherstripping). It's a sticky clay-like material available at any hardware store/Home Depot:
<img src="http://www.exelaris.com/ttaudio/cord_weatherstrip_front.jpg">
I also think you should consider packing the enclosure with polyfill as I've done here . . .<ul><li><a href="http://www.exelaris.com/ttaudio/TT_Audio_Subwoofer.html">TT Audio Subwoofer page</a></li></ul>
To seal the sub to the MDF, I like to use rope caulk (aka cord weatherstripping). It's a sticky clay-like material available at any hardware store/Home Depot:
<img src="http://www.exelaris.com/ttaudio/cord_weatherstrip_front.jpg">
I also think you should consider packing the enclosure with polyfill as I've done here . . .<ul><li><a href="http://www.exelaris.com/ttaudio/TT_Audio_Subwoofer.html">TT Audio Subwoofer page</a></li></ul>
08-08-2003, 07:11 PM
#17
AudiWorld Super User
Thread Starter
Join Date: Oct 2000
Posts: 10,540
Likes: 0
Received 0 Likes
on
0 Posts
The sub came with a foam material I used around it...
on the inside lip, I screwed behind that. I am just wondering your thoughts for some real small (mm sized) holes, as in, if there is something that just allows a very very small amount of air in. Also what are your thoughts on if I actually blew the sub? Cause if I did I do not want to mount the sub. I literally had it installed for about 1 day- used it for maybe 45 min total- diffrent volumes- nothing TOO crazy. Also your thoughts still on the Dynamat?
08-08-2003, 08:32 PM
#18
AudiWorld Super User
Join Date: Feb 2001
Posts: 6,720
Likes: 0
Received 0 Likes
on
0 Posts
Re: The sub came with a foam material I used around it...
Q--I am just wondering your thoughts for some real small (mm sized) holes, as in, if there is something that just allows a very very small amount of air in.
A--Just plug them all w/silicone & you'll be fine. Air leaks can make noise in & of themselves, plus they monkey with the suspension of the speaker provided by the sealed cushion of air.
Q--Also what are your thoughts on if I actually blew the sub? Cause if I did I do not want to mount the sub.
A--If it's blown, you'll want it sealed for next time! Seal it and give it a listen. I still hope you'll try to get an idea of the volume of the enclosure. Different brands/models perform better in different size enclosures.
Q--Also your thoughts still on the Dynamat
A--It won't hurt anything, but if everything else is done right you'd be hard-pressed to know the difference. That said, the gas tank sits under the rear seats, and it's loud as hell without the seats covering them (as my car's been for months now). It's probably nice to isolate the cabin.
A--Just plug them all w/silicone & you'll be fine. Air leaks can make noise in & of themselves, plus they monkey with the suspension of the speaker provided by the sealed cushion of air.
Q--Also what are your thoughts on if I actually blew the sub? Cause if I did I do not want to mount the sub.
A--If it's blown, you'll want it sealed for next time! Seal it and give it a listen. I still hope you'll try to get an idea of the volume of the enclosure. Different brands/models perform better in different size enclosures.
Q--Also your thoughts still on the Dynamat
A--It won't hurt anything, but if everything else is done right you'd be hard-pressed to know the difference. That said, the gas tank sits under the rear seats, and it's loud as hell without the seats covering them (as my car's been for months now). It's probably nice to isolate the cabin.
08-10-2003, 04:13 AM
#20
AudiWorld Super User
Join Date: Oct 2001
Posts: 4,734
Likes: 0
Received 0 Likes
on
0 Posts
dynamat will eliminate any type of vibration.
Sub frequencies will tend/need to bounce around to complete a sound. You have thus eliminated this by lining your enclosure with dynamat.