sealed boxes

[nuce308]

i have two alpine type-s 12" subs and a m350 amp and i build my own box out of 3/4 plywood but there are still small spaces where the different panles meet, the spaces are very small, 1/8" at the largest. my question is will these spaces make a difference in the sound quality and if so what would eb the best way to seal them. and my second question is should i line the box is dynamat or an equal product. people have told me to do this but i figured the guys on here would know better. thanks in advance.
tommy

 

[xcessive50]

well , idealy,particle board or MDF should be used instead of plywood,but i guess plywood could work too. go to home depot and look at MDF in 3/4". This is the ****zle when it comes to making boxes. After that , go to the section that has all the sealants, like caulking and stuff and pick out one that stays pliable when dry (rubbery) that fits in a caulking gun (prolly need more than one tube) (i like that outdoor 50 year warranty stuff ) and completely seal up any cracks or holes like you were making it waterproof.(you should actually run a bead on the edges before assembling the box) You could also go to a stereo store that sells prefab boxes to see how they did it.

Oh , yes it will make a big difference and no you do not have to put anything inside the box.

 

[nuce308]

we did use a sealent when we put it together but it didnt seem to work so well and i said it wrong it wasnt plywood it was mdf.
thanks for your help.

 

[BBrinks]

Don't use plywood when you make a sub box. MDF like he said is much better to use. When you build it, use a lot of wood glue when you screw it together. After it's dried, use silicone along every inside edge, using your fingers to press it into the crack, just to make sure it's completely sealed. It'll make a huge difference if it's sealed properly. It'll smell for a bit while it's curing, so you might want to leave it alone for a good day or so. Don't even bother lining it with sound deadener. You can line the inside of the box with some polyfil, but using a deadener will do absolutely nothing.

 

[chrisbudl1]

It's been years ago, but on a box that I made, the angles didn't line up right, so I used a fiberglass kit from walmart to fill in the seam. Hopefully caulking will work for you. just thought to throw that idea out.

 

[Bloomy316]

i have two alpine type-s 12" subs and a m350 amp and i build my own box out of 3/4 plywood but there are still small spaces where the different panles meet, the spaces are very small, 1/8" at the largest. my question is will these spaces make a difference in the sound quality and if so what would eb the best way to seal them. and my second question is should i line the box is dynamat or an equal product. people have told me to do this but i figured the guys on here would know better. thanks in advance.
tommy

If you are describing open gaps where your panels come together, you definitely have a problem. You may as well have $29 subs in there because your Alpines are not working anywhere near their optimum. Are the panels not cut squarely? I think I would regroup and build another box. You can try to fill the gaps, but it will never be ideal. Just my opinion.

 

[Nottoofast50]

Dude get some liquid nails... best stuff for sealing boxes.

 

[JokerWylde]

Like chrisbud said above, fiberglass works well to seal up edges and stuff, assuming you know how to work with the stuff (not a difficult thing for this type of project). You could even put a layer all over the inside, flat panels as well as the edges, just to make sure it's all sealed up well.

Also, I'm not sure what kind of surrounds your speakers have, but if you do use silicone to seal up the edges, you might want to let it cure overnight before you stick the subs in. Some surrounds can be adversely affected by the fumes that curing silicone gives off.

 

[nuce308]

thanx for all the replies, whats polyfil though? i think the fiberglass might be my best bet cause i know how to work with it. also what is liquid nails? one last stupid question (sorry for so many) but whats the best type of fastener to mounts the subs and amp to the box...woods screws or should i use bolts? and i plan on covering it in automotive carpet but do i ahve any other option besides that?
thanks alot

 

[Nottoofast50]

Liquid nails is a calk like substance they sell at home depot loews etc. It is made for gluing wood furniture. It sets up fast(30 mins) and drys like caulk.

 

[nuce308]

so if i put something like that around all the places where panels meet will that seal it well or should i still use fiberglass?

 

[BBrinks]

Use both. When you fasten the panels together, use the liquid nails between the pieces. Then use the fiberglass along all the interior cracks, or just put down a layer or two down on all the sides.

 

[nuce308]

sounds good im going to wal mart now
thanks alot you guys for all the help.

 

[xsivpwr]

Dont use silicone caulk.... silicone fumes will eat away at the rubber surrounds of your subs...


Liquid nails is the **** for sub boxes... glue it and screw it together... its strong enough that you could remove all the screws once its dry and itll still hold together

 

[BBrinks]

Silicone's fine to use, as long as you let it cure for 24 hours before you drop in the sub. The only harmful fumes it produces are when it's curing.

 

[JokerWylde]

And as for your question about finishing options, you can do just about anything you want, really. It mostly depends on how much prep work you're willing to do. Carpet is pretty good at hiding imperfections, so you don't have to have a pristine surface beforehand. You can also cover it with vinyl, although imperfections tend to show up a lot more if you do this. You need a pretty smooth surface to glue the vinyl to. Another option is to paint the box, but you obviously need just about a perfectly smooth finish beforehand if you want to do it.

 

[nuce308]

well i got a fiberglass kit today and dumbass me didnt read it completely at the store and it didnt come with the clothe i need. what kind of clothe do i need and is there any other kinds i can use for it? by the way wal mart didnt have this kit.

 

[JokerWylde]

You should be able to get Fiberglass cloth or mat at Autozone or a similar store in their body work area. Brand doesn't really matter. I think I'd use cloth for this though, since the mat makes a much bigger mess. It usually comes in a plastic bag package that has 8 or 9 sq feet, if I remember correctly. About 3 bucks or so? Seems like what I've used the most is the Bondo brand stuff, since that's what most local stores carry.