Fiberglass VS. Wooden Sub Boxes

[SliceTheRice]

I know most people use fiberglass for visual benefits but how does the sound differ from wood? I'm looking to get a box and I really don't give a crap what it looks like, just how it sounds. Does one sound better than the other?

Also I've noticed some sub boxes seal the subs independently from each other. Is there a benefit/con to that?

Thanks for the help...

[jsavi85]

honestly, it all depends on the sub. Each sub comes with a user manual and in the manual it says the type of box the manufacture recomends for best sound quality.

[SliceTheRice]

What would you say is most common?

[shawngtp]

Send me your bumper son!!!

[SliceTheRice]

[papaspanky]

MDF (medium density fiberboard) is by far the most common material used to build sub boxes. (if a box is made of wood/particle board it will not last long) and will always be less expensive than fiberglass. as for a difference in sound if the box has the right dimensions for the sub installed in it and is correctly assembeled the human ear will never detect the difference.actually most fiberglass boxes are built around an mdf frame. as for the subs being separated in the same box it is mostly done to keep the resonances from the speakers separated because no two speakers are exactly the same.it will be a lot easier to tell if you have a problem with one of the speakers.

[1LoudGrandPrix]

mines made of mdf and it just has resin inside... thats only to make the most out of every watt(for comps)

[matt5112]

You want the most rigid box possible.

Just happens that building it out of MDF and re-enforcing it with MDF bracing makes it strong.

Heres an example of what I call well re-enforced:



That sub is a beast... LMS 5400 18... Only multiples.

[I800C0LLECT]

sometimes...I really don't want to know the face behind the name

[gtpinsc]

i dont think thats matt lol

[matt5112]

No that really isnt me.

That guy IS insane though:

[IMG][/IMG]

Heres another picture without that guy in it lol:

[Carpepoon]

Lets just put it this way since I've built dozens of both. If you don't know what your doing in fiberglass don't waste your time. You have to know how to properly mix, size, frame, wrap, bondo, sand, paint etc... I used fiberglass for clients wanting to put subs in odd places. If your just starting out and don't care what a box looks like dont waste your time!! The thing to remember is the box is what makes the sub. If your box is flimsy or not built to spec (internal volume, port size/length etc) your sub is not going to be at its potential.
Building a rigid fiberglass enclosure is not easy to do. And measuring its internal volume is even harder. Building a box out of MDF and calculating its internal volume to match the specs is very easy to do. Just make sure its at least 3/4" MDF. Originally I started by fiberglassing the inside of my boxes but since I used to compete with small sealed enclosures it didn't make much of a difference. So from then on I just sealed everything with liquid nails as I built and then coated the inside with spray on bedliner.

[matt5112]

You could use some nice oak instead... Even more rigid.

If you just use carpenters glue then line all the corners with silicone its guaranteed to be sealed.

Just dont put in the woofer till the silicone has cured. The fumes apparently eat foam surrounds.

[MrTube]

Yanno I could be wrong but I swear that looks like plywood and not MDF.

MDF (which is in the particle board category) works best because it is most dense. Wood would last just as long it simply produces more noise and a cabinet\enclosure should not produce noise.

Some of the best enclosures I have seen where made from either 1" thick MDF or concrete.

The concrete ones were not in a car...... I wouldn't recommend it.

[matt5112]

Plywood works just as well, its lighter and more expensive though.

Typically only used by guys with deep pockets in home audio since they can afford it and like the one side veneer stuff so they dont have to do that themselves.

Just assemble, stain, enjoy.

[MrTube]

Matt: plywood was commonly used in the 50s and early 60s.. companies switched to MDF because it was denser. a 1/2" thick MDF box will produce less noise then an equally built 1/2" plywood box.

This is why you never see plywood cabinets on ANY house speakers, especially expensive ones. I assure you they can afford plywood on a pair of $5-30K speakers. They all use MDF or HDF board.

I'm not sure where you have seen quality home enclosures made from plywood. Have articles? Only cabinets I know made from plywood are commercial\PA cabinets. And its because they are durable when it comes to abuse. Not sound quality.

[matt5112]

Density is not what you're after, its rigidity.

More resistance to flexing the less colouration you will get from the box.

I used to be on AVSforum.com but they're all pretty insane over there.

Its either overkill with the subs and no speakers that can keep up with them or waste of time sub builds.

Hardly ever does anyone build their own speakers from scratch anymore. They just use someone elses design, have a cabinet maker build the box for them and they install the drivers and wire it up.

Wheres the fun in that?

[Carpepoon]

Density is not what you're after, its rigidity.

Actually you want both.

[matt5112]

Yeah that makes sense.

But the most common issue is rigidity.

If it vibrates, then who cares how dense it is?

[Carpepoon]

Yeah that makes sense.

But the most common issue is rigidity.

If it vibrates, then who cares how dense it is?

I think you just answered your own question....kinda.. If its not rigid it will flex. But if its not dense, sound can pass through it very easily. MDF is both dense and rigid (and cheap) which is why its usually the material of choice.