[spyderx]

I just finished my sub box for a pair of 10" Alpine type-R's, made from 3/4" MDF w/1 cf volume each. It does the job but I've founded them a little boomy cuz I was really looking for tighter sq sound. By the way, I'm driving it JL p1200.1 but have yet to tune it.

The real problem is that it's too damn heavy! Must weigh around more than 80lbs! I have it sitting on my rear seats but I can really feel how it's putting a drag on my car's suspension and acceleration.

Is there a lighter solution to building a sub-box? I'm not looking for world conquering hyper-bass, just enough of tight solid bass w/ decent sq. Should I look into tube housings or different wood material?

thanks.

 

[mytalon]

Take out your backseats

 

[TechT]

http://www.mmxpress.com/element_enclosures.htm

Or

Make a sub-box using Fiber Glass and MDF.

 

[spyderx]

Take out your backseats

My spyder's back seat padding weights less than 10lbs. Taking the whole back of the seating would be too much pain! So let's rule that out!

 

[spyderx]

http://www.mmxpress.com/element_enclosures.htm

Or

Make a sub-box using Fiber Glass and MDF.

That's nice but expensive! You think I could use plastic tubes like the Bazooka housings?

 

[TechT]

Yeah,if the cu.ft vol is right....

You might want to also check here for answers and ask questions as well.If you don't allready know about this site.
http://www.caraudioforum.com/vbb2/

 

[theamazingjime]

Instead of using MDF, you can use 7 or 11-ply BIRCH plywood. It's strong and stiff, and quite a bit lighter than mdf. Also, if it sounds a bit boomy to you, you could try adding some fiber-fill to the enclosure to absorb standing waves inside the box.

 

[theamazingjime]

Also-- are you using a sealed enclosure? 1 cf/side is a bit much for those type r's - you could use an enclosure as small as .6/side for them. Less box= less wieght!

 

[spyderx]

Also-- are you using a sealed enclosure? 1 cf/side is a bit much for those type r's - you could use an enclosure as small as .6/side for them. Less box= less wieght!

Sealed enclosure. And I did add some polyfill, about 1/2 lb to each chamber.

I'll check out birchwood and reduce the box size to mim volume. MDF is heavy as hell! I don't so much mind the weight but it's really loading down on my eibach springs and Tokiko illuminas! Can't be good, cuz my ride sux now!

 

[alanseijas]

Polyfil will make the box sound boomier. It actually makes the speakers think that they're in a larger box. Larger box=boomier, smaller box=tighter. Accoustical energy from a woofer travels in two directions: forward, and backward. The sealed box contains the backward energy. The waves travel from the rear of the woofer, and bounce off of the back wall of the box. They then hit into the rear of the sub. The farther the back wall (bigger box), the longer it takes these waves to hit the rear of the woofer. By adding polyfil, you are slowing the waves down because they now have to travel through the polyfil, and the woofer will "think" that the back wall is farther away (meaning that the box would be bigger).
Another major factor in box construction is rigidity. 3/4 MDF does not flex easily, thus making it a fabulous choice for enclosures. Any flexing that the box does means less bass. That's why we use concrete for our DB Drag competition vehicles. Concrete does not flex at all. Now of course I can understand the whole weight problem. There are some tradeoffs for BASS! (I'm not suggesting you use concrete!)
If you want tighter bass, lose the polyfil, and shrink down to minimum recommended size. This is the best scenario for both of your problems.

 

[slow talon esi]

first of all, dont use plywood, the acuostics of plywood is horrible, try dropping down to 1/2" MDF that should drop some weight without losing much sound quality, if you have any more questions e-mail me......... [email protected]

 

[alanseijas]

Nobody said the word "plywood" at all, and I guess you didn't read my recommendation about boxes flexing............ kid.

 

[slow talon esi]

ok read theamazingjime's post, the part about using birch plywood

 

[slow talon esi]

and i will admit i dont know EVERYTHING about sound systems (apperently you are a bass comp champ, which i give you alot of credit for) and i am sure your advise is much better than mine but im just trying to help, TO THE BEST OF MY KNOWLEDGE, ok

 

[alanseijas]

Yeah, it's okay. Welcome to the forum. All recommendations are welcome. Sorry! The last thing that i want is for somebody to be afraid of replying!

 

[slow talon esi]

thats ok, no hard feelings

 

[theamazingjime]

first of all, dont use plywood, the acuostics of plywood is horrible,
]

Not true.
Multi-ply birch is not only perfectly suited for speaker cabs, many top companies PREFER its sound characteristics as compared to mdf!!

Many big manufacturers use multi-ply birch for studio cabinets and guitar and bass cabinets because of it's light weight and strength.

Companies who use multi-ply birch construction include--
Marshall
Yorkville
Fender
E-v
JBL pro
Ect...ect...ect...

Do a google search-- you will be quite surprised!

 

[1 fast POS]

I'll back theamazingjime on the birch, I have read that alot of the pros prefer it. As for the weight issue, try the search button on weight reduction . I'm serious too, weight reduction is free and there are plenty of them. For every 1 pound of weight your car loses you can add a 1 pound of stereo.

I used to know this kid (fat fuck) that was in to mountain biking. He spent thousands of dollars on the best of the best bike ever. All along he is buying ultra light aluminum and titanium parts to reduce the weight of his bike by a matter of ounces. When all mutha fucu had to do was ride it from time to time and drop some pounds off of his ass. Did I go off topic???? Well the story is related, you figure it out.

 

[theamazingjime]

Just for kicks-- this is from Vifa's website...



The cheapest loudspeakers are built from vinyl covered pressed wood. These loudspeaker cabinets will nearly dissolve in water. Usually the back of the speaker is simply painted. I have seen many well-known speakers that cost hundreds of dollars built this way. Often, these loudspeakers use drivers from either Taiwan or China.

Better loudspeakers usually are made from MDF. MDF is less expensive than solid wood. Most speakers that look as if they are made from solid wood are actually made from MDF and then covered with a thin strip of veneer. MDF is a reasonable choice for building loudspeakers. However, it still is a compromise. If you strike MDF lightly with your knuckles, you will hear a high pitched sound. Birch and Oak would be better materials for building loudspeakers. Once again, the costs go up accordingly.

...and this is off a speaker building forum...

Don't build cabinets out of mdf. mdj is good because it has no voids, but veneer core plywood is much better for building portable cabinets. Round off the corners with a 3/8" rounding router bit so the corners won't splinter apart on you. You'll find veneer core holds up much better under the stresses of the road. That's why companies like jbl and electrovoice make the majority of their pro cabinets out of veneer core hardwoods

 

[slow talon esi]

i didn't know that 'bout the birch, guess you learn something every day............