Building Custom Box

[My LT4 Z]

Hey there. My brother just got a 1997 A4 Audi, and he wants to put a system in it, and instead of hmi paying close to $200 for a box with Dual subs in it, I wold him I would build him ma box and we can use the $200 to get a better set of subs. I drew up some plans yesterday, and I was wondering for some pointers to get the best sound out of it. The box will be 40in wide and 15 in deep. The bottom will rise 4 in, and then come in on a 45* angle where the subs and amp are mounted.

Its hard to explain, so heres a pic kind of



Anyway, any suggestions on the box?

[nemocamaro]

make the port holes smaller. and you really dont need to make it that big

[My LT4 Z]

I wanted it big enough to fit flush in the trunk. And I was thinking of putting wood on each side of the amp to box off both subs so theres less air and then putting only one port hole for each sub.

[nemocamaro]

that sound like a good idea. google fluid dynamics and try and learn something about the subs and how much air they put out to see what size holes you would need.

[My LT4 Z]

Where could I find info about the subs and the air they put out?

BTW, the subs hes looking at are 12" Infinity Dual-Coil off Best Buy. Not the greatest, but theyre $100 a piece on sale and he can get a 4 yr warrenty in case he blows them

[nemocamaro]

just find them on bestbuy.com and the specs should be there

[My LT4 Z]

what specs do I look for and how do I relate that to the size of the box and port holes. If its hard to explain, a url would be good and I can do my own reaserch.

[LT1 Weezy]

Look at the dimensions of mounting depth, cutout and outer diameter, since you doing a ported box...you will want driver and port displacements..just go to infinity's website and it gives you all the specs on the sub your using.......infinitysystems.com

[ricehammer]

Look on Infinitys web site and see what box configurations they suggest for the subs. Box volume, port diameter and port length are your constraints. Meet these constraints and design the box to best fit the trunk. You may wind up having to separate the subs on both sides of the amps to cut down on box volume for each sub. Dunno, you didn't post the height of the box .

[My LT4 Z]

The box is 17 inches tall. And Il check theyre website in the morning. and I have to change my setup because the measurements on the internet were wrong. The trunk is 34 inches wide in the smallest part, not 40 so I wont have room on the box for the amp. Im gonna mount it on the rear window ledge and have him throw some tints on. So that way the box can be thinner and I can just mount a piece of wood on each side to make it flush

[HurstHardtop94]

try making a vent at the bottom instead of ports. to many ports can make "port noise." nothing worse than making a box and it sounding like a fat man with a sinus problem. that and venting just looks cooler. i've also heard of dampening material that you place at the very back part of the subs chamber that forces the air out more effecientlly to make better sub response.

[pmr253]

He should spring for the Apline Type R's, you can punish the hell out of them and they sound good and are underrated by the factory.

[HurstHardtop94]

all i use is alpine, my explorer and my z28 have alpine... even my g/f's honda is all alpine... in my experience best all around company

[pmr253]

Originally Posted by HurstHardtop94

all i use is alpine, my explorer and my z28 have alpine... even my g/f's honda is all alpine... in my experience best all around company

I have a JL VR's all the way around on my car with the single Alpine 12 in the back. I honestly like the quality on the alpine's better than the JL's.