I was extremely bored, and figured I'd play around in photoshop... well, I figured I'd sketch out what I want my speaker setup to look like when all is said and done.


obviously not drawn to scale...
(and that'd be one massive box! )

Blue=Plexiglass
Yellow=port
grey=inputs


Only thing I think I might change (didnt feel like redoing the whole image) would be to make the 15" not quite as recessed and then make the box not quite as deep...

and obviously, the blue part (top) is the front of the box

Anybody here good with sound mechanics and think that box would sound decent?
Any comments are appreciated

I don't know a lot about subs, but I heard you were not supposed to mix sizes.... but then again.... I don't know too much about subs.

I think this is what your looking for, great site lots of info.
http://www.the12volt.com/caraudio/boxes.asp
take a look at the bottom of the page for links to sub making and formulas for porting, tunning, etc.

mixing sizes is bad if you do not have a different chamber for each different size of sub. mixing the sizes of subs is good sometimes to get a broader frequency range out of the speakers. mixing sizes is not done in most cases because of how it would look and possibly not having enough space to fit the desired design of the box.

Looks like his design has the seperate chamber requirement licked. Should he use some sort of dampening between the chambers? This would be really cool to see.

If you do this, crossovers will be VERY important for Sound quality. I can't stress this enough. And use woofers of the same line. You don't want ANY overlap at all of frequencies between woofers, because different sizes won't mesh well, they all react differently. You'll need to have seperate amps as well, setup witht he gains just right.I'd suggest a 15 and two 8'* then in this config. Have your 15 to 0-say 80hz, then the 8'* do 80hz to 120, and 120 and up handled by the speakers. You don't want to go much higher then that on the subs.

This is a little out of my league, but do the subs list their frequency response? I don't mean a range, I mean a GRAPH? It would make it alot easier to match/tune them. I would expect he'll end up with different manufacturers to get this right.

I'd really like to see this box built. Cool as hell.

Nah you don't want different manufactueres at all. You need to have the same line of subs, because when the sound jumps from the 15, to the 10/8 you'll need them to sound exactly the same, or they'll get muddier or tighter depending on which way you go.

I'd suggest 8'* because between them and the 15 they won't overlap as much with a full frequency range before cutoff. Most 10'* can play pretty low, anything decent will do below 30 hz.

Looks good. So they drop off ALMOST before the overlap. What about a bandpass filter to clean up the transition?

Well that'* something i drew in paint, not any real numbers for any specific subwoofer. I think a bandpass filter wouldn't be complete solution. You'll need atleast 3 crossovers for just the subwoofer setup here.

Like i said before, you'll want to have the different sized subs on different amps. Say the two 8'* on a two way, bridged or not, doesn't matter too much, and the 15 on say a monoblock. Amp selection will be key for this, as you will need FULLY adjustable crossovers on both subwoofers. The 15 will be easier to tune then the rest, that'* for sure. You'll also want a deck/4 way amp that has a high high pass setting for the speakers, around 120 hz or so.

For the 15 you'll have the amplifier do a low pass filter, around 80 hz or so (generally a good speaker/sub crossover point) The 8" amplifier will run a high pass filter around 80hz or so and only frequencies above it will go out. Both of these should be adjustable by a **** on the amplifier itself, so you can finely tune it. My DEI amp has this, and I LOVE IT.

Now geting the 8" to crossover to the speakers will be a lil trickier, you could use a electronic crossover before the 8" amplifier, one built into the deck, or an inline one in the RCAs thats non adjustable.