Which SPL Design?

[matt_martin87 10+ year member]

I'm building an SPL box for 2 12 cvr's in a 06 Impala. He wants the port to face into the cabin. Sd of both subs is ~165 sq in.

I've been told to use up to 100% of Sd.

Here is where I'm running into some difficulties. Both subs and 165 sqin of port can't fire into the cabin. There isn't enough room. The most port area I can get is ~65 sq in this way.

If I tweak the placement of the subs, I can get all 165 sq in of port firing into the cabin. This requires me to place one of the subs on the side and one facing into the cabin. I worry about phase issues with this but those may be negated by the sheer amount of port area. I also wonder whether having both subs facing into the cabin will make much of a difference than moving one to the side.

Have a quick look at the designs and tell me which is better suited for his application.

Both these are 3.5 cubes at 48hz.

Click to read more...

 

[Mitch86 5,000+ posts]

Im no expert but I dont think the first one would be a good idea.

 

[tuckintaco93 10+ year member]

how tall is the front of the box mabe you could stagger the subs

 

[basscort2009 5,000+ posts]

first one is terrible idea. bad phasing issues and cancelation with the port being L'ed off and the subs being not on same plane. SPL is straight foward. just face them both foward and do 25 inches of port area for straight spl burp box. do 3.5-4 cubes with 90-100 inches of port.

 

[matt_martin87 10+ year member]

The box is only 16 inches tall. The 2nd design incorporates staggered subs. I'll only have 65 sq in of port. 90-100 is out the question.

 

[basscort2009 5,000+ posts]

u can get a bigger box than that in a 06 impala. u must be doing somehting wrong.

 

[matt_martin87 10+ year member]

The max dimensions are 32w x 32d x 16h

 

[RAM_Designs 5,000+ posts]

You could do a sort of clamshell design to get more port area in there with the subs and port on the same side of the box.

 

[matt_martin87 10+ year member]

Do you happen to have an example of that design?

 

[RAM_Designs 5,000+ posts]

Do you happen to have an example of that design?

(not mine)

http://img175.imageshack.us/img175/1668/4portedclamshellorvshap.jpg

 

[matt_martin87 10+ year member]

I'd be interested if I knew anything about designing them.