View Full Version : Design Questions: Downfiring 2 SA-12 in 3.59 cu. ft. at 35hz aero ported

11-21-2012, 03:50 PM
Vehicle : 2010 GMC Sierra Crew Cab
Location in the vehicle: Under rear seat which will be lifted 3"
Space available (Length x Width x Height): 14"x63"x(10" front, 7" back")
Subwoofer make and model: Sundown SA-12
Subwoofer Size: 12"
Number of Subwoofers: 2
Type of Port (Kerfed, Slot, Aero, etc.): Aero
What type of music do you like?: Rap, Pop, and Rock
Is your goal SPL or Everyday Music?: Everyday
Tuning Freq (Hz): 35 (as recommended by Sundown site, but open to other frequencies)
Volume : 3.59 after all displacement except port

This will be the first enclosure I've ever made, and the first subs I've ever had. I'm going to lift the rear seats 3" and then install this box underneath them with about 1" of clearance to downfire with the ports facing forward. Will this be enough space for them? How much port do I need?
I liked the idea of the aero port because it seemed more space efficient and much simpler for a first box that isn't a cube.


I made a tentative design using SketchUp. The ports in it are 6" diameter and 8" long, I have no idea if these are accurate, mainly put them in to have a better idea of how the box should look.

Do you guys think this enclosure will sound good? If not, what changes would you suggest I make?

Any help is greatly appreciated :)

11-23-2012, 01:04 AM
Also planning on filling it with that poly-stuff. Do you guys think I need any braces? I'd really appreciate at least confirmation that I can realistically fit these subs cause I would like to order them while the sales are still good.

11-23-2012, 01:56 PM
2 6" aeros in that air space would need to be over 30"long each to get it tuned to 35. Youd need 2 4" aeros at about 16' each. Its gonna be rough to squeeze those in there, and youre going to need to re configure your sub and port locations.

If I were you I would go with a couple SA-8V2 instead justto cut down on the headache

11-23-2012, 02:02 PM
The other thing to watch for is how far your "lift" is. If you do not have enough clearance you will get some pretty negative results from the build.

11-23-2012, 04:18 PM
@pro-rabbit If I ordered a design from you do you think that 2 12s would fit or would I need to go down to 10s?

11-24-2012, 03:37 AM
My opinion is to go with the tens, thanks for using the format for this thread! Good to see someone did their homework before posting!

11-24-2012, 12:05 PM
My opinion is to go with the tens, thanks for using the format for this thread! Good to see someone did their homework before posting!
Thanks! What modifications should I make to my design to accommodate 10s? I haven't bought the subs yet, all I've ordered is an AQ2200 after a long discussion on another thread. I ended up deciding to get the Alpine SWR 12 in exchange for a higher quality amp than I originally planned to purchase. If I bought the SWR 10s would I still be gettin all the value out of my amp?