truck box help

[2010gmc]

So i need some advice on deciding a new setup for my 2010 gmc sierra crew cab. As of now, i have a bad setup with 2 rf p1 12's under the backseat sealed. I wanted to do a ported box like this: http://www.youtube.com/watch?v=rMqdmKnwjL0

however, i talked to a local audio store owner and he said i could never get a good sounding ported box under my seats, any thoughts? He said i should just do 2 JL 10 inch w1's sealed because thats the best setup he's heard in a truck like mine.

[CleanSierra]

I'll bet that local audio shop owner CONVENIENTLY sells JL audio doesn't he? I've seen a couple of Sundown(all the way up to 4) 8s under the rear seat of your same truck, ported, and it would blue you away the output they provide. The SA 8, and Skar MA8 van work very well in limited space and still be ported. You have to get creative with the design, but it can definitely be done.

Question: Do you have an extended or crew cab?

[2010gmc]

Crew cab, and would you rule out 10's? I've never heard 8's in person and I just feel like they wouldn't hit low or hard, I know that sounds ridiculous but I really wanted to do 10's. Also, he doesn't sell jl himself but the other store that is owned by the same people does, but he also sells sundown, which is what I wanted to use. I don't think he was trying to force me into buying something he sold because he also told me getting him to build that box would be really expensive, but I highly doubt he's ever heard a ported box like in the video I posted

[CleanSierra]

I wouldn't rule out 10s, but you'll likely lose output going with sealed. I've heard downfired 10s in that truck and they sound good. The way the box is in that video, I've never seem done with 10s. The W1 isn't a very high power handling sub, and won't have monster output, in any cone size it comes in. Sundown SA8s can seriously get low and loud. I've heard the MA8s(pretty much the same sub, just made by Skar) in a local guy's Mazda and they dug low and get loud. They also sounded very clean while doing it.

[CleanSierra]

Don't be fooled by the myth that big subwoofers get low and smaller subs are "punchier" and tighter. The box dictates how the subwoofer is going to perform.

[2010gmc]

So what would you suggest, I'm pretty sure I can't fit sa-8's down firing so I pretty much have to do forward firing I think. Have you heard forward firing 8 inch subs in a truck before?

[2010gmc]

If I could do 1.2 cubic feet per sub would that be enough? Too much? For 2 sa 8's

[Brandonbkd]

Check out Rusty's truck. He's now got 4 8's ported under the rear seat and it looks plenty loud to me lol

http://www.stevemeadedesigns.com/board/topic/171340-4-dc-m3-8-inch-subs-in-my-silverado-build-over-the-weekend/?hl=%20wca%20%20rusty

[The_Iceman]

If you can work it in there, you can fit a 10 in 1.2 ft per sub, that's what I'm doing with mine. Shit I messaged sundown and they told me the perfect ported box for SA-10 was 1.0 cubic ft at 35 Hz.

[2010gmc]

I saw that truck on YouTube, but I don't know if I want to do 4 8's. And I've seen someone put Re SE 10's under the back seat in a truck like mine so I know it can be done but you have to make the box come further out from under the back seat I think, and I don't know if I want to do that.