18" BTL Box Design Critique...

[SHiZNiLTi 10+ year member]

1. How do you think the overall design will perform in my blazer?
   
2. What would you do to prevent flexing?
   
3. Is there enough port area?
   

7.3 cubes ~ 31hz ~ 105sq.in. of port...

I can't believe I just spent this much on a sub...

I've gone through alot of design's and I'm thinking about doing somethign like this..

Please post up any other design's that you think would work out better for me.

Thanks!

Click to read more...

 

[geowick07 10+ year member]

1. From what i have heard and seen, you may be better off with the sub facing up in a blazer-suv setup. but, try it out and see what you think.

2. Personally, definitely double baffle, and some 1.5" wooden dowel side-to-side and top-to-bottom. Some will recommend all thread( threaded rod), but you will see the thread and nuts and washers outside of the finished box. Personal preference = wooden dowel.

3. Port area seems a little low, but that could be just the design of the box itself. And being tuned that low. Have a look at this. Subwoofer Enclosure Design

I took the liberty of filling in your specs, and the dimensions stayed the same except for the overall depth of the box. It went up from 27" to 30". Don't know what your max dimensions are, but if i went over, feel free to play around with that box calculator til you find something that works for you. But, if you are set on that box you designed, it should be fine.

 

[angrytrucker78 10+ year member]

27 inches deep with a height of 19 is pushing it to begin with in a 2 door Blazer. No way 30 is gonna fly.

 

[rpfuror 10+ year member]

LOL, that 3d drawing is a box I designed that was 11 cu/ft @ 32Hz,

If you what something custom for you application let me know

 

[Goldtaz1 10+ year member]

PM sent dude.

 

[SHiZNiLTi 10+ year member]

Has anyone tried sub on top with a vertical port?

 

[rpfuror 10+ year member]

I done it.. in that case I would typically build the box in a CRX design.

 

[j3bus2k3 5,000+ posts]

That RE calc is flawed. It does not take into account driver displacement...

Do sub up, port back with about 120sq.in. of port....

 

[SHiZNiLTi 10+ year member]

That RE calc is flawed. It does not take into account driver displacement...
Do sub up, port back with about 120sq.in. of port....

Thanks for info j3bus2k3, I was just using that RE calc as a quick guide to work off of. I've got an expereinced box builder helping me out with the design now. I'll post up a work log soon //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

angrytrucker - 30" would still fit, but I would only have about 2" between the port and rear hatch which is no where near enough space, thanks for catching that though and making me re measure everything.

I'm going to go with these measurements:

37W x 18H x 26D

Port Dimensions:

16.5"H x 5.5"W

Port Length:

29"

Tuning:

32hz

 

[saywhat? 5,000+ posts]

6 cubes @ 33. crx style

/thread

 

[SHiZNiLTi 10+ year member]

LOL ... /Thread - add the port area in there. Why do some people say 120sq.in. others say 90sq.in.?

If more port area makes it louder then why wouldn't everyone try to do the max port area?

after this question we can do a /thread //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[mazdakid 5,000+ posts]

because the more port area you have the longer the port has to be to stay tuned low

 

[mazdakid 5,000+ posts]

if you went with 6 cubes then 80" of port would be enough

 

[saywhat? 5,000+ posts]

6 cubes......100 sq inches......33hz. hit me up for a design if you need one. Id be more than willing to throw something together that would even look good //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[bamaboy 5,000+ posts]

do 15 sq in per cube, good rule to use