Help me design my box! Please.

[Bun-Bun 10+ year member]

Ok so its time to build my box... heres the trunk:

The dimensions of that dip are 42" wide (bigger but with the rounds on the bottom of it thats the biggest i think i can fit), 22.5" deep (to the curves you see in the second pic. theres another 6" to the back of the trunk from there), and 13.5" up to the bottom of the tire.

Ok so I want to fit the box in that dip in there. I would also like to keep the spare tire although after playing with some idea's i think i need to get rid of it. Although it looks like in the above two pics that the angle is really bad and if I could some how get it to sit more level and/or raise it a bit I could get a few more inches of height on the box.

So with keeping in line with trying to keep the tire I came up with these two idea's:

Ok both of those idea's I think ****... the top one the port is too complicated and takes up way to much space... I don't think I can get enough volume for my subs with that design. The second one... well... limited to normal ports due to size and thats getting kinda crazy with round ports I think...

Then I started looking around at some other desings and got some new ideas and wanted to try this http://img355.imageshack.us/img_viewer_framed.php?loc=img355&image=jake2.jpg&gal=img371/6311/bonesninja22.jpg but but couldn't get it to work with the lack of depth.

So I came up with this...

That box is 42" wide x 14.875" high x 22.5" deep. Port is 40.5"x1.375" x19.675" tuned to 34hz @ 5.0ft^3 box volume calculated with WinISD.

This design assumes I am either getting rid of the spare or raising/leveling it off somehow.

So a few questions...

1. So is that last design a good idea or should I do something else?

2. Can I put the subs right next to eachother like that?

3. How do I determine what port area and tuning I want? I had these in a 5.12ft^3 box tuned to 34 hz before that a local shop designed for me but I switched cars and wan't to do this all myself this time. And comparing this to what I had the port before was dinky in comparison.

The drivers are 4 10" Memphis PR's running on a 1000D (1100wrmsx1)

Thanks for any advice!

Click to read more...

 

[NissanKicker 10+ year member]

My work partner had that same EXACT setup in a Jimmy...

... If you want optimum... you need about 6cuft +

*1.5cuft each sub... you should be able to get away with 1-1.25cuft each *

 

[PV Audio 5,000+ posts]

Is that inventor? Cause that program's z-axis always ****s with my head.

 

[Bun-Bun 10+ year member]

My work partner had that same EXACT setup in a Jimmy...... If you want optimum... you need about 6cuft +

*1.5cuft each sub... you should be able to get away with 1-1.25cuft each *

Well with that last design I am at 5.0^3ft net volume so 1.25 per sub which I think should do ok. It's about what I had last time just with a lot more port area. My last box was maye 3x6x8 port or something like that... was small.

But I don't even know what the advantages of going with a bigger port? I just tried to get as big of a surface area as I could with that last design but not get to close to the back although I could put a bend in it.

Speaking of which how do you figure out port length on bending ports? Is it just the centerline length that ='s the port length? Cause I could put a bend in there and maybe go to a 2" wide port for 80sqin area vs the current 56... I base the 80sqin on DDaudio's guide and the last box in the sticky in this forum.

Is that inventor? Cause that program's z-axis always ****s with my head.

It is solidworks. What's wrong with inventor's z-axis? (I use both at work along with microstation)

 

[PV Audio 5,000+ posts]

Solidworks I meant then. Whatever is shown in the picture makes shit look oblong when it really isn't.

 

[Bun-Bun 10+ year member]

Solidworks I meant then. Whatever is shown in the picture makes shit look oblong when it really isn't.

Hmm I never noticed anything like that... I do notice the shadow's with the lighting sometimes make things look weird.

Here is another question. Top mounted firing up subs vs front/rear mounted firing front/rear subs?

 

[PV Audio 5,000+ posts]

Fire towards the license plate. You rarely want to upfire in a car because you can easily choke them off.

 

[Buck 5,000+ posts]

pm this guy: psych0ticnemes1

 

[Bun-Bun 10+ year member]

Fire towards the license plate. You rarely want to upfire in a car because you can easily choke them off.

What do you mean choke them off? Given the layout of my trunk there will be more room above the subs firing up then there would be in front of them firing towards the back.

Like there will probably be about 1ft from the top of the box to the trunk lid in a firing up position as opposed to 5-6in from the back of the trunk to the subs in a rear firing position.

Does port direction matter?

 

[Bun-Bun 10+ year member]

Here are a couple more designs... what do you guys think?

Specs are:

5.0ft^3 tuned to 34Hz. Port is 5.5"x14.5"x30-7/8". Overall dimensions are 42"x22.5"x16".

EDIT: Should note that it was an after thought but the front and back of the box will be the outside most peices. As it is the port looks a little goofy.

 

[Bun-Bun 10+ year member]

No one?

 

[Bun-Bun 10+ year member]

Ok spent some time continuing off the full width port...

the last two kinda say screw the spare tire but meh...

Port is 40.5inx1.25in x 19.25in long. Box 5.08ft^3 net and tuned to appraximately 33.2Hz. This goes for all 3.

 

[Bun-Bun 10+ year member]

There it is... the final design.

just under 5ft^3 net. Port is 2"x40.5" x 27.25" long. Tuning is ~36.3Hz.

Let me know what you think.

 

[Bun-Bun 10+ year member]

Ok I lied... here is the final design.

Decided to split into two chambers to simpify building and eliminate crazy bracing.

Again each chamber is 2.5ft^3 net with ~40in^2 of port area tuned to 36hz.

The reason I increased the tunning from previous designs is I was told by a memphis dealer that because my car is built like a brick house (07 MGM) that I should tune a bit higher to prevent loseing cone control as my memphis PR's Fs is 33Hz. I had them tuned previoulsy to 33Hz but that was in a 88 Beretta.

 

[GearGuy2001 10+ year member]

nice mgm I just put 2 RE SR10's in my 97 (look around youll see my build log)