Question about a used box I bought

[jatyro91]

Bought a used custom box with 2 XFL 12's. The guy says Dave The Box Guy made it, and it was custom made for the xfl subs. Problem is, he couldn't remember what it was tuned at. He says its somewhere between 32-37 hz. I mainly listen to rap and dubstep which I've heard is best at 32 hz, but I occasionally listen to rock, too, so I'm thinking 34-35hz is best for me? So, that's what I'm hoping it is.

This is the box and subs:

The dimensions I measured are:

Outer Dimensions: 36" W x 18" D x 14.5" H

He said the box was birch, and the wood seems to be 1 inch thick.

6" aeroport

The port is 11.5" deep

Port is 5.5" (approx) from the back wall

I don't know if there is any other internal bracing inside. From the photo and the dimensions I got is anyone able to figure out the displacement and hz? If so, will this do for my application? It would be surpassing my budget (again) to buy another box but with all the money I've spent I'd rather do it right the first time. So, if not, would it be worth buying a new box? One better tailor fitted to my type of music and the size of my cargo area? I have 39 inches width (narrowest point between the two wheel wells, with 2 inches cut off for finger space). 19 inches from the base of the cargo to the top of the back seat (not including headrest). I didn't measure the depth, but if possible I'd like it to be less than this box as it takes up about half of my cargo space.

Thanks in advance guys.

Edit: It's also worth mentioning that this is my daily car, so I would like to add grilles. As you can see, this box doesn't really have room to add any traditional ones so if anyone has any ideas for that (if its suggested I keep this box) I'd appreciate those, too.

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[jatyro91]

This is what I got without knowing the thickness of the port, or if there is any extra bracing. The only thing I'm unsure of is if the fact that they arent flush mounted changes anything?

So I guess I answered my own question unless I calculated something wrong? I guess the only question now is the cost worth the gain to get a lower tuned box better suited to my listening habits and my cargo bay? And my question about grilles?

 

[BOOMINGRANDPA 5,000+ posts]

that looks like 3/4" wood (try tape measure) if it is and he figured it as 1" that'll tune little lower but man u gotta take a sub out and see if any more wood inside there to ever know., if no other bracing in there i say just use it should be like 35.5hz if wood is 3/4 and no other wood.. set SS filter on amp at like 34hz u be fine unless u trying to rattle your teeth out at 25hz..

 

[jatyro91]

that looks like 3/4" wood (try tape measure) if it is and he figured it as 1" that'll tune little lower but man u gotta take a sub out and see if any more wood inside there to ever know., if no other bracing in there i say just use it should be like 35.5hz if wood is 3/4 and no other wood.. set lpf on amp at like 34hz u be fine unless u trying to rattle your teeth out at 25hz..

I used a tape measure for all these measurments. I'm definitely not trying to drop down to 25. 32 would be the lowest I'd go but I think 34 is where I want to be. Is 3 hz worth it?

 

[Jeffdachef 5,000+ posts]

I used a tape measure for all these measurments. I'm definitely not trying to drop down to 25. 32 would be the lowest I'd go but I think 34 is where I want to be. Is 3 hz worth it?

Just throw subs in there and play. A few hz is not gonna change much

 

[jatyro91]

That settles that.

Thanks guys.

 

[Boomin_tahoe 5,000+ posts]

37Hz? That's too high. For me anyway.

 

[Hertz Mafia]

Is there any bracing in the box? I came up with 3.8cubes tuned to 35hz but only 7" per port ft which is to small. And that box is on the small side. Idk how any box builder would build that box those number arnt working out for me.

 

[jatyro91]

Is there any bracing in the box? I came up with 3.8cubes tuned to 35hz but only 7" per port ft which is to small. And that box is on the small side. Idk how any box builder would build that box those number arnt working out for me.

I haven't taken the subs out to see if there's any bracing in the box. It was originally built for a 99 Nissan. I'm guessing that's why it's on the smaller side.

 

[thehardknoxlife 10+ year member]

Are you sure that's 1" birch? 1" Birch usually has 15 layers and is rare or special order in most areas. That looks like the 7 layer 3/4" from Home Depot.

 

[jatyro91]

Are you sure that's 1" birch? 1" Birch usually has 15 layers and is rare or special order in most areas. That looks like the 7 layer 3/4" from Home Depot.

I'll break out another tape measure but it looked 1inch to me. The guy could've been wrong and it not be birch?

 

[jatyro91]

Are you sure that's 1" birch? 1" Birch usually has 15 layers and is rare or special order in most areas. That looks like the 7 layer 3/4" from Home Depot.

No idea how I measured that poorly but you're all right. It's 3/4

 

[jatyro91]

Does that seem right? Can't take it apart right now to check for reinforcements but I will this weekend

Is there any bracing in the box? I came up with 3.8cubes tuned to 35hz but only 7" per port ft which is to small. And that box is on the small side. Idk how any box builder would build that box those number arnt working out for me.

What is so bad about that port size? Is it enough to call the box bad?

 

[thehardknoxlife 10+ year member]

The guy could've been wrong and it not be birch?

It's birch, as in, it has birch veneer on the outer most layers. The inner layers are most likely pine. The good stuff has hardwood in all layers.

Does that seem right?

Seems pretty close.

What is so bad about that port size? Is it enough to call the box bad?

Generally, most people aim for 12"-16" of port area per cubic ft. Aero ports tend to require less than your typical square port. All in all, if you don't hear port noise, you'll be fine.
I'd be more worried about where the box looks to have had water damage. When plywood gets wet, the layers begin to separate. The evidence of that is the missing layer on the corner.

 

[BOOMINGRANDPA 5,000+ posts]

No idea how I measured that poorly but you're all right. It's 3/4

wow I guessed it from pic even the tuning lol.. see tuned good enough now.. just see how it sounds, if it sounds good don't really matter how it looks unless it falls apart.. u shoulda seen 3.6 cf ported mdf I sold Friday very close to yours but 2.5x 13.5h port it had small bracing in it on all sides., but that was for orion hp 12's (they use smaller box) that box tad small for ab I think but most boxes ain't perfect.. u can see it look at my gallery pics **** it my sig won't go away...