Does this box seem right?

[ilikeradios 10+ year member]

I am getting a box built for my truck.

It is in a Crew Cab and will be replacing the rear seat.

Right now I am running a set of 12" Skar VVX version 1's

I will most likely be upgrading to a pair of Ultra's in the near future.

What I wonder is if 2.25 per driver is too large?

I am running a ton of power to them via a RP 2000.1

Would going smaller help with power handling?

Basically will the Ultra's do good in a 2.25 sq / each tuned to 30?

Would you change anything?

From the builder...

Using your dimensions of 14"H x 48"W x 18"D we are at 5.29^3ft gross vol. Slot port, 12.5"H x 3"W tuned to 30Hz. After all displacement, 4.51^3ft net vol. Driver hole cut to 11.250”. Built from 3/4" High Quality, Five Ply North American Birch; A very Stable and Strong panel that is Tough, Durable, and Light Weight, and has been shown to perform very well acoustically! A 1.5" thick reinforced baffle board and fully braced & supported where needed. Deflection boards in all the vertical corners to kill standing sound waves, this reduces distortion and adds strength to the enclosure, deflector boards are made from .75” birch strips and fastened with ribbed fasteners. The port panel ends and corners are rounded to eliminate port noise. Seams are cut matched and panels interlocked for added strength. Seams fastened with TiteBond heavy duty construction adhesive. Seams are first clamped then fastened with 2" countersunk drywall screws.

Click to read more...

 

[Boomin_tahoe 5,000+ posts]

I am getting a box built for my truck.
It is in a Crew Cab and will be replacing the rear seat.

Right now I am running a set of 12" Skar VVX version 1's

I will most likely be upgrading to a pair of Ultra's in the near future.

What I wonder is if 2.25 per driver is too large?

I am running a ton of power to them via a RP 2000.1

Would going smaller help with power handling?

Basically will the Ultra's do good in a 2.25 sq / each tuned to 30?

Would you change anything?

From the builder...

Using your dimensions of 14"H x 48"W x 18"D we are at 5.29^3ft gross vol. Slot port, 12.5"H x 3"W tuned to 30Hz. After all displacement, 4.51^3ft net vol. Driver hole cut to 11.250”. Built from 3/4" High Quality, Five Ply North American Birch; A very Stable and Strong panel that is Tough, Durable, and Light Weight, and has been shown to perform very well acoustically! A 1.5" thick reinforced baffle board and fully braced & supported where needed. Deflection boards in all the vertical corners to kill standing sound waves, this reduces distortion and adds strength to the enclosure, deflector boards are made from .75” birch strips and fastened with ribbed fasteners. The port panel ends and corners are rounded to eliminate port noise. Seams are cut matched and panels interlocked for added strength. Seams fastened with TiteBond heavy duty construction adhesive. Seams are first clamped then fastened with 2" countersunk drywall screws.

Oh really? He can tell a difference between an MDF enclosure vs. a birch one???

 

[ilikeradios 10+ year member]

Oh really? He can tell a difference between an MDF enclosure vs. a birch one???

He is trying to sell a box, it is how he make his money.

I want a birch box as I have never had one and am hoping it cuts down on the weight a little.

What is up with him saying 5 ply? I thought it was 7 or 14 ply?

 

[SuperDuty350]

He is trying to sell a box, it is how he make his money.
I want a birch box as I have never had one and am hoping it cuts down on the weight a little.

What is up with him saying 5 ply? I thought it was 7 or 14 ply?

Depends on where he gets his lumber. Sometimes cabinet grade is 5ply. Or he could be referring to the core and the birch being the faces

 

[ilikeradios 10+ year member]

Anyway I have seen his boxes and they seem quality.

Am I good with the size and tuning?

Also Ultra's are larger than my VVX's so the net will be a little smaller, not sure by how much though

 

[Boomin_tahoe 5,000+ posts]

He is trying to sell a box, it is how he make his money.
I want a birch box as I have never had one and am hoping it cuts down on the weight a little.

What is up with him saying 5 ply? I thought it was 7 or 14 ply?

Yeah I can understand that. However, saying false info isn't gonna do nothing as it's been proven already. Should be/hear no difference between 2 diff woods.

Real baltic birch comes in 11-13 ply. That must be reg plywood he's using. Ply comes in a variety of layers....just depends upon how much $$ you wanna spend.

My next enclosure, I'll be getting some baltic birch. Stuff isn't cheap but is much lighter than MDF. That enclosure in my avatar is made from ply.

 

[ilikeradios 10+ year member]

here is an example of his work

 

[kr15 5,000+ posts]

I had my ultra 12 in 2.5cu and it handled a sax1200 at 1ohm with ease. I would do at LEAST 2.25, low 30s tune is perfect

As for the Skars, they'll laugh at that power. The v1 was a good driver, i had a pair on a dd m3 at 0.5 daily for like 3 years

 

[ilikeradios 10+ year member]

I had my ultra 12 in 2.5cu and it handled a sax1200 at 1ohm with ease. I would do at LEAST 2.25, low 30s tune is perfect
As for the Skars, they'll laugh at that power. The v1 was a good driver, i had a pair on a dd m3 at 0.5 daily for like 3 years

I know about the Skars, I bought them when they first came out 5-6 years ago and have been beating on them since. First I had them on a 1,000 watt Fosgate, then a dirty *** Hifonics and now on the RP 2000.

Even though they still sound good and have no issues I am thinking about selling them along with the 4 cube net box I have them in.

 

[kr15 5,000+ posts]

The Ultra is indeed a better driver, I think it will play more linear than the vvx. It will definately be louder on the TL, but not necessarily to the ear. Its probably not gonna be earth shattering tho.

My opinion about Kevin aside, the v1 was a very capable driver. I gained on drop in over the SAs. Alot of ppl found the vvx to be too bottom heavy compared to the SA. Which i experienced too. The ultra has no issue maintaining a nice response. The motor is strong enough to keep up away from tuning