Looking for some help with a box for my Zv4

[Syphlyn 1]

Hey guys,

 

Currently in the works of trying to figure out a box that will work with my Zv4.

 

Here's some info:

 

- Going in a 2000 f150 ext cab in place of the smaller rear seat.

- Using my Saz-2000D amp

- Sundown Zv4 12, suggested 2.25-2.75 cu ft

- Wanting tuning around 30hz-32hz

- Max Dem: W: 17 | D: 18 | H: 26 or so |

- Would prefer sub to fire upwards.

- I love rap music and bass heavy electronic similar to white clouds from decaf or lights from bassnectar.

 

Here's my original box and design: http://imgur.com/a/WqOOl

No sure how well it'll work and if there's enough port area.

 

So here's another very similar box with a couple small changes that move me from 14.85 sq inches of port to 15.74. Not sure if that'll make a difference: http://imgur.com/nZEi3zR. I know the width is 1 more inch but I think I can squeeze it in.

 

Feel free to design a completely new box or suggest changes. I'm not sure but I heard torres miscalculates the box volume (slightly larger) resulting in a slightly lower tuning, not sure if there's any truth to this.

Edited August 20, 2014 by Syphlyn

[j-roadtatts 1,129]

I would guess the confusion with the Torres calc comes from the port length being measured down the center, not the length of the inner port wall. As with any program you must enter the numbers in the correct sequence.

Port area has a lot to do with power being fed among other things. Generally you can't go wrong with more port area.

Have you tryed modeling with WINisd? Would be a good start.

[Syphlyn 1]

I would guess the confusion with the Torres calc comes from the port length being measured down the center, not the length of the inner port wall. As with any program you must enter the numbers in the correct sequence.

Port area has a lot to do with power being fed among other things. Generally you can't go wrong with more port area.

Have you tryed modeling with WINisd? Would be a good start.

My port is 34.5 inches long down the center line of the port. Does torres use the inner wall?

Edited August 24, 2014 by Syphlyn

[j-roadtatts 1,129]

IIRC Torres measures down the center.

If the port uses a wall that continues past the port, the inner wall of the port should be phisically half the ports width shorter. So with a 4" wide port, measured down the center, will need the inner port wall 2" shorter than where the port ends. The speaker still see's the extra port volume, and that volume is part of the port volume. Not the net volume.

This could cause the "miscalculation" you heard of. Has been awhile since I used the Torres, but was accurate for me.

[Syphlyn 1]

IIRC Torres measures down the center.

If the port uses a wall that continues past the port, the inner wall of the port should be phisically half the ports width shorter. So with a 4" wide port, measured down the center, will need the inner port wall 2" shorter than where the port ends. The speaker still see's the extra port volume, and that volume is part of the port volume. Not the net volume.

This could cause the "miscalculation" you heard of. Has been awhile since I used the Torres, but was accurate for me.

So if my port is 37 inches down the center line and one wall is of the box walls and keeps going that effectively adds another 1 3/8 (my port is 2.75) inches to my port length making it 38 3/8?

[j-roadtatts 1,129]

The physical port length given in the Torres is the inner port wall length. The effective port length is half the port width longer.

I would go with the wider port. The only thing I see in the sketch up I would worry about is the port ending so close to the corner. Could change the effective port length. From the box dimensions and psychical length in your link you should be good. I think the sketch just makes it look closer than it is.

[Syphlyn 1]

The physical port length given in the Torres is the inner port wall length. The effective port length is half the port width longer.

I would go with the wider port. The only thing I see in the sketch up I would worry about is the port ending so close to the corner. Could change the effective port length. From the box dimensions and psychical length in your link you should be good. I think the sketch just makes it look closer than it is.

Oh god these designs are so old lol. Here's my new updated one: http://imgur.com/a/rsjTk

 

There's 5.5 inches between the end of the port wall on the inside and the other wall, so I would think i'd be fine. My center line down the middle is 37 inches but if I add the double baffle and the two port walls and add 1 3/8 I don't get 37.

 

I'm extremely confused lol.

Edited August 30, 2014 by Syphlyn

[j-roadtatts 1,129]

The effective (acoustical) port length is given on the bottom. You are confusing the physical port length with the effective.

[Syphlyn 1]

holy shit! never noticed that. Wow thanks man!