15 bl box problem

[NB50 206]

I'll tell ya, I'm not sure the eurosports calculator is all that accurate. I got 4.3cuft net, giving sub and port displacements it came to 5.43cuft at 14"H x 30"W x just under 28" D tuned to 36hz the port would be 5.5"W x 14"H and about 19.5" long. That keeps the max 16sqin per cuft recommendation from Fi. If we drop the tuning to 33hz, to keep the same dimensions you drop to 4.2 cuft net and 15.5sqin port area, port would be 5 1/4"W x 14"H and 23.5" inches long. These are pretty quick calcualtions, no bracing and still within Fi specs.

Might want to recalculate those, I fail to see how you can have a 14"h port when the enclosure is only 14"h.

[drumminian 0]

damn I didn't even see that but if the ports are 13.25 plus the .75 mdf on both sides would this effect tuning?

[Duran 387]

damn I didn't even see that but if the ports are 13.25 plus the .75 mdf on both sides would this effect tuning?

Yup, and port area.

[drumminian 0]

damn I didn't even see that but if the ports are 13.25 plus the .75 mdf on both sides would this effect tuning?

Yup, and port area.

well damn can anyone get me the correct dimensions for an enclosure with the same tuning and correct port length?

[thebiggmann12 14]

y dont u just check out the re box calculator? its fairly simple to use and sorta accurate...enough for me anyways.

[drumminian 0]

y dont u just check out the re box calculator? its fairly simple to use and sorta accurate...enough for me anyways.

bc I heard the RE calc is really bad?

[Duran 387]

Use this one: PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES

The RE calculator is inaccurate if your port has a bend.

[jcarter1885 994]

Use this one: PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES

The RE calculator is inaccurate if your port has a bend.

x2 or do the math by hand (best way).

[drumminian 0]

blah I guess I'll have to pay someone around me to design it or whatever I have no idea what to do to make the port length the length I need or anything

[thebiggmann12 14]

do some reading, i personally used the re calculator and i love my box, i know its off, but it doesnt seem like its off enough to matter.

[drumminian 0]

well every time I enter what I have for the box tuned at 33hz I only get 24 inches of port

[altoncustomtech 773]

I'll tell ya, I'm not sure the eurosports calculator is all that accurate. I got 4.3cuft net, giving sub and port displacements it came to 5.43cuft at 14"H x 30"W x just under 28" D tuned to 36hz the port would be 5.5"W x 14"H and about 19.5" long. That keeps the max 16sqin per cuft recommendation from Fi. If we drop the tuning to 33hz, to keep the same dimensions you drop to 4.2 cuft net and 15.5sqin port area, port would be 5 1/4"W x 14"H and 23.5" inches long. These are pretty quick calcualtions, no bracing and still within Fi specs.

Might want to recalculate those, I fail to see how you can have a 14"h port when the enclosure is only 14"h.

No, the math is right, I'm just a damned goof for saying it was 14", the port height is 12.5". 5.25 times 12.5 is 65.6 divide that by 4.2 (net box size) that equals 15.6sqin per cuft.

like i said earlier all the math is a little quick, but good enough to work by. The enclosure and the tuning are correct, I just wasn't thinking when I mentioned the port height.

Edited February 11, 2010 by Alton

[drumminian 0]

I'll tell ya, I'm not sure the eurosports calculator is all that accurate. I got 4.3cuft net, giving sub and port displacements it came to 5.43cuft at 14"H x 30"W x just under 28" D tuned to 36hz the port would be 5.5"W x 14"H and about 19.5" long. That keeps the max 16sqin per cuft recommendation from Fi. If we drop the tuning to 33hz, to keep the same dimensions you drop to 4.2 cuft net and 15.5sqin port area, port would be 5 1/4"W x 14"H and 23.5" inches long. These are pretty quick calcualtions, no bracing and still within Fi specs.

Might want to recalculate those, I fail to see how you can have a 14"h port when the enclosure is only 14"h.

No, the math is right, I'm just a damned goof for saying it was 14", the port height is 12.5". 5.25 times 12.5 is 65.6 divide that by 4.2 (net box size) that equals 15.6sqin per cuft.

like i said earlier all the math is a little quick, but good enough to work by. The enclosure and the tuning are correct, I just wasn't thinking when I mentioned the port height.

well I threw your dimensions into the cal on here PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES and It only comes out with 29.36 inches for the port? is this right? I thought it should be around 48-64sqin

[altoncustomtech 773]

No, the math is right, I'm just a damned goof for saying it was 14", the port height is 12.5". 5.25 times 12.5 is 65.6 divide that by 4.2 (net box size) that equals 15.6sqin per cuft.

like i said earlier all the math is a little quick, but good enough to work by. The enclosure and the tuning are correct, I just wasn't thinking when I mentioned the port height.

well I threw your dimensions into the cal on here PORT Size Calculations and Formulas for WOOFER and Subwoofer BOXES and It only comes out with 29.36 inches for the port? is this right? I thought it should be around 48-64sqin

The answer is in bold, but that's only IF you're comparing apples to apples. All the data needs to be entered the same.

Hell I got 27"

I dunno, I know that the calculator I use and built enclosures by has always seemed good, just go with whatever you feel most comfortable with I guess.

[NB50 206]

I'll tell ya, I'm not sure the eurosports calculator is all that accurate. I got 4.3cuft net, giving sub and port displacements it came to 5.43cuft at 14"H x 30"W x just under 28" D tuned to 36hz the port would be 5.5"W x 14"H and about 19.5" long. That keeps the max 16sqin per cuft recommendation from Fi. If we drop the tuning to 33hz, to keep the same dimensions you drop to 4.2 cuft net and 15.5sqin port area, port would be 5 1/4"W x 14"H and 23.5" inches long. These are pretty quick calcualtions, no bracing and still within Fi specs.

Might want to recalculate those, I fail to see how you can have a 14"h port when the enclosure is only 14"h.

No, the math is right, I'm just a damned goof for saying it was 14", the port height is 12.5". 5.25 times 12.5 is 65.6 divide that by 4.2 (net box size) that equals 15.6sqin per cuft.

like i said earlier all the math is a little quick, but good enough to work by. The enclosure and the tuning are correct, I just wasn't thinking when I mentioned the port height.

Are you doing this by hand or a calculator? I am not getting the same numbers at all. You also can't have a 23.5" port in the enclosure, it will be longer then that because that will end in the corner.

[altoncustomtech 773]

I think I'm going to withdrawl from this one, I trust my calculations but they aren't panning out compared to the online ones. See if someone else can give you some good data.

Sorry dude.

[NB50 206]

Try this.

[drumminian 0]

I think I'm going to withdrawl from this one, I trust my calculations but they aren't panning out compared to the online ones. See if someone else can give you some good data.

Sorry dude.

I trust your calculations and I might use your design to be honest thanks for your help!

[drumminian 0]

Try this.

damn now that works thanks for this man

[altoncustomtech 773]

Yeah I like Bromo's calculator. Me and him have compared each others before, both come out a little different and we each use our own. You should have good luck with the design, don't forget the build log.

[drumminian 0]

I won't forget it I'll post it up as soon as I get the sub next month

[NB50 206]

Yeah I like Bromo's calculator. Me and him have compared each others before, both come out a little different and we each use our own. You should have good luck with the design, don't forget the build log.

LOL, did we I don't even remember. I was getting ready for you to dispute it, but I know its right and geometry agrees with me.

[Cinnabun187 2]

I use the 12volt.com calculator IMO it's retard friendly.

[drumminian 0]

Ahhhhhhhhhhhh so I got the box built yesterday and it's like a half an inch too deep for my truck si I have to grind out some metal to make it fit and there is like bearly any room above the box for the sub to go...

so how do i go about flush mounting the driver? because I dont think the driver will fit with the excursion of the cone moving up and down..

so what do i do...?

[drumminian 0]

anyone?? sub is coming today and want to have this installed asap