is this box calc accurate?

[60ndown 10+ year member]

http://www.accelerator-pedal.com/l-ported-box.htm

Click to read more...

 

[60ndown 10+ year member]

b.u.m.p.!

 

[geonfreaq 10+ year member]

its just blank.

 

[Moe Lester 10+ year member]

seems to me that it doesnt really give enough port area for many high excursion subs.

 

[dbornotdb 10+ year member]

I ran a couple subs through there that I had built boxes for. It was pretty **** close to what I had come up with using winISD and BBP6. The port came out smaller, but not to small as to make a noticable difference in my opinion. Hell, mine could have been to big. I'm not perfect at it.

 

[60ndown 10+ year member]

thanks...............

ill start messin wit it -an buildin! //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[beerman 10+ year member]

seems to me that it doesnt really give enough port area for many high excursion subs.

I can't please everyone. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif
It was designed to make the smallest possible box for a typical daily driver system, given MFR recommendations.

The calculator does hiccup, and I am working on v2.0 to fix the hiccups, among other things.

It will take about 30 seconds to add a checkbox for high SPL, increasing the port area by 33% by changing the minumum port area from 10 square inches per cubic foot to 15 square inches per cubic foot. Would this work, or should I make it even larger?

Ideally, I would take into account woofer parameters and port dimensions to calculate peak port velocity and give the user recommendations if the port is too small or tuning is too low.

Ideally, I would also have all the time in the world. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[Moe Lester 10+ year member]

Hmm, im not sure how much time youve got, but maybe you could program in a few check boxes with different ranges of xmax that could correspond with certain port areas. If the sub has a relatively low xmax, maybe the calculator could figure in 10 sq in per cubic foot. If its got a mid range xmax, maybe give it 15 sq in, and if its got a very high xmax, give it even more.

15 sq in per cube would be pretty good //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[beerman 10+ year member]

We'll go with 15/cube for right now. The hiccups are a bigger priority.

Wanna see it hiccup? Enter one cubic foot enclosure volume, 12" external height, 24" external width, 0.12 cubic foot driver displacement, and 21hz tuning. Note how long the violet board is in relation to the black board. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

I just looked at the code again. The bottom says "rounds to nearest 1/16th" but it actually rounds the measurements to 1/4". Whoops, I just made it easier to build. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[beerman 10+ year member]

V2 is almost ready. Hopefully tonight. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[theCybe 5,000+ posts]

* Keep us updated; I love it.

:cheers:

 

[beerman 10+ year member]

Version Two

 

[norcalSRTrida 10+ year member]

v.2 is lookin great

by NET volume...does that mean volume befor port and sub displacement size?

its after the displacement correct?

 

[beerman 10+ year member]

It rounds off every measurement to the nearest quarter inch as soon as they're made.

I think I could remove the first rounding of port length (until it's time to display) for a touch more accuracy in the violet panel.

But in the grand scheme of things, being off within half a percent in terms of net volume and tuning frequency isn't bad at all, considering that the Vas measurement of a woofer will be off by as much as 20%.

 

[slicks5150 10+ year member]

I think the program has some problems like the port lenght says 16.75 (which is correct) but then it says make it 13.5 inches and only .75 at the bend =14.25"

Net Volume: 2.5 cubic feet

Tuning Frequency: 35 Hz

Port Width: 1.75 inches

Port Area: 23.625 Square Inches

here

****** Port Length: 16.75 inches ******

External Dimensions: 25 wide x 15 tall x 16.75 deep.

Board Dimensions and Quantity

Color Count Width Height

Top and Bottom 2 25 inches 16.75 inches

Red 1 22.5 inches 13.5 inches

Yellow 1 16 inches 13.5 inches

Black 1 23.5 inches 13.5 inches

Green 1 16.75 inches 13.5 inches

and here

****** Teal 1 13.5 inches 13.5 inches ******

******Violet 1 0.75 inches 13.5 inches ******

http://www.accelerator-pedal.com/ported-box.asp

am I missing something here???