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View Full Version : This Box Design is Correct Right???



btdickey99
02-03-2008, 02:03 AM
I have drawn up my box plans and wanting to make sure I have calculated correctly.

The box volume is approx 3.0cu ft(after .23 cu ft driver displacement) w/ .79 cu ft(1363in) of port

port length=23.5"

and the box tuned to @ 42

and here are the pics...sorry they were quickly done and didnt feel like Downloading a program

http://i262.photobucket.com/albums/ii83/btdickey99/boxdim.jpg



I just want to make sure I did everything correct, and if now where do I stand?

btdickey99
02-03-2008, 02:23 AM
ttt anyone?

btdickey99
02-03-2008, 02:54 AM
word up up up

JimJ
02-03-2008, 02:55 AM
42Hz is way too high for anything but a competition-only enclosure, IMO...

btdickey99
02-03-2008, 02:56 AM
42Hz is way too high for anything but a competition-only enclosure, IMO...

yes I kno :crap:, I would like to be @ 36, but not finding the best way with a box this size....maybe slimmer port?

btdickey99
02-03-2008, 02:57 AM
and I think I messed up on port length, making it to tuning @ 39....which will have to be enough for right now

dragnix
02-03-2008, 03:05 AM
doesn't look like you have a port :p:

btdickey99
02-03-2008, 03:14 AM
doesn't look like you have a port :p:

LOL thanks for that.....

<-----FAILED with drawing

JBLCAMRY
02-03-2008, 10:16 AM
LOL thanks for that.....

<-----FAILED with drawing

pm me and ill help you out

Immacomputer
02-03-2008, 11:11 AM
2.88 tuned to 38hz is what I found. Your port length is more like 30", not 23.5". Port length is NOT the length of the wood used as the port. Somehow you randomed your way to getting pretty close to the specs you wanted... I'm impressed.

btdickey99
02-03-2008, 01:08 PM
2.88 tuned to 38hz is what I found. Your port length is more like 30", not 23.5". Port length is NOT the length of the wood used as the port. Somehow you randomed your way to getting pretty close to the specs you wanted... I'm impressed.

my original instict was the oirt length of bth boards...then after looking at it p here I realized I didnt factor in the fact of half was between the open area and the the 4" over towards the other port.

^^^hopefully this was understood, and I got the volum close by just subtracting both the port areas.....

thanks for the help

Immacomputer
02-03-2008, 01:17 PM
That's really not a good way to subtract the port volume.

If you want to know the exact volume, either use the inside dimensions that exclude the port or draw it up in a program like sketchup and let it calculate it for you. Check out the picture below for an example.

http://i27.tinypic.com/14tseo6.png

After you click the "selection" tab, it will calculate the area for the given section you have selected. From there, multiply by the height in inches and then divide by 12 (because it gives square feet not square inches so you don't have to divide by 12^3). That will give you a much more exact volume. Also note that the actual port length is shown by the black line that runs along the center of the port. The summation of the black lines is the actual port length.

btdickey99
02-03-2008, 01:18 PM
what program is that, that your using???

Immacomputer
02-03-2008, 01:38 PM
Google Sketchup... I said that already.