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bmk6795
08-05-2013, 09:35 PM
The dims for my box are 17H x 32W x 22D. The port dims are 15.5H x 4W x 28L. Now what im really needing help with is measuring the port walls. From my understanding to build this correctly, for the center line, it'd be, 22 - .75 (for the back wall) - 2 (for half the port width). Which comes to 19.25. Then take 28 (port length) - 19.25 - .75 (wall again) - 2 (half port width) = 6. So the centerline would be 19.25" from front to back, and 6" from right to left, correct? Then to calculate the actual port wall you'd take the 19.25 - 2 (other half of the port width) giving you 17.25. THen take 28 - 17.25 - 2 (other half of port width) = 8.75. So the actual port wall would be 17.25" from front to back, and 8.75" from right to left correct? If im wrong here someone please point me in the right direction, this is bugging the **** outta me, lol. Thanks for any help.

bmk6795
08-05-2013, 10:16 PM
NASTY08IMPALA ; DukeNut ;

loudlittlefvkus
08-05-2013, 10:42 PM
that sounds right, i didnt exactly do all the math though.. but what helps a lot is to get a visual, draw it out or something. and you want the 'middle' of the port to be the port length.
this guy does a really good job at explaining it all, and if you wanted to sketch it out its a great tutorial.
How to Design a Subwoofer Box in Google ( Trimble ) Sketchup - Car Audio Fabrication CAF - YouTube (http://www.youtube.com/watch?v=ZCeUB63Sjks)

loudlittlefvkus
08-05-2013, 10:43 PM
that sounds right, i didnt exactly do all the math though.. but what helps a lot is to get a visual, draw it out or something. and you want the 'middle' of the port to be the port length.
this guy does a really good job at explaining it all, and if you wanted to sketch it out its a great tutorial.
How to Design a Subwoofer Box in Google ( Trimble ) Sketchup - Car Audio Fabrication CAF - YouTube (http://www.youtube.com/watch?v=ZCeUB63Sjks)

bmk6795
08-05-2013, 11:17 PM
that sounds right, i didnt exactly do all the math though.. but what helps a lot is to get a visual, draw it out or something. and you want the 'middle' of the port to be the port length.
this guy does a really good job at explaining it all, and if you wanted to sketch it out its a great tutorial.
How to Design a Subwoofer Box in Google ( Trimble ) Sketchup - Car Audio Fabrication CAF - YouTube (http://www.youtube.com/watch?v=ZCeUB63Sjks)

Ive got a design for it in the making, just wanted to make sure the port lengths were correct before designing it, again, lol. Will design it and post up the results, thanks for the help man.

Buck
08-05-2013, 11:24 PM
Drawing it up is the best thing. Keep in mind every calculator may have a set end correction factor, like if a port is slot vs. just a square port say in the bottom of the box then their port lengths will be different. But at the same time, you have less consequence on port length because usually it's just a couple of inches of error, so depending where you're trying to tune, you're still not terribly far off.

Buck
08-05-2013, 11:24 PM
Drawing it up is the best thing. Keep in mind every calculator may have a set end correction factor, like if a port is slot vs. just a square port say in the bottom of the box then their port lengths will be different. But at the same time, you have less consequence on port length because usually it's just a couple of inches of error, so depending where you're trying to tune, you're still not terribly far off.

bmk6795
08-05-2013, 11:52 PM
Ok the box specs changed a bit as i didnt realize the box was not what i wanted. New box dims are 17H x 33W x 23D. Port dims are 15.5H x 4W x 29L. So the center line is now 23 -.75 - 2 = 20.25 from front to back, the side is 29 - 20.25 - .75 = 6 from right to left. The actual port wall is now 20.25 - 2 = 18.25 from front to back, and 29 - 18.25 -2 = 8.75 from right to left. Sound about right? I did a sketch up and fixed torres, hopefully this looks right :D

http://i1269.photobucket.com/albums/jj588/bmk6795/Boxspecs_zps742a1da2.png (http://s1269.photobucket.com/user/bmk6795/media/Boxspecs_zps742a1da2.png.html)

http://i1269.photobucket.com/albums/jj588/bmk6795/Boxsketch_zps6fd652e0.png (http://s1269.photobucket.com/user/bmk6795/media/Boxsketch_zps6fd652e0.png.html)

Port from the front:

http://i1269.photobucket.com/albums/jj588/bmk6795/Portview_zpsd7fbcbb7.png (http://s1269.photobucket.com/user/bmk6795/media/Portview_zpsd7fbcbb7.png.html)

Port from the side:

http://i1269.photobucket.com/albums/jj588/bmk6795/Portsideview_zpsc301db3b.png (http://s1269.photobucket.com/user/bmk6795/media/Portsideview_zpsc301db3b.png.html)

The port measures 4" from the top of the box and the side of the box. port wall from front to back is 18.25" and from side to side is 8.75. Lemme know if anything is off. I do plan to do round overs and ill fix the top of the box after i make sure the design is correct.
loudlittlefvkus ; Thanks for looking at this man.

bmk6795
08-05-2013, 11:54 PM
Drawing it up is the best thing. Keep in mind every calculator may have a set end correction factor, like if a port is slot vs. just a square port say in the bottom of the box then their port lengths will be different. But at the same time, you have less consequence on port length because usually it's just a couple of inches of error, so depending where you're trying to tune, you're still not terribly far off.

That makes sense. Also would explain why torres "physical port length" doesnt match mine. I drew it up and posted it up, maybe you could take a look at it as well? :D

bmk6795
08-06-2013, 09:32 AM
bump

bmk6795
08-06-2013, 12:34 PM
up top

bmk6795
08-06-2013, 06:51 PM
bump

bmk6795
08-06-2013, 09:59 PM
Someone help me out here :(