Change Tuning on This Box
 

Ok, first off it is NOT my design, I am not that good in Sketchup yet.
Second, I have played with some box calcs, and it looks like if I change the 3.5" port width to 5.0", the tuning will change FROM 29 TO 36 as has been suggested to me.

Attachment 22863

http://img.photobucket.com/albums/v7...io/7314_11.jpg

Anyone double check for me? Oh, and I would have to increase the width of the box by 1.5" to retain the volume as well.

that also means that each chamber has to have a 2.5" port at the back. rtaher than the 1.75" it is now. i would also suggest a center divider at least 75% of the way down the port. something like this:


Attachment 22862

Well first, thanks for taking the time to do that.

What purpose do the center divider, and the rear 6" piece serve?

I see the width has been knocked back to 36" plus we have more dividers internally now, so is it just me, or does it look like less internal volume?

Lastly and most importantly, I will go try this on one of the calculators, but is it pretty much at 35Hz now?

Once again, thank you for taking the time!!

John

that is just an example of a center port divider. that blueprint is acually for two 12" Fi SSd's i used to own. if i remember correctly your using eD 13A series subs. if you want i can draw you up something for those woofers. just give me the dimensions you have to work with.

i drew this up for you. 2.25 cubes per chamber @ 34hz. doubble baffled front. 32 some-odd square inches of port per chamber. let me know what you think of it.


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I think I owe you a few coffees or a few pints ;)

Looks like you went to the trouble of going and finding the specs, then did the box. Pretty considerate of you, thank you very much.

This box will be the one then because its exactly what I need :)

Cheers

John

Hey man no problem. I'm only 18, so in 4 months when i'm 19, i'll take you up on the few pints lol. I enjoy designing and building enclosures so this is penuts to me. hopefully you will enjoy it.


Cut Sheet:

Top = 38" x 18 3/4"
Bottom = 38" x 18 3/4"
Front baffle = 16 5/8" x 17 1/2" (4x)
Back = 38" x 17 1/2"
L Side = 16 1/2" x 17 1/2"
R Side = 16 1/2" x 17 1/2"
Port 1 = 14 1/2" x 17 1/2"
Port 2 = 11" x 17 1/2"
Port 3 = 14 1/2" x 17 1/2"
Port 4 = 11" x 17 1/2"
Port 5 = 18" x 17 1/2"

Thanks for the cut specs as well!

Age is just a number (legal ramifications aside of course). You can join the Armed Forces and fight for your country at 18, but not have a pop or two. Silly if you ask me.

Unfortunatly the drinking age is one of those third rail topics that politicians normally stay a hundred miles away from (cant win).

Looks like I will be sending the drawing to one of our fellow members shortly. Before I get flamed, I dont have patience, time, or skill to do a proper job.

Thanks again!

John

^^^ I like your system, jalat. Very decent and you're so young. Usually people your age do not any better. Good stuff!!!

Thanks. I just took the time to read and learn. rather than doing homework, i read pages on acoutics and enclosures... car audio something i really love.

And to john, if you need someone to build the enclosure, my hand is raised... PM me and we'll talk about prices.