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blowthemup
12-30-2007, 08:51 PM
How do you calculate displacement for bracing and the driver? Im using this calculator http://www.reaudio.com/speaker_box/LPort_Box_Calc.html. When I add bracing and the driver thats gonna raise the tuned frequency. If I want the final frequency to be 33 should I change the port size to make the tuned frequency a little lower, so after adding the driver and bracing I will have the desired tuned frequency?

SeanDub
12-30-2007, 08:52 PM
Just add to the net volume of the box, not the port volume. Then adjust the port length to obtain the desired tuning with the new net volume.

blowthemup
12-30-2007, 08:58 PM
I want to make a custom fb top plate with the sub firing up (facing the top of the trunk) and the port firing from the side of the box ( toward the back of the trunk/car). The port will be an L port. Is that ok or a bad design.

BuckyBoy
12-30-2007, 09:01 PM
sub up, port back. lots of people use that design.

blowthemup
12-30-2007, 09:06 PM
When bracing the ring in place to do the fiber glassing, are those braces spose to have structal support or are they just temporary to hold the ring in place?

blowthemup
12-30-2007, 09:57 PM
Anyone know? Also, would an aero port sound better than a slot port? Box will be about 4 cu.ft.

TWOJZ
12-30-2007, 10:38 PM
Just add to the net volume of the box, not the port volume. Then adjust the port length to obtain the desired tuning with the new net volume.

no, dont adjust the port length, or else, when the bracing and woofer displacement are added to the volume, to bring the volume back to what you required, the tuning will be wrong.

TWOJZ
12-30-2007, 10:39 PM
When bracing the ring in place to do the fiber glassing, are those braces spose to have structal support or are they just temporary to hold the ring in place?

structural is good...

blowthemup
12-30-2007, 10:47 PM
What about aero port compared to slot port? Whats going to go sound better, which would be louder?

TWOJZ
12-30-2007, 10:48 PM
What about aero port compared to slot port? Whats going to go sound better, which would be louder?

try them both and see? :p

blowthemup
12-30-2007, 10:52 PM
I would but I dont really have the money to be building more than one box. I'm gonna be building my first box and the top plate is gonna be custom fb, where the rest will be mdf. The aero port would be much easier cause I can just cut a whole on a side and put the port in.

TWOJZ
12-30-2007, 10:53 PM
use the Aero then :)

blowthemup
12-30-2007, 11:02 PM
Whats a good prgram to design a box?

Dtrickz
12-31-2007, 12:25 AM
a slot port would probably work for ya. The dowels used to hold the sub ring up while fiberglassing isn't really meant for strength, just there to hold the ring in place while the first layers of fiberglass are laid down

blowthemup
12-31-2007, 12:33 AM
Do you end up taking them out or do you just leave them in? My box can only be 16 inches high so i'm trying to thigure out a cool design. Kind of wanted the sub firing up or at an upward angle. That would mean the top plate would be custom fb for a cool design. That would mean the port would have to be on the bottom and thats leaving me with very litte room for being creative. I'm still thinking though.