View Full Version : Will adding bracing in a ported box raise or lower the tuning frequency?
bubbagumper6
06-06-2009, 11:42 AM
Just wondering, I'd like to play around with the tuning frequency of my box, if I add some mdf blocks into the main chamber to lower the total volume, will that raise or lower the tuning frequency?
JBLCAMRY
06-06-2009, 11:43 AM
raise
grimreper912003
06-06-2009, 11:43 AM
It will raise your tunning. The less airspace, the longer your port needs to be if you have the same port area.
bubbagumper6
06-06-2009, 11:45 AM
ok thanks, is there any easy way to lower the tuning?
skmfkr
06-06-2009, 11:49 AM
make the port longer. use aeros and use a longer port
bubbagumper6
06-06-2009, 11:52 AM
Box is already built, adding bracing is easy, I don't really want to modify the box at all. I was just looking for some easy ways to play with the tuning frequency to see what sounds best, but if I can't do that without modifying the box, then I'll just leave it alone...
grimreper912003
06-06-2009, 11:55 AM
Try changing your port area by adding wood to it.
bubbagumper6
06-06-2009, 11:57 AM
It's slot ported, and there's one bend in it. Will it matter if I only change the port area in the main slot? It would but pretty hard to get a piece of wood into the back port area...
Here's the specs:
http://img193.imageshack.us/img193/5817/12588128.jpg
thehardknoxlife
06-06-2009, 12:02 PM
Make another box 1.5x too big with aeros, then you'll have all the flexibility you need.
bubbagumper6
06-06-2009, 12:05 PM
nope, don't want to build another one. This isn't really a need. I'm fine with leaving it the way it is. But if it was as easy as adding bracing or something similar I was going to play around with the tuning fq, for fun.
ngsm13
06-06-2009, 12:06 PM
Stuff it with poly-fill.
One pound per cubic foot.
NG
bubbagumper6
06-06-2009, 12:08 PM
I was thinking that, but I wasn't sure if poly-fill would actually alter the tuning fq. And I didn't want to suggest it and sound like an idiot :P
ngsm13
06-06-2009, 12:38 PM
Poly-fill can yield results similar up to ~20% gain in internal volume of the enclosure. Which would have the effect of lowering the tuning.
nG
Anniku989
06-06-2009, 12:50 PM
Use something that doesn't take much airspace (not wood), either get some all-thread or aluminum angle iron (for the corners) and use that
Hybrid90accord
06-08-2009, 03:48 PM
have u though about adding fiberglass to the inside of the box to make it a lil stronger???? its an idea
iamamp3pimp
06-08-2009, 03:50 PM
raise.
iamamp3pimp
06-08-2009, 03:57 PM
it will raise it less than a tenth of a HZ
its really not a big deal.
Lakota
06-08-2009, 04:04 PM
Why do you want to brace such a little box?
iamamp3pimp
06-08-2009, 05:02 PM
i put a blanket in mine to drop tuning one day
bubbagumper6
06-08-2009, 05:16 PM
Why do you want to brace such a little box?
Did you read my first post? I don't care about bracing it, I just wanted to play around with the tuning frequency.
Lakota
06-08-2009, 05:30 PM
You will have to make some pretty significant changes in the volume to have a big effect on the tuning. It's pretty much a waste of time, imo.
bubbagumper6
06-08-2009, 05:32 PM
You will have to make some pretty significant changes in the volume to have a big effect on the tuning. It's pretty much a waste of time, imo.
not really...I wasn't talking about changing the frequency by 20hz, just changing it a 1 or 2hz at a time isn't all that hard...besides, I wasn't really looking for any more input, this thread is a few days old, and I considered it dead.