tuning a box lower after it was already built?

[jsluss17 10+ year member]

yeah i tried the polyfill and it didnt really do anything it might've changed the tuning a little bit but it seems quieter and doesn't hit as hard. I was just wondering if there was any easy way i could it's not needed really i don't need it though. thanks for all the help

 

[wenn_du_weinst 10+ year member]

change teh way your box is facing until you change the q factor lower

 

[5dollaFtDong]

Maybe you can add additional baffles where the slot opening is. Depending on how much lower you want to tune, you could cut square rings the size of the port, stack them, 2 or 3 high, and use say a 1" roundover bit on the sides to make it look less ghetto.

 

[pro-rabbit 5,000+ posts]

I would still like to know more about the enclosure itself. Height, width, depth, port area, port length. Any pictures would also help. These things are needed before you can really take any of these ideas into consideration to try.

 

[wenn_du_weinst 10+ year member]

wait a second you didn't follow that ******** rule of setting your subsonic 5hz under tuning did you?

 

[Moble Enclosurs 10+ year member]

here is the thing....if you are not utilizing a port that is long enough to cause self compression related to the frequencies of interest, or matching them anyhow, then the compression area will have most of the control over the tuning of the design. So, if you are to try this, the best way is to increase the compression area for lower tuning, that will have more of an effect than making the port longer, which might actually lower output, not just frequency tuning. So, as I said before, jsut doing another design is recommended unless you can utilize the most efficient way to lower tuning in any design that uses a smaller than optimal port volume, which would be to increase compression area. But again, there is always a trade off. So, without knowing the trade off, just design a new one. That is your best bet. Not saying it cannot be done, but doing it the most efficient way in your case might be implausible.

 

[jsluss17 10+ year member]

the box is 22 wide by 19 deep and 11 high. it's supposed to be tuned to 33 hertz i think but i'm not really sure. the batting inside of it just made it a lot worse lol probably not my best idea so im just gonna take it out. will making the actual port thinner do anything? like adding a piece of wood to the side of it on the port to the left side so where the air is coming out?

 

[pro-rabbit 5,000+ posts]

What are the port dims? That enclosure is very small, what do you have in it?

 

[jsluss17 10+ year member]

the long one is 15 3/4 and the L part is 4 inches long. i have an sa-12 in there and it's like the biggest enclosure i could fit in my car (2003 mustang)

 

[pro-rabbit 5,000+ posts]

So what your saying is the outside dims of the enclosure are

22 wide

19 deep

11 high

The port is 20(ish) long

How wide is the port? This box is very very small and should house an 8 or maybe a 10"

 

[dbeez 5,000+ posts]

Bigger box can fit in there its been done.

 

[jsluss17 10+ year member]

the ports 1.75 inches wide. well it's the biggest box i could easily fit in there unless theres better dimensions? it's about 1.75 cubic feet before displacement so it's almost as big as sundown calls for

 

[pro-rabbit 5,000+ posts]

1.97ft3 gross

the port is small, what is the height of the port?

 

[jsluss17 10+ year member]

i think it's probably 9 and a half inches high i would guess

 

[pro-rabbit 5,000+ posts]

Well from what I can tell your port area is small, your enclosure size itself is not to bad at 1.5(ish) after displacements. Perhaps swapping to a precision port would be the best bet for your application.