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Best way to decrease the internal volume of a sealed speaker?

I have a very fine sealed 0.75 cu foot cabinet that I would like to reduce the internal volume to about to about 0.45-0.65 cu feet. There is limited space to add things like bricks, pavers etc inside.
I am thinking of using some plastic containers with lids glued to the inside cabinet. Should they be filled with sand?

ozzy


128x128ozzy
cliffkhz
47 posts
 

As I see it, you want to take out between 0.10 to 0.30 cu.ft.

Use a cu.ft. to cu.in. calculator to convert. I would use 2x4s.

Start out with the smaller piece of wood then adding more blocks until you get your desired sound. Use double sided foam tape (3M @ Home Depot) that way you can add or remove the blocks.

I'v built quite a few speakers an using the calculator helps greatly in figuring out interior Cu.Ft. or Inches.

Hope this helps.

theaudiotweak
2,774 posts
 
Ozzy

Seal the sawdust and glue with something...varnish the inside a couple of coats or so.Tom
ozzy's avatar
ozzy OP
7,239 posts
 
toddverrone, cliffkhz, theaudiotweak,

Thank you for the help and the posts.
The woofer I will be using will be located very close to the bottom of the cabinet. Because of this it will be near impossible to place wood at the bottom of the cabinet.

The upper inside top appears to be the best place for any type of cabinet internal volume reduction.
So, at this point, I am first going to try the Styrofoam route. I think I can glue a chunk of it to the inside top. If this rattles or comes loose then the next plan would be to change the front baffle so that the woofer can be raised up and allow the installation of wood or bricks etc. at the bottom.
The front baffle is 1" thick and cutting openings again for the ribbon tweeter and the woofer is not an easy task. 

ozzy

ozzy's avatar
ozzy OP
7,239 posts
 
Well I've changed my mind about the Styrofoam.
It looks like I can install some 2x4's pieces inside. I have some 2x4 material made out of Trex that seems to be quite dense an much heavier than a regular 2x4.

ozzy
ozzy's avatar
ozzy OP
7,239 posts
 
I just installed the Trex 2x4's.
I installed (2) of them 18" long on each long side placed in the middle of the cabinet.
I figure with that wood my cabinets math out to be .62 cu feet. I already can tell the difference with tighter and deeper bass. The woofers will probably need some time to break in fully, but at this point I am very happy.

I really want to thank you all for the ideas and support. 

ozzy
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