I have some left over sound deadening Fatmat, and was thinking about doing the inside of the box. Was wondering if anyone else has done this to a sub box? and if you have what difference did it make if any?

p.s. I have a Type-X 10" and a soon to upgrade my 605 to a 1005

 

Dont do that!!! You want the bass wave inside a box to resonate inside the box. Depending on the size of your box and what your sub requires some poly-fill inside could improve the sound. Loosly filling a box with polyfill will slow down the bass wave making the sub act as if it were in a bigger box...aka a little louder and a little deeper bass.

 

i could be wrong, but why do you want bass wavse to go inside the sub box? is that what causes standing waves in a relatievly square enclosure?

i have been taught that dampening the inside the box, though not neccessary, does help, it helps further prevent the subbox itself from vibrating and flexing, causing un wanted boominess and distortion...

just my two cents...

etiher way, if its a well built box, i doubt you wil hear a difference, so save the stuff for AFTER you install the sub box and find the rattles int he car

b

 

My box is well built, i already have the sound deadening on the outside of the box aready.

Ill be doing the rattle hunt this weekend, plus tuning my audio system with my new handheld RTA.

I think i wont do it. Just wanted to get some feed back, thanks

 

Wrong. You want a certain volume of air acting as a constant air spring for proper performance. You do not want standing waves or resonances, as these can and will be heard as distortion.

You got it right on the polyfill part though.

 

I build A fiberglass corner sub box really quickly a while back, not the sturdiest i've made....I deadened the inside and it made a significant difference in the sound. But if you have an mdf box or very thick fg box deadening the inside should not be neccessary.

 

jim i feel awesome that we agree on things this time :P jk

 

Good home speakers are inner wall lined with thermal insulation
to prevent hard hits from making the speaker knock inside.
We could duplicate this by 3M spray adhering thin (say 1")
soft thermal fiber insulation on the inner walls of the
sealed enclosure until the displacement matches the sub spec.
Net volume = (L-1")x(H-1")x(W-1")-Sub displacement.
Granted this is more effort than stuffing a pillow in it, but
keeping a large air pocket around the sub will maximize clarity.
Thoughts?

 

There are circular fat mat type pads designed to go directly behind the mid-bass drivers in the doors for sale so someone must think they're doing something. Try it out and see what you get? You're going to play hell peeling off the stuff if you don't like the sound though.

I am of the opinion that there's way too much "magic" going on in the audio business making people who listen to music with their wallets money disapear. If I can't hear it I'm not paying for it.

 

The enclosure itself should NOT be "live" - for example the $2500+ home theater subs I used to sell - you could sit on the thing during the intro to Two Towers (the Balrog re-hash scene) and hardly feel a thing... Meanwhile the room would be pounding with action.

This, however, is accomplished through a matrix-braced cabinet made with the proper materials and engineering, not a few extra sheets of Dynamat.

Sorry....