View Full Version : Sealed Box question

01-09-2008, 02:02 PM
I am making a sealed box for my 12" Type R and have a question. The box is ~0.95 cu. ft. gross (0.88 cu. ft. net) volume, slanted where the sub will mount, 14" wide x 14" deep x 14" tall side/10" short side. It will be run by a Cadence TXA-750D (600w RMS / 1200w Max) running at 1ohm (dual 2ohm sub). My goal is very much SQ.

I have heard that it is a decent idea to put some sort of foam on the inside of these boxes opposite the speaker. Should I put some Ensolite foam on the back panel? Or will this take away from the performance/"reduce" the enclosure volume like polyfill does?


01-09-2008, 06:05 PM
Since when does polyfil reduce enclosure volume or hurt performance? Polyfil will lower the alignment (like a larger box does) and will reduce upper order harmonics' standing waves. The foam will help with it as well but the difference is slight.

01-09-2008, 06:06 PM
My goal is very much SQ.

May I ask why you went with a Type R, then?

I can think of a bunch of other drivers that are that price or cheaper that'll sound better in a sealed environment...

01-09-2008, 07:07 PM
I have heard that Polyfil simulates reducing the size of a box. I will have to check my sources a bit better next time. But since I have a few square feet of Ensolite left, I will use some inside this box.

Jim, I haven't built a box or system or anything before, so I went on price and some basic reviews. Could you make some suggestions?

01-09-2008, 07:09 PM
Polyfill does exactly the opposite, it simulates a larger enclosure. It is used primarily when box size is kept small due to space issues, or preference.

01-10-2008, 12:25 AM
type R, SQ, :crazy:

01-10-2008, 02:49 AM
I would personally sell the sub and go a different route if you are truely looking for SQ, and want to be happy when its all said and done

01-10-2008, 02:53 AM
polyfil makes a box "seem" 10-20% larger its good if u accidentally made box too small or have limited space

01-10-2008, 01:35 PM
To all that say "get something else" - make suggestions! I am not looking to spend a ton of money on this thing, I think this sub was $112 shipped. So, suggest something for either 375w at 2ohm or 600w at 1ohm.

01-10-2008, 01:59 PM
Try the Dayton RS series.