I got 900 watts going to a Polk 10". It hits

I have 2 JL's in tightly sealed box with only .7 ft^3 space, so I thought this would do
little to improve my sound. Man was I wrong!! I added a 1lb. to each woofer and I
can't believe how much tighter and accurate my subs sound now. Not to mention it
really makes it easier when setting up your front stage. WHY DIDN'T I GET THIS 5
YEARS AGO?!?!?

After replacing my entire Bose premium (?) sound system on my 350Z I started
having a lot of distortion especially from the sub I mounted behind the driver
seat. I started my distortion killing project by spending 2 days on covering the
doors and all around the sub box with Dynamat. I got pretty good results, but I
was not satisfied. Then I started checking the specs for the sub and sub box and
figured my sub box is a little smaller than it is supposed to be comparing the
specs of the sub. I decided to get a bigger custom sub box for my sub and
installed it behind the seat. Again, I had an improvement but there was still
distortion coming out of the sub. I was pretty frustrated after spending about
$300 and days for Dynamat and sub box replacement and I started checking for my
options and I decided to give this polyester stuffing a try. My sub box is about
.7 cubic ft. so I put 1 pound of this stuff in the box and turned the system on.
The result is UNBELIEVABLE!!! Distortion was completely gone and I was able turn
the volume on a lot more than I did before with no distortion from the sub at
all. Don't get me wrong, not only this stuff but everything I did on the system
helped to have a nice system. But this stuff made the biggest difference for me.

I have used this stuff before in sealed subs with great results. So when I needed to take out the hollow-sounding boom in my rear speakers, this stuff really fit the bill. My rear speakers (Dodge Dakota) are mounting in huge empty body spaces, and you could here a terrible booming sound at the resonent frequency of the cavity. I stuffed the cavity with fiberglass insulation in the lower part (they are huge spaces) and topped them off with this stuffing. The result was outstanding! The big boom is gone and all I have is tight clean bass. Now when I add the sub (sealed box on rear seat), it will not have to compete with the big boom - all that's left will be clean bass from 40 Hz to 200 Hz. Highly recommended!

I purchased this stuffing with my 2 subs and my box. I can surely tell you that the bass is
a lot clearer and also hits harder than not having it.

I would recommend this stuff to everyonee who wants that added clarity to their subs!!!!

This makes bass really nice and crisp. Would recommend anyone to buy

i have a sony 10in xplod truck box. when i first hooked it up, it sounded
fairly decent, accurate, and handled my hard rck music well. i decided to put
some filler in it...stuffed it FULL (the filler was coming out of the speaker
cutout! lol) hooked it back up, and the sound was louder, very tight and
accurate, and it doesnt distort as much if at all. i HIGHLY recomend this stuff
to anyone with a sealed box looking for less distortion, higher volume, and
deeper, tighter bass.

I was extremely skeptical when I ordered this stuffing. I went ahead and did it because it was cheap and the two 10's under the back seat of my chevy truck just didn't sound very good. I had previously had the same two subs and the same amp hooked up in my car in a type 2 trunk box and they were awesome, but in the truck they just weren't very loud and seemed to distort way to easily. I ordered two pounds of this stuffing and it surprised me how big it was when it came in. As I started to stuff my box with it, I thought "man, this is rediculous! There's barely enough room in this box for all this stuffing." But I stuffed it all in because my box is two cubic feet and a pound per cubic foot is recomended. I put the subs back in, and man what a difference! I can turn my system up twice as loud as before with no distortion and much deeper, fuller sounding bass. In addition to being able to up the volume, I was able to turn up the gain considerably on my sub amp. This is the cheapest and one of the best improvements I've ever made to my system.

Using polyester fiber stuffing to 'fool' a subwoofer has long been a widely held belief, that honestly, doesn't really make a lot of sense.

I took an 8" subwoofer, and mounted it in a well designed, but slightly too small, enclosure. Inside, I placed the appropriate amount of polyester fiber stuffing.

I used a real time analyzer at 12db/oct resolution. (Most are only 3d/octave, this is a very revealing device.)

And, I played pink noise from 20-100hz. Pink noise is when every octave of sound has the same energy.

I did an A/B test, using this test equipment with and without polyester fiber stuffing.

The result?

When polyester fiber stuffing is added, a small amount of low end response and overall volume is lost. The same result as robbing the enclosure of airspace.

The exact opposite of what it is supposed to do!


Polyfill does have its uses - In a completely square box it can break up standing waves.

Polyester Fiber Stuffing is an old trick used to trick a sub into thinking that the box is larger than it is. I would recommend adding polyester fiber stuffing to sealed boxes although some ported boxes benefit from adding it. For sealed boxes, using the roll or weave polyester fiber stuffing is recommended. For ported boxes, using the rolled polyester fiber stuffing is recommended as the weave will break apart and escape through the port.

Recommended amount is 1lb of polyester fiber stuffing for every cubic feet