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hdave
04-23-2006, 03:46 PM
hello, i made my first sealed box ever (made a few ported ones before though)
anyways, the INTERNAL dimensions are 13.5 x 34.5 x 4, so its about 1.07 cubic ft

i was just wondering, how much polyfill should i put in it?

this is for an oz matrix elite 12 dual 4, powered by an arc kar 1000.2t @ 2 ohms (approx 900 rms)

i listen to mostly rap, a bit of reggae, and hardly anything else

hofulstrof
04-23-2006, 03:56 PM
none? by adding about 1.5lbs per cf it will make the sub see a box which is about 25% bigger

Ingleside
04-23-2006, 04:12 PM
wait... its only 4 inches deep?

or am i missing something here....

hofulstrof
04-23-2006, 04:57 PM
could be mounting the subs inverted seeings as his subs need a mounting depth of over 7"

thai_creeper
04-23-2006, 05:02 PM
inverted, isn't 4 inches deep still really small? or do some people have enclosures that small

hofulstrof
04-23-2006, 05:05 PM
aparently hdave does pics?

Ingleside
04-23-2006, 05:06 PM
ahh, im still waking up... =(

hdave
04-24-2006, 12:02 AM
ill post pics tomorrow.
yep inverse mounted

the sub is like 8" long itself

hdave
04-24-2006, 06:45 PM
1. how much polyfill should i use?
2. where do i get polyfill from?


okay here are a couple pics of the box (1.07 cu.ft sealed)
the sub will be inverse mounted (oz matrix elite 12)
and a pic of the amp powering it (arc kar 1000.2t)

http://www.uoguelph.ca/~hdave/box1.jpg
http://www.uoguelph.ca/~hdave/box2.jpg
http://www.uoguelph.ca/~hdave/me12.41.jpg
http://www.uoguelph.ca/~hdave/me12.42.jpg
http://www.uoguelph.ca/~hdave/me12.43.jpg
http://www.uoguelph.ca/~hdave/amp1.jpg

hofulstrof
04-24-2006, 08:49 PM
looking good man. you should be able to find polyfill at the closest wallmart. is in not the same stuff they use in cheap pillows? and as for how much it depends on how much larger you want your box to seem

hdave
04-25-2006, 10:16 AM
im not exactly sure.. i listen to mostly rap and some reggae, and usually not much more than that

what amount of polyphill do u guys suggest?

j3bus2k3
04-25-2006, 10:20 AM
I dont know a rule of thumb off the top of my head but 1 lb is what I've heard people suggest....dunno if that will work for your good though...

AlpineUser
04-25-2006, 06:10 PM
1 pound per cubic foot is what Ultimate Electronics told me...but if ur inverting the subs i dont know if u need it or not

squeak9798
04-25-2006, 06:14 PM
There is no right or wrong answer here.

A properly sized enclosure shouldn't need any polyfill at all.

Other than that, play around with the amount of polyfill and see if you like/don't like the changes in sound. Keep in mind the changes will be small, so don't expect huge dramatic changes.

Buy a couple pounds of the pillow stuffing at Walmart. Start with no polyfill and listen. Try putting in 1lbs and listen again. Try adding .5lbs more and listen again. If you don't like it, take some or all of it back out.

hdave
04-25-2006, 06:30 PM
thanks a lot

what sealed volume would you guys reccomend for this sub?

squeak9798
04-25-2006, 06:34 PM
OZ recommends 1cuft...so your enclosure is pretty spot on already.

http://ozaudio.com/pdf/oz/Matrix%20Elite%20Manual.pdf