Polyfill?

I just bought a box for my JLw6 and the guy working there told me to fill it with polyfill or the cotton stuff they sell for pillows...is he right?  How do I know how much I need? Its a 1.4 cu ft enclosure. Thuan

JL recommends .90 - 1.50 cu ft enclosures. I posted about this and people were telling me to go with 1.25 and someone told me that I should account for actual net space after the sub is installed. So the box is 1.4 but Im not actually getting 1.4 because the magnet and frame takes up some of that...am I on the right track or should I return the box?Thuan

Polyfill will change an enclosure's performance such that there is an increase in apparent enclosure size by as much as 40%.  For subwoofers, standing waves inside the enclosure are not really a problem.  The rule of thumb I use is 1lb per 1cuft of enclosure space.  At that fill rate, standard dacron polyester batting that you can buy at fabric stores will change the enclosure's performance as if it was about 20% larger, and high-performance polyfill such as Parts Express' "Acoustastuff" will change the performance to about 30% larger.  Make sure the polyfill is not up against the speaker's magnet structure, as the heat generated by the speaker can cause it to burn, and make sure it is not blocking your ports (if any.)  Ignore anyone who tells you to use fiberglass house insulation, as this stuff can damage your speakers. Support the12volt.com

So its actually better to have the subwoofer think that its in a larger enclosure then it actually is in? 1.25 cu ft is what other recommended me but I went with 1.40 because the magnet takes up some of this space....is it recommended that I add polyfill to this? Should I find a way to attach the polyfill to the insides of the box or just "throw" it in there?Thuan

I suggest adding 1lb of polyfill to your enclosure.  Mount your speaker and try it.  If it's too boomy, you have too much polyfill, remove the speaker and pull some out.  If it's too punchy or ":tight" sounding, add some more.Support the12volt.com

the best street beat box that we build for the w6v2 series subs is 1.38 cu ft internal with a vent tuning of 38 hz...this is a great box and will produce low to mid 140's with 10 inch w6v2's with the power they take and then a little more2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR

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