polyfill?

[SwiftCelGTS 10+ year member]

is this a good idea? i've heard it can make all the difference in the world in how a sub sounds in a box.. it basically makes the sub think the box is bigger correct? i want to put a 12" L7 in a sealed box but its only .88 of airspace. i'm afraid it won't sound very good in a sealed box.

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[azbass 5,000+ posts]

i use it in all my sealed boxes. and works great.

 

[SwiftCelGTS 10+ year member]

but how much?? was it a noticable difference in the sound?

 

[Volenti 10+ year member]

The change you hear after adding fill has little to do with the driver appearing to be in a larger box (this does occur but the audible affects of this are very subtle) and everything to do with the damping properties of fill.

It's similar to how shock absorbers function on a car, if your shocks are worn out the car keeps bouncing for a little bit after it hits a bump, this is what can happen in a sealed box with no fill, adding fill is like fitting a new set of shocks, it makes the sub stop faster after a bass hit instead of ringing.

The end result of this is it lets the sub more accurately track the audio signal, fast and complex bass passages will sound fast and complex, rather than a smeared boomy mess.

Note that some subs and enclosure types have better inherent damping than others and in some cases the effect of fill isn't very noticable.

 

[SwiftCelGTS 10+ year member]

The change you hear after adding fill has little to do with the driver appearing to be in a larger box (this does occur but the audible affects of this are very subtle) and everything to do with the damping properties of fill.
It's similar to how shock absorbers function on a car, if your shocks are worn out the car keeps bouncing for a little bit after it hits a bump, this is what can happen in a sealed box with no fill, adding fill is like fitting a new set of shocks, it makes the sub stop faster after a bass hit instead of ringing.

The end result of this is it lets the sub more accurately track the audio signal, fast and complex bass passages will sound fast and complex, rather than a smeared boomy mess.

Note that some subs and enclosure types have better inherent damping than others and in some cases the effect of fill isn't very noticable.

thank you. so polyfill isn't capable of having a negative effect then correct?

 

[JimJ 5,000+ posts]

The change you hear after adding fill has little to do with the driver appearing to be in a larger box (this does occur but the audible affects of this are very subtle) and everything to do with the damping properties of fill.

You sure about that? //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[dalucifer 10+ year member]

I actually used fiberglass insulation. Works better than poly fill IMO. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[05AztecRed 10+ year member]

Used polyfil in all three of my sealed subs. Sounds good. I put in 1lb. poly per 1 cu. ft.

 

[xxxpower 10+ year member]

can you get this at homedepot or lowes and do you just stuff the box with it

 

[luvinthebass 5,000+ posts]

can you get this at homedepot or lowes and do you just stuff the box with it

rip a pillow up and use that cuz it's POLYFILL well that's what i did

 

[luvinthebass 5,000+ posts]

ghettoness to the xtreme righ there^^^

 

[xxxpower 10+ year member]

and you just stuff the box untill its full of polyfill

 

[luvinthebass 5,000+ posts]

I just put some in the very back of my box and quit adding some till i filled the box half ful and it was deeper bass and no boomyness resonances from a boomy song, so i guess it improved SQ a bit too //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[reneeb7363 10+ year member]

read this page: http://www.moodym.com/audio/fiber.html

(originally referenced in forum: http://www.caraudio.com/forum/showthread.php?t=177860&highlight=poly+fill )

 

[luvinthebass 5,000+ posts]

i've never tried polyfill in a ported box though //content.invisioncic.com/y282845/emoticons/ponder.gif.ec2527b23f1d287b60dcbba54f95edba.gif