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Very important. Stick to the manufactures specs(unless you can use speaker modeling software). I would use AT LEAST minimum spec+polyfill.
 

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Discussion Starter #3
Very important. Stick to the manufactures specs(unless you can use speaker modeling software). I would use AT LEAST minimum spec+polyfill.
I don't know what polyfill is but I'm just going to buy a box. if it says 1 cu ft that means its 1 cu ft, right? Not excluding this polyfill nonsense?
 

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I don't know what polyfill is but I'm just going to buy a box. if it says 1 cu ft that means its 1 cu ft, right? Not excluding this polyfill nonsense?
The box needs to be 1cu ft after your drivers displacement. And Poly fill is not nonsense, it acts as a way to make a smaller box seem larger to the drivers. A very useful tool in adjusting internal volume in enclosures.
 

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I don't know what polyfill is but I'm just going to buy a box. if it says 1 cu ft that means its 1 cu ft, right? Not excluding this polyfill nonsense?
Polyfill is like the stuff inside your average pillow. When used correctly inside a sub enclosure it will make the subs *think* the box is bigger than it really is.
 

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What happens inside the enclosure with poly fill is, as the air moves inside the box, It causes the fibers in the fill to vibrate rapidly. This creates heat inside the box, and effectively slows down the air movement. This creates the effect of a larger internal volume.
 

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so a .75cu ft box + poly fill could meet the minimum for my sub?
It would be close. You want the box as full as you can, but not compressed. Too much fill will not allow it to vibrate and slow the air movement. In other words it would eat up volume, and make it smaller.
 

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General rule is 1lbs bag of fill per 1 cu ft of enclosure. So, about 3/4 bag of fill you can pick up at Walmart cheap.
 

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Discussion Starter #10
General rule is 1lbs bag of fill per 1 cu ft of enclosure. So, about 3/4 bag of fill you can pick up at Walmart cheap.
so would you recommend I get the .75 cu ft box and get 3/4 lbs of poly fill or get a 1cu ft box and get 1lb of poly fill?
 

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so would you recommend I get the .75 cu ft box and get 3/4 lbs of poly fill or get a 1cu ft box and get 1lb of poly fill?
Well if you don't already have the box, I'd get the 1 cu ft. Then you wouldn't need the fill. You could use the fill as a tuning aid, and not to just get you to the minimum required air space. But putting the fill in might help your sub's lower response. Typically subs will perform better on the low side in larger enclosures.
Whereas with the .75, you'd need the fill just to Get you close.
 

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Discussion Starter #13
ok well I haven't got a box yet, and since the max is 1.5 I'll just get a 1cu ft box and get some poly fill?
 

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I'm not a expert, but if you get 1.5cu box, you will be set, unless you are limited to space in your car. I have used that Polly Fill as members are talking bout, and from experience, the sub gets overheated a lot faster. I had Jl Audio 10W7 sub, by using the the materiel to trick my sub and I have cooked the coil. :(
You have to be very careful of how you use it and what you buy.
I would suggest to get a bigger box without the pillow inside of your box.

I have learned my lesson, and now I bought a Morel Ult12", I build the box to specks and called it a day...

Now I don't have to worry about cu. or overheating issues, but that's just my suggestion to you, I may be wrong, members on here have more experience with that stuff. I'm just saying what i have learned from experience..
 

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Sounds good. Don't worry about the poly, It's literally a couple bucks at Walmart. Try the box with out for a while, then try it with a lb. of fill in it and see what ya think. I'm betting you'll like it better in. That's always been my experience anyway.

Best of luck!
 

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I'm not a expert, but if you get 1.5cu box, you will be set, unless you are limited to space in your car. I have used that Polly Fill as they are talking bout, and from experience, the sub gets overheated a lot faster. I Jl Audio 10W7 sub, by using the the materiel to trick my sub. You have to be very careful of how you use it and what you buy.
I would suggest to get a bigger box without the pillow inside of your box.

I have learned my lesson, and when i got my Morel Ult12" i build the box to specks and called it a day...
Did the pole vent get covered or something? What happened?
 

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Get the 1.45 cu ft one.

If you're looking for SQ, most of the time subs will sound better on their larger recommended box. By doing this however, you'd need to lower power accordingly in an attempt to avoid over-excursion.

As an example, Kicker lists all their subs with I think 3 box specs... one is the smallest one, which with the bigger power requirement will sound louder. The second one is a compromise, and the last one is for pure SQ and deep bass.

The box makes the sub sound nice, not the sub by itself.

A cheap sub in the right box will sound better than an expensive sub in a wrong box, most of the time.

http://www.kicker.com/sites/default/files/2007CompVR.pdf

Look at the second page of the PDF, to the right, to see what I'm talking about.
 
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