Can I use a prefab ported box and use poly fill to tune it?

[joem1cha3l 10+ year member]

Please dont laugh guys, but would I be able to buy a prefab ported box for my 12" Type R and stuff it with poly fill to optimize its potential? What do you guys think? Please let me know.

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[96civ 10+ year member]

IIRC, polyfill doesn't affect any parameter of the box, except it dampens the rear wave. So it will do nothing to the tuning of a ported box.

 

[joem1cha3l 10+ year member]

so it wont make my sub sound as good as a larger box?

 

[guting 10+ year member]

LOL! nah it doesnt work like what your thinking.

 

[BOOKER 10+ year member]

There is nothing wrong with prefab boxes if they are well built and within recommended size.//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Give it a try and find out by yourself how it sounds.

//content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

 

[WantedIsHere]

you guys shouldnt be saying it wont change the tuning... Fact it will change the tuning. anythinginside a box that takes up space will change tuning. Granted poly fill doesnt really have a ton of mass so it might not be the best thing to use... To answer the question for the OP you can add wood or another dense material and change the tuning more effectively. I personally couldnt tell you what effect the poly would have on a ported box as i have never done it but i would just build a correct sized box or buy a correct sized box...

 

[guting 10+ year member]

you guys shouldnt be saying it wont change the tuning... Fact it will change the tuning. anythinginside a box that takes up space will change tuning. Granted poly fill doesnt really have a ton of mass so it might not be the best thing to use... To answer the question for the OP you can add wood or another dense material and change the tuning more effectively. I personally couldnt tell you what effect the poly would have on a ported box as i have never done it but i would just build a correct sized box or buy a correct sized box...

why raise the tuning?//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[WantedIsHere]

i dont know maybe he doesnt want it tuned the way it comes... ask the op i just answered his question and said not to post false info

 

[Volenti 10+ year member]

As others have said fill will have a damping effect on the enclosure, this may make a poorly tuned enclosure sound better by virtue of damping the very resonance that makes ported boxes work, but it's no substitute for a correctly designed enclosure.

 

[azbass 5,000+ posts]

nonononononononononononononononononononononononono

 

[Ignatowski 5,000+ posts]

you cant use poly in a ported box,the stuff will get blown the fvck out and defeats the entire reason for going ported in the first place silly..im under the assumtion you havent heard a good ported box

 

[newusername 10+ year member]

As others have said fill will have a damping effect on the enclosure, this may make a poorly tuned enclosure sound better by virtue of damping the very resonance that makes ported boxes work, but it's no substitute for a correctly designed enclosure.

With the appropriate amount of polyfill, it actually performs the exact same way a "correctly designed enclosure" will.

Polyfill is perfectly usable in a ported enclosure. If you're having problems with it blowing out, either move it further away from the port or staple/glue it down.

 

[audioholic 5,000+ posts]

you cant use poly in a ported box,the stuff will get blown the fvck out and defeats the entire reason for going ported in the first place silly..im under the assumtion you havent heard a good ported box

Incorrect. Many people use poly in their ported boxes, you just have to put a screen over the port.
Poly wont make any changes drastic enough for you to be able to 'tune' the box the way you want.

 

[azbass 5,000+ posts]

you should Not even need to use polyfill in a normal vented box anyway actually.

 

[bass_lover1 10+ year member]

why raise the tuning?//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

In a ported enclosure, keeping port length and area the same, less airspace will raise your tuning frequency.

you cant use poly in a ported box,the stuff will get blown the fvck out and defeats the entire reason for going ported in the first place silly..im under the assumtion you havent heard a good ported box

Yes you can, the air inside the port doesn't move how you're thinking it does. The air inside the port with the given area and length, has a mass which is how you "tune" a ported box, think of this air as something similar to a passive radiator, you use mass to achieve a desired frequency, with that said, the air resonates in a similar fashion as a PR, both have similar effects on output.

The air you feel at the end of the port isn't being "blown out" of the box, it's the air outside of the port that is being affected by the resonations of the air that is inside. Take your hand and hold it over the port while the driver is playing, you feel the air being moved around it, now stick your hand in the port and you no longer have that feeling, if you do, at a much lesser extent.

Yes, the resonations and vibrations caused by the driver can cause the polyfill to become dislodged and move, but in any enclosure I wouldn't advise to leaving it unsecured, glue it staple it, whatever but you can use it.

With all this being said, a properly built ported enclosure built for your goals, will surpass any prefab box, most prefab ported boxes will not give you airspace, port area, length, or tuning frequency, which isn't really something I'd want anything to do with.