polyfill in ported box
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=130320
Printed Date: April 27, 2024 at 3:12 PM
Topic: polyfill in ported box
Posted By: 04nata
Subject: polyfill in ported box
Date Posted: January 21, 2012 at 9:18 AM
Is it recommended to use polyfill in ported boxes? I have never asked the question and I suppose it could be attached to the sides so it won't flow out the port. I just always assumed that you only use it in sealed boxes.
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2004 Hyundai Sonata
Kenwood KDC-X599 HU
2-Sundown X-18D4
2-SQ Q4500.1
2-SQ Q90.4
1-Massive DBX4
8-Niche 5.25 mids
8-Niche Tweeters
4-Skar 8" mid-bass
OhioGen 220a alt
OhioGen 350a alt
156.0
Replies:
Posted By: DYohn
Date Posted: January 21, 2012 at 2:20 PM
It can be used in any enclosure. ------------- Support the12volt.com
Posted By: 04nata
Date Posted: January 21, 2012 at 2:51 PM
I guess I should have asked the next question, will it benefit sound quality or levels using it in a ported box?
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2004 Hyundai Sonata
Kenwood KDC-X599 HU
2-Sundown X-18D4
2-SQ Q4500.1
2-SQ Q90.4
1-Massive DBX4
8-Niche 5.25 mids
8-Niche Tweeters
4-Skar 8" mid-bass
OhioGen 220a alt
OhioGen 350a alt
156.0
Posted By: 04nata
Date Posted: January 22, 2012 at 10:53 AM
Anybody have any experience with doing this? Would like some input before I move forward .
-------------
2004 Hyundai Sonata
Kenwood KDC-X599 HU
2-Sundown X-18D4
2-SQ Q4500.1
2-SQ Q90.4
1-Massive DBX4
8-Niche 5.25 mids
8-Niche Tweeters
4-Skar 8" mid-bass
OhioGen 220a alt
OhioGen 350a alt
156.0
Posted By: smgreen20
Date Posted: January 22, 2012 at 10:34 PM
Yes it will apply to ported boxes too. The changes aren't as dramatic as ion sealed boxes, but it does have its place in ported.
Posted By: DYohn
Date Posted: January 23, 2012 at 9:07 AM
If you are building a vented enclosure it is much more important to get the size and port size correct than to worry about adding fill. Just build it correctly and don't worry about fill. ------------- Support the12volt.com
Posted By: 04nata
Date Posted: January 23, 2012 at 9:12 AM
DYohn] wrote:
If you are building a vented enclosure it is much more important to get the size and port size correct than to worry about adding fill. Just build it correctly and don't worry about fill.
No worries, I have the box built and installed already and it sounds great. ( was very concerned that I calculated the ports right), but the thought crossed my mind as I also have 4- 10"s that are sealed, and was just wondering if the polyfill would have an impact on the sound for the ported 15's. ------------- 2004 Hyundai Sonata
Kenwood KDC-X599 HU
2-Sundown X-18D4
2-SQ Q4500.1
2-SQ Q90.4
1-Massive DBX4
8-Niche 5.25 mids
8-Niche Tweeters
4-Skar 8" mid-bass
OhioGen 220a alt
OhioGen 350a alt
156.0
Posted By: jmelton86
Date Posted: January 23, 2012 at 10:28 AM
I used poly fil in the ported box for my 12.
I started with no fill -net volume was about 2.7 cubic feet tuned to about 34Hz with the 2 4x17" aero ports. As expected, it didn't go low enough for me.
I initially wanted a lower tuning, but the aero ports come in a lenth of 17", so I couldn't really add port lenth.
I was told that with heavy stuffing, poly fil adds about 10% of volume to the enclosure. So, I stuffed the box moderately and brought the volume up to right under 3 cubic feet. With the extra 10% of added "volume" from the poly fil, it lowered the tuning to ~32Hz. I love it now.
I trick I was told is to use pantyhose on the inside ends of the ports to keep the poly fil from being blown out of the enclosure. I was told that, when stretched and taped over the end of the port, the pantyhose acts like speaker grill cloth and doesn't affect air flow.
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2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001
Posted By: 04nata
Date Posted: January 23, 2012 at 11:51 AM
That's great information, who'da thunk that adding something into the airspace would actually create MORE airspace, may sound wierd, but "I'm stuffin' mine tonight !!!!!!!!!!!!!!!!!!!"
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2004 Hyundai Sonata
Kenwood KDC-X599 HU
2-Sundown X-18D4
2-SQ Q4500.1
2-SQ Q90.4
1-Massive DBX4
8-Niche 5.25 mids
8-Niche Tweeters
4-Skar 8" mid-bass
OhioGen 220a alt
OhioGen 350a alt
156.0
Posted By: haemphyst
Date Posted: January 23, 2012 at 2:57 PM
It doesn't make it larger... If you add something to a volume, it CAN'T be larger afterwards, can it?
It makes it ACOUSTICALLY larger, by extending the acoustic path to the boundaries of the enclosure, as well as absorbing energies injected into the space.
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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: jmelton86
Date Posted: January 23, 2012 at 4:26 PM
That's neat. I'm going to have to read up on this some more.
I was told, by someone who otherwise knows nothing about audio, that the poly fil fibers vibrate at a high rate of speed causing the air in the enclosure to warm up causing added "volume".
-------------
2013 Kia Rio -90a alternator
DDX470HD GTO14001 GTO1014D (x3)
Big3 in 1/0G
1/0G to GTO14001
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