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Free Air Subs?

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=55275
Printed Date: May 13, 2024 at 4:19 PM


Topic: Free Air Subs?

Posted By: godd dan it
Subject: Free Air Subs?
Date Posted: May 06, 2005 at 11:57 PM

What are some brands of "free" air subs? I know Pioneer makes some. Anybody else?

Thanks




Replies:

Posted By: LTHLQUICKSILVER
Date Posted: May 07, 2005 at 2:42 AM
JL Audio used to make a version of their W1's as free airs, but not anymore.  You would have to find an older model.

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Muscle Cars Don't Just Look Good, But They Can Sound Good Too...
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Posted By: racer427
Date Posted: May 07, 2005 at 3:23 AM

Infinity Kappa perfects are rated to handle up too 175 watts in a free air configuration.

Chris



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MTX Thunder T6.6 Components:rear fill:
Cadence Q400 4 Channel Mains + rears
Thunder 801D Subs
MTX 1004 10's
Dual 4g wire to rear
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Posted By: bogey
Date Posted: May 07, 2005 at 11:07 AM

LTHLQUICKSILVER wrote:

JL Audio used to make a version of their W1's as free airs, but not anymore.  You would have to find an older model.

I looked up the specs sheet on the W1s and I didn't see anything about freeair. It's possible I missed it though. However, JL did make a 12IB4 that was made specifically for infinite baffle (free air) applications. Perhaps this is what he was thinking of? But they have been off the market for some time now and they rarely, if ever, appear on ebay.

You might also check into Image Dynamics ID series subs and I would second the Infinitys if you are talking about the Kappa Perfect VQ (variable Q), they are free air compatible. The regular Perfect series is not recommended for free air applications.

BTW be sure to have a good seal to separate the front and rear waves. Good luck with your project.





Posted By: kfr01
Date Posted: May 07, 2005 at 11:30 AM
Image Dynamics IDQ series will also work well.

Just remember that power handling is significantly reduced when running free-air.

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New Project: 2003 Pathfinder




Posted By: godd dan it
Date Posted: May 07, 2005 at 11:34 AM

Thanks for the help. Its too bad they dont make the JL's anymore.

I got some more help on another forum. They listed some free air subs for me, but they arent certain on all of them.

Here they are:

Infinity Kappa Perfect 12 VQ
Infinity Kappa Perfect 12d VQ
Infinity Reference 1232w
Infinity Reference 1240w
Blaupunkt PCwb1200
Kicker Comp 03C124
Kicker Comp C124
MTX Audio Road Thunder RT12-04
MTX Audio Thunder4500 T4512-04
Phoenix Gold Octane-R 12

Which subs do you think would give me the most "pound" and is reliable?

Thanks in advance.





Posted By: DYohn
Date Posted: May 07, 2005 at 11:36 AM
"Free Air" (the correct name is Infinite Baffle, or IB) installation seems the simplest to install but in fact is one of the hardest installation methods to make sound good.  ANY woofer can be mounted this way, but only a few actually sound right.  Choose a woofer with a high Qts amd a low Fs.  When installing IB, the front of the woofer must be completely isolated from the back, so you need to seal the mounting area around the woofer frame well and also seal any places where air might leak between the car's interior and the trunk (this means cars with fold-down rear seats are generally a bad candidate for IB mounting.)  The efficiency of the system drops as well as the power handling of the woofer, and there is a severe drop off in frequency response depending on the size of the baffle (the area the speaker is mounted to, like the rear deck.)  A woofer with a sealed power rating of 300 watts RMS will probably only handle 100 watts in IB mounting.  Achievable SPL levels will be much lower than the same speaker mounted in a sealed enclosure, and the overall system Q will be low (meaning the bass may sound "sloppy" or "flabby.")  IB can sound very, very good when done correctly.  It is best suited to vocal, acoustic, jazz or orchestral music and generally not too satisfying for rap, electronica or other "boom" music.

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Posted By: godd dan it
Date Posted: May 07, 2005 at 12:00 PM

Hmm.....very good info DYohn.

Im looking to install a sub in the rear deck of my Mercedes. The gas tank is located in the trunk and is followed by a sheet of metal. So you cant even fold down the rear seats. I had sealed subs in my trunk before and it didnt quite give me enough bass. All the bass has to go through the rear deck which has a hole for the first aid kit and speaker holes. Thats why im interested in IB subs. I think if I seal my trunk good, its possible that ill achieve what im looking for.





Posted By: DYohn
Date Posted: May 07, 2005 at 12:23 PM
I installed a pair of Alumipro Alchemy-FA 12" 8-ohm subs IB in the rear deck of a 300SEL and it sounded excellent.  An older Benz is the perfect candidate for IB mounting.

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Posted By: cdjr
Date Posted: May 07, 2005 at 2:05 PM
Rainbow made an SW300F free-air subs which have been discontinued. The ones that I know of that are still available are the high-end Audiophiles which are SQ oriented, get decently loud but are not SPL subs; and the SoundLines, Rainbow's mid-level subs.

If interested you could contact Jason@arcaudio.com

I bought two 8" and one 10" Rainbow Vanadium subs through him at VERY good price.





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