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Discussion Starter #1
Has anybody tried this?
I currently have Tang Bands 7" under-hung mid-basses in ~.3^ft sealed kicks, Founteks FR88-EX on-axis @ the A-pillars, and a 12" Phoenix Gold Rsdc in a sealed box in the trunk.
My idea is to eliminate the 12" sub and the 7" mids and replace it with 8" alpine type r's or 6.5" Tang Band neodymium subs and put them in the kicks. The Tang Bands would drop right in, but I would have to cut some more metal to fit the 8's.
The question is: Is it worth it? Will the subs be able to play clean from 300sh Hz down?
 

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So you are asking the Founteks FR88-EX to play 300 and up? It will play but good luck on dynamics and overall sound quality.

Certain subwoofers can play up into midbass frequencies but i will depend on the subwoofer and the enclosure. How well they play is questionable is well.

Can it be done? Yes
Do people do it? Probably not because its setup for failure
 

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Discussion Starter #3
So you are asking the Founteks FR88-EX to play 300 and up? It will play but good luck on dynamics and overall sound quality.
That's where they are currently crossed at. Trust me... there is plenty of dynamics. Tuned properly they are awesome little speakers, and they love 150w @ 8ohms. :D
 

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I ran my pair of AE IB15s and a set of Dyn102 tweeters for a week crossed at 2,200hz and it didn't sound terribly bad, better than most factory systems. No midbass speakers and no midrange speakers. The 15s easily played to 2,200hz and didn't sound that bad but the sound was pretty directional. I had a couple of friends listen to it setup that way and I think disbelief is a good word to describe their reactions. So sure, I think it can be done but the question is why? It's definitely not going to put all of the components in their optimal range.
 

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Discussion Starter #5
The primary reason is to make more room in the trunk. Another reason is that my hatchback has plenty of cabin gain and at lower frequencies it tends to expose the subwoofer, even with my mids crossed at 50hz. :confused:
And of course... Just to try it out and feel the bass coming from the front of the vehicle.
 

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Yes....you can..

I did the same thing with a set of JL 8IB4's in the doors and fountek FR88's in the dash. Xover was lower...about 185 at 18db high pass on the founteks...

It was plenty dynamic...

Understand that if you are really trying to get extension out of the sub and provide a good midbass snap at the same time you will only be able to do so at a limited volume. If you decide to stand on it a bit it will likely muddy up the midbass without a 30hz or higher subsonic filter.

I really liked the setup due to its simplicity, but preferred when I dropped the dedicated sub (12" Soundstream Exact) Then I moved the crossover on the sub to LP of 45-50HZ with the subsonic at 20, It worked out pretty well and the sub blended great...
 

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Has anybody tried this?
I currently have Tang Bands 7" under-hung mid-basses in ~.3^ft sealed kicks, Founteks FR88-EX on-axis @ the A-pillars, and a 12" Phoenix Gold Rsdc in a sealed box in the trunk.
My idea is to eliminate the 12" sub and the 7" mids and replace it with 8" alpine type r's or 6.5" Tang Band neodymium subs and put them in the kicks. The Tang Bands would drop right in, but I would have to cut some more metal to fit the 8's.
The question is: Is it worth it? Will the subs be able to play clean from 300sh Hz down?
I'm not a fan of moving subs up front - it's a lot of hassle, and it's easy to make subs disappear if you tackle a few challenges in the car. Navone wrote the best article on how to do this that I am aware of, sixteen years ago. (It's on his autosound2000 site.)

But I *do* like the idea of using widebanders as tweeters. YES, you lose some efficiency over a conventional tweeter, but there are some small drivers that can take the abuse. (IE, you have to dump more power into 'em to get the same SPL as a conventional tweeter.)

But there are some nice upsides:

  • The Fletcher Munson curves show that we're insanely sensitive to midrange frequencies, so moving the crossover below the midrange fixes a lot of problems
  • A 3" widebander has narrower directivity than a 1" tweeter. Narrowing the directivity can improve soundstaging by reducing reflected energy off of the ceiling, floor, and side windows
  • Thanks to improvements in motor design, there are plenty of 2" and 3" drivers that can do 20khz
All in all, I like it.

I wouldn't pair it with an 8" sub though. Because the directivity of the sub and the 3" woofer do not match, your polar response will go to hell at the crossover point.


I'd probably do a horizontal D'Appolito array, with the widebander in the center, flanked by two more 3" woofers. The dual 3" woofers can move about as much air as a 5" woofer. I'd opt for something like the Fountek in the center, flanked by the Parts Express ND90s. The ND90s cost half as much as the Fountek, have more displacement, and more power handling.

The array is horizontal because that narrows directivity, which is what we want in a car. (At home it's the opposite, because the speakers are generally far from the sidewalls.)

All in all, under a hundred bucks per side, including crossover. I'd do passive of course, since an inductor and a cap are all you need as long as the drivers are very very tightly coupled and you juse a high xover point, where lobing is minimized.
 

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Jim Walter said they use the 8" Alpine as a midbass driver in one of their demo vehicles with great results, but I can't remember where he said they're low-passed at. My concern would be the possibility of the lowend lacking, but everyone has different tastes.
 

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Bessel array
 
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