My setup is strictly SPL. It's not my daily driver(well, until my truck died on me). The box was designed by Kicker, and built/installed by my sponsor, S&M Audio. The resonant frequency of my Cougar is aprox. 34hz. Since the box was in the hatch(not a wall) behind the C pillar, the rf didn't change. I'm hurting myself with the current amp. I need good, clean power.. And I need to get up to the RMS of those subs.

When I say it falls off at 50 hz. It doesn't stop all together, it's just not as predominant as the 30-45 hz range. And trust me, it plays plenty low... I pulled a 145db at 26 hz. Don't suffer from port noise at all either. The way the box is designed, the port comes out right where the rear hatch glass connects to the bottom hatch lid. Techies at Mark Antony claimed this would help with the phasing(???) I have no idea about that.

I'm pretty happy with 150 db off 2 subs, 500 watts a piece, and no Dynamat. I'm sure my deck is only a 4V preout deck too....

Shon


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2000 Mercury Cougar Special Edition
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http://www.geocities.com/bustatail.geo/smith.html

 

I'd keep it hooked up the way you have it right now if they're 2 ohm. Are they 2 ohm or 4 ohm DVC's?



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2000 Mercury Cougar Special Edition
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http://www.geocities.com/bustatail.geo/smith.html

 

Mine are 4ohm DVCs. And separated chambers on the box. I always do that. Sounds great either way, but I'm just curious about stress on the amp. I've never been a fan of bridging due to the overheating potential.

In retrospect, I've heard those amps aren't recommended for running 2ohm loads, yet it says right in the owners manual that they can. Just not below 2ohms. Thoughts...

 

Could you Parallel the coils on each sub, and run them into their own channel on the amp? Run the amp at 2 Channel. Then each channel will run 2 ohm.

rthompson, is that correct?


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2000 Mercury Cougar Special Edition
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http://www.geocities.com/bustatail.geo/smith.html

 

The amp will run at the same temperature at 2 ohm stereo as it will at 4 ohm mono, if overheating is a problem at 4 ohm mono it will be the same at 2 ohm stereo. Like i said if the chambers are seperate, then running them in stereo will not cause the headaches that a non seperated box will cause (both subs hitting out of phase with respect to one another is a problem of a single chamber dual sub box.

gotbass, i am really suprised that the tuning frequency for an SPL only vehicle is that low, it sure seems like it is a shorter car than an F Body and the resonant frequency of F Bodys is around 51 Hz... a shorter car would be higher due to the shorter wavelength of the higher frequency... could you measure the car, it really doesn't look like the cabin is longer than a Camaro... oh well.

It also suprises me that you would hit that high with a 26 Hz signal since you should be unloading that sub to high hell, and i can't say that i have EVER seen an SPL only vehicle with less port area than SQ competitors, it just seems strange to me. Lots of SPL competitors are running close to the same port area as cone area... Honestly with an 8 cube box tuned that high i would expect a little more... i saw a guy do 151 with 3 12w3's in 1 cube boxes and a mere 500 watts (PG 2500), well that was a Talon.

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Actually EVERY setup i have heard for the L7 was sealed, and the sound quality was very lacking, and the smaller the worse it is going to get. The L7 12 is NOT... i repeat NOT a small box sub, it doesn't reach a butterworth alignment till it hits about 20 cubic feet. Most people just can't make a sealed box big enough to make them sound good. If you drive a van or a bread truck then you might be OK, but unless you can spare a whole lot of space, DON'T put them in a sealed box and expect them to sound good. If you are looking for good sounding sealed subs give the JL Audio W7, ID Max, and the Adire Brahma a try. The Brahma is bes tsuited for the smallest boxes, it achieves a Butterworth alignment in a .95 cube sealed box where the W7 and the Max are between 1.5 and 2 cubes.

I did notice that you said "I personally don't like the sound of ported"
Have you ever heard a sub that was optimized for sound quality in a ported box? Most ported boxes are built for people that like to boom, but if you heard a good ported setup you would certainly change your mind. Prefab ported boxes are notorious for being peaky and tend to lose low bass extension and the higher they are tuned the more you have to worry about unloading the subs (thus blowing them). If you are looking for a great sounding sub, i will say look elsewhere, the L7 just isn't most people's idea of "sound quality"

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Soundillusions.net
The ultimate in caraudio.

Sony, Arc Audio, Infinity, Adire Audio, A/D/S

 

You could be right. I might be able to get more out of mine. This box is exactly what Kicker designed for us. We gave them all the info of what I'd be running for amps, alt, power... I've been trying to break the 150 mark for a while now... and these are the only subs/setup I've been able to do it with. I've tried W6's W3's, Atomics, ID-Q's, XTR's.... a lot... always just 2 12's, and I couldn't get over 150db. Kickers did it for me. This is only the 2nd vented box we've tried. I don't know too much about ports, but this one is deep, and it sounds awesome.

Maybe I'll check with my installer about what he thinks with different boxes/ports. I know we went through Kicker, and then reconfirmed with M.A. on the specs for this box. We even had to ship in the wood from Kentucky (HDF).

I don't know, but you've got me thinking now..... I'd like to get more out of this box!!

Shon


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2000 Mercury Cougar Special Edition
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http://www.geocities.com/bustatail.geo/smith.html

 

I am using three lL&s chambered 1cu^3 each. I have not been to a meter but they get a lot of attention and are very strong I have a LOT of power to them (1200w each) and they handle well. You can break the 12s in faster by taking them out of the box and playing about 40-50watts into them for about 40 minutes @40hz.
I agree in a sealed box they are not much for sound quality as my midbass was zero until I added the R6's 6" midbass drivers. They are awsome expensive but awsome. If your box is less than 1.5cu^3 you should really use half polyfil (what a difference $6.00 of polyfil made)

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Black 00' SS
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(3) Earthquake 200Ds
(3) Marine Batteries
(1) 6 Farad Cap Bank
(2) 15" Compression Drivers (Loud AZZ Highs)
(1) Broken Trunk Latch courtesy of the L7s
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Well.... after some quick measurements and calculations here's what I came up with...

I can get ~ 2.1 cF per woofer... so.. starting out with 2.0cf in my formula's I get the following:

F3 = 35.58 Hz
Fb = 34.13 Hz
Pr = 5.74 db above ref.

Not too bad... I think I'm going to go the ported route.

Where should I set my Subsonic filter though?? just under F3 or??

Mike

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1997 Formula WS-6, 1 of 473

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