Four 15’s?

I went to a local install shop for an opinion, and they said four 15's requiring about 2 cuft for each chamber cannot fit into a 99 cavalier. The customer doesnt want a wall or anything like that, but rather just a box to fit four 15's, has anyone tried this?

Its totally doable if you build the box inside the car. I did 4 12's in a box that was chambered and each sub got its own 2 cubic foot chamber and ported. I know for a fact that if I had built it a little different 15's deffinatly would have been possible.

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

how did u build the box? as in like how were they facing?

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It is better to remain queit and have others think u are dumb, then to open your mouth and remove all doubt.

How about Iso-Loading the woofers?

Iso loading will require twice the amp power, BUT it will cut the box size in half. You'll could do 2 cuft per pair (clamshell-mounted) and thus you'll only need a total of 4 cuft enclosure space for all four woofers.

I did this myself just a few days ago with four 12s - 1.7 cuft per pair, and it's working out great.

///Leif

Just to clarify, if you wanna google this, search for "isobaric".

///Leif

I had 4 fifteens in my cavalier, and my civic. I don't think that you will be able to get 2ft cu per sub. What I had was around 1.75 per sub and had the subs inverted, I also had adequate power. The box was around 30x36x12. As far as iso loading them, it is not worth it IMO.

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I would not go "iso". It will give you room for 4 15's, but the sound will be like only 2. look on "woofer enclosures" on this site and it will tell you every thing you need to know about "isobaric". I think you could build a 4 15 box for that car. just do your home work. What kind of subs are they, do they need 2 cf each. they might need just a little less. or the may need more so you might have to look at some other subs. The customer will need to know that with that kind of install he will lose his trunk. good luck.

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Big Dave

You're absolutely correct that that 4 isobaric-loaded woofers is a 4 cu ft enclosure will sound like 2 of the same woofers in an 8 cu ft enclosure.

However, you may be forgetting that 4 of these woofers mounted normally in a 4 cu ft enclosure will sound like LESS than two woofers at the same frequency. As you add woofers to the same airspace, low frequency efficiency goes WAY down.

It all depends on what your goal is, miniloompa.

Do you want SPL (i.e. as loud as possible, who cares how it sounds?).. In that case, mount them in whichever sealed enclosure will fit (make sure they have separate compartments) and it'll certainly be loud :).

If SQ is of importance though, I still stand by my recommendation of iso loading. Low frequency extension will be absolutely incredible with those drivers. It won't be as loud as a conventional enclosure can be at high frequencies (over 60hz or so), but it will probably be much louder at low frequencies (under 40).

///Leif

By build inside the car I meant that the box has to be assembled inside the vehicle because he finished box will not be abled to be manuvered into the vehicle because of its size. It wont fit threw the openings provided. You can however take out the back seat and build the box in three pieces one piece holds two subs then the second piece would drop inthe back and the thrid piece would slide in after you take out the back seat. Takes lots of planning but can be done. And I guarentee that you can get 2 cubic feet per sub.

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

when you say a "cavalier" what do ya mean? cos we got cavs over here but not '99 ones... who make them?

GM makes cavaliers and sell them by the thousands. Probally one of the most popular cars sold due to low cost and a huge die hard GM fan base

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

hey thanks for all the replys. yes its the chevy cavalier 1999 2 door 2.2L. The two subs i was looking at are either the Diamond Audio CM315D4, or try to find a JL 15" w3v2. I know that the JL woofer needs 1.50-2.75 cu.ft for a sealed enclousure. I have not been able to find much on the Diamond. If anyone has any other suggestions for a lower powered woofer that i can afford to buy four of. And YES, SPL IS THE KEY. The goal of this car is to shake other around him. He wants the loudest possible. He has limited power to work with. He has 2 amps, running 800 watts @ 4 ohms bridged. The JL's and the Diamonds will both be under powered by qutie a bit, but he is willing to take that risk i guess. So does anyone have any hints or suggestions or diagrams for building such a box? I think that i wont let the guys at the shop install it, they want over 500 bucks just to build a box for four 12"s which i could do myself. Is this new box going to be as hard as i hope it isnt? lol...thanks again everyone for the input and any other sub recommendations would be appreciated.

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It is better to remain queit and have others think u are dumb, then to open your mouth and remove all doubt.

He also is looking at the Cerwin Vega VEGA-154 in addition to the DA and the JL...sorry forgot to add that one, he also likes the type R, but i thought that was more of a SQ sub than a SPL sub

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It is better to remain queit and have others think u are dumb, then to open your mouth and remove all doubt.

here's my 2 cents"  There aint no dam way that lil alternator could keep the amps running first off, , so spl aint gona happen, , , stick with 2 15's, in big box's and feed them 800 watts each, , they will pound for 2 seconds, , then he'll have to drive for a half hour before he can unleash another 2 seconds of fury .

Besides, , its a gm, , onces it gets loud the trunk will break off, the wheels will come loose, and the roof will fall off, , then mr.goodwrench will fondle it back into shape useing genuine recycled shopping cart parts.

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2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.

Ok heres the deal. He has been running those two 800 watt amps with his 2 12's for about 6 months and the lights dim a lil bit when the bass hits, but the alternator is holding up. He is kind of set on the four 15's. What brands/models would u recommend for the 4 15's, and if i can talk him into having just 2 15's, what brands/model would u suggest for that....iknow ported is more for spl, but wouldnt u agree that sealed would be fine for this application?

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It is better to remain queit and have others think u are dumb, then to open your mouth and remove all doubt.

How about Resonant Engineering XXX15s or even the cheaper ones. www.bladeice.com i think is the site. These are VERY good subs but you do have to pay for the quality.

Actually, since you are dealing with low power and want the most SPL possible, I would be doing ported as this is going to give you more boom out of the power you have, provided the box is ported properly.

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double-secret reverse-osmosis speaker-cone-induced high-level interference distortion, Its a killer

i agree there, however, with limited space and him trying to cram as much gear into his trunk, i was leaning to sealed because the ported will take much more air space, thats the only thing..any more suggestions for brands or comments on the ones suggested?

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It is better to remain queit and have others think u are dumb, then to open your mouth and remove all doubt.