LaRazaUnida

Hi amigos,
I have a 1985 Mazda RX7 GSL-SE. I am going to put in 2 15 in. alpine subs in it. I want to know how to make a box for them. How should i get the most bump outta em. I heard i should port them. What does that mean? Would any one be willing to send me a diagram so i could make one. If any one could i would be extremely happy. my email is chicanopride25@hotmail.com THANKS ALOT!

John64

I would go to the Alpine site and sign in to the tech page. They have all the info on the sizing of the sub box. On 15's you normally will not port them. Big subs like sealled boxes. My friend had 1 15 in his rex and it shook the neighborhood. Just make sure you have tons of power or you will blow them. Subs don't fry on too much power they fry on distortion because of not enough power.

Aaron_M

i have a 12inch pioneer sub with box i will sell to you for real cheap.

specRX7_22

i have a 10" pioneer 350w sub with box i will sell you

MIKE-P-28

iTrader: (1)

Alpine 15? man they havent made one of those for a long time, I think when I stopped installing car stereo professionally, the biggest sub they had was a 12.

4 things about building boxes

1) MDF , use this, dont use freaking plywood
2) build the box as if you are gonna put water in it, seal it tight with liquid nails or silicone
3) build it the recommended size
4) if you have to ask about porting it, then dont port it

MIKE-P-28

iTrader: (1)

Im proud of ya! you are so correct, but this doesnt only apply to subs, it applies to anyhting with a voice coil

GENERALLY, power doesnt blow speakers, distortion does.

Gregs

there have been several threads on this

searching might get you the answers your looking for

-greg

Gregs

quick question, when i turn my deck up really loud, it skind of starts cutting out, i know its not my speakers, there brand new... could i have a weak power connection or ground?

-greg

FB II

yes

Gregs

so weak power, ground or both?

Anex 570

It is both, because the more signal there is, the more connection it requires or it will cut out, and yes not enough power due to your cutout/distortion. This WILL blow your speakers if you drive them that hard. I am a sound engineer for Bands/PA ect, and theres a few thing you need know reguardless of what you use if it be church, car, stadium, the same thing will happen in all. Id say that you should turn down bass eq a lil if its running hard on the low freq. or if you notice that theres quite a loud click to the music like a snare drum, the high is up too much. Back it down a tad and dont turn it up all the way all the time if it does what you described. If theres anything else you might wanna know just pm or reply. later

Gregs

Any suggestions on a stong power source i could tap a wire into for my deck?

-greg

Keaponlaffen

straight from the battery, with an in-line fuse 18" or less from the battery...

85rotarypower

I would suggest only using 1 15" sub. Even a cheapo sub will work. The car is small. You don't need a large speaker to make it sound loud. I have 2 10" subs in my Buick and they pound like hell. The best thing is, I bought them for $26 (canadian) each at Wal-Mart. Every time my friends are with me, they turn it down because the bass is so much. That is in a car with a larger interior area too. I expect them to be a lot louder in the 7.

BTW, They are rated at 175w max each. I power them with a 300w at 4ohms amp bridged to one channel. Considering I am running about 8 ohms resistance through the speakers, that would reduce the power to 150 watts max. I can still hit 120db without bottoming out the speakers. Power isn't everything. You can hit sound levels that you normally wouldn't listen at if your box is built right for the speakers.

joelwahid

i have one audiobahn 12 in my s10 in a ported box with 900 watts max going to it. it is loud enough to make my ***** rattle and my ears leak, i dont see why you would want two 15s in a fb.

Bayce

Yup. . .2x15's in a 7 is like...wow. I have 2x 12's
Custom made box - fits in back perfect, still leaves room for grocieries!
MDF ONLY! - Wood Glue and screws, all sealed with silicone - seperate the two speakers (Centre piece of MDF, makes like 2 seperate boxes even though it all one unit) NO PORTING.
Black carpet. . . rock on!

CheddaKing

Three Fifteens Literally shakes my entire cadillac, and that is a massive car, oh, and a 15 is a seriouslly huge speaker, are you sure they can fit and still get the right box volume. Oh, and if its a sealed box, you (should) get better power handling Correct me if im wrong guys. But yea, i dont think i could fit two fifteens in there, but good luck and let me know how it turns out!

Ritch

Someone who wants 15s isn't looking for interior sound. They want something to open the back of the car up and wow people two blocks away at the local hang out. It's for the chicks man.

Keaponlaffen

Exactly... Pretty much anything over 2x10" subs or one 12" sub is just for show...

"MY daddy could beat YOUR daddy up!"

Phiber Optik

iTrader: (2)

About 2 months ago I got 1st place at a db Drag stereo Compeition with 2 10" subs @ 147.6db in a box that took up the entire hatch area with the subs right behind your head and 2 4" aeroports firing at the hatch.

I made the box myself out of 3/4" MDF, pre-drilled the screws and woodglued all the corners and then inside the box I fiberglassed all the corners of the enclosure

If you want some space left in your hatch then I suggest that you point the subs directly at the glass hatch and place the box closest to the back of the car. Porting the box will give you more deep low extended bass, but with some subs you will lose some of the 'punch'.

For next years competition season I will have a wall with 2 12" Massive DMX subs check out the pics if you wanna see some serious subs
http://s87357361.onlinehome.us/index.html