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KTMrida4life
12-08-2011, 02:59 AM
Heres what I have decided so far. Im going to have someone on here help me with box design(s). Dunno who as Im new here. I am going ported. Not sure what kind of ported box, but I want to keep as much accuracy as possible. I listen to mainly rock/metal with the occasional rap here and there, but I want a box that does everything good all around. If thats possible.

I have decided on a Audiopipe AP15001 amp. 1500W rms @ 1 ohm. Cheap but the reviews for it look good. Better than the Kenwood I currently have..


Heres what I need help with. I have a tiny 2 door sports car. It is a 95 Nissan 240sx (S14). My trunk is small. I dont want to construct a box outside my trunk that will not fit, that would ****. lol

My amp is 1500W RMS. Ive looked for a single 12 (actually considered a 15) that can handle that, but I think Im leaning towards two 12s.


http://img4.imageshack.us/img4/5129/77764301.jpg
http://www.240sx.org/links/installs/chrisr/crobl2.jpg


Theres 2 pictures of my trunk that I found online. It is a funny shape with the spare tire at the bottom, which Im removing to save weight. There is a hump at the back which is for the gas tank which my amps are sitting on right now. I will take a pic of my trunk soon and get some dimensions, but for now, search s14 trunk online and you may find more.

Im open to suggestions on how to fit 2 ported boxes big enough for 2 12s in the trunk.

kushy_dreams
12-08-2011, 03:28 AM
You can easily fit 2 12s, 3 10s or a 15 in there. The opening is a pretty decent size too, so you won't have to build the box in there. Can your back seats fold down?

KTMrida4life
12-08-2011, 03:36 AM
Yes. But like I said, theres a very large hump that only gives you about a foot of clearance between the hump in question and the bottom of the rear deck. Im taking my rear speakers out so that should vent my trunk to the cabin of the car pretty well.

KTMrida4life
12-08-2011, 05:12 AM
I guess I'll still consider two 10s. Boxes would be a bit smaller and I would probably gain a little punch. Opinions? Im all over the place, cant make up my mind. lol

>>SQL<<
12-08-2011, 09:21 AM
I had that same car (my wife drove it) anyway it is a weird trunk, I do not see how you would get 2 - 12's ported without using glass.

I had 4 - 8's in a sealed box and had no room left in the trunk for anything.

KTMrida4life
12-08-2011, 05:05 PM
I had that same car (my wife drove it) anyway it is a weird trunk, I do not see how you would get 2 - 12's ported without using glass.

I had 4 - 8's in a sealed box and had no room left in the trunk for anything.

Yes it is a very strange trunk, thats for sure. Lots of space thats just not usable. Think one 12 in a ported box is doable?

>>SQL<<
12-08-2011, 06:15 PM
Yes it is a very strange trunk, thats for sure. Lots of space thats just not usable. Think one 12 in a ported box is doable?

yes 1 - 12 should fit fine. That would be around a 2.5 cube (b4 port and disp) box and that was around how big mine was.

KTMrida4life
12-09-2011, 12:30 AM
Heres a really crappy picture of some dimensions I took in my trunk. I forgot to measure how deep it is. If I had to guess, its probably around 22-23"?

http://img546.imageshack.us/img546/6134/trunk.jpg

Phoenix Risen
12-09-2011, 12:36 AM
do a nice single 12. the IA flatlyne or death row would be a killer option.

KTMrida4life
12-09-2011, 02:02 AM
Never heard of either of those.. I was looking at a Sundown Sa-12.

I may be able to fit two 10s.. Im cool with that too. :)

Phoenix Risen
12-09-2011, 08:52 AM
both the flatlyne and death row will walk on an sa-12. especially with the power you have, unlees you plan on running the amp at 2 ohm on the sa.

i personally would not recommend someone who is getting started with the 12v industry to be running ~1500rms to a 600rms sub, the sa can take it but it has to be done right. and the few builds ive done with the ap1500 its been on a pair of sa woofers. (one was in a cavalier doing a 143 on music with a pair of 12's)

granted the incriminatiors are a little more expensive. they are also much more sub.

The Flatlyne (http://www.soundsolutionsaudio.com/store/products/Flatlyne%252d12-D2-%E2%80%93-Incriminator-Audio-12%22-750W-Dual-2%252dOhm-Flatlyne-Series.html)

The Death Row (http://www.soundsolutionsaudio.com/store/products/Death-Row%252d12-D2-%E2%80%93-Incriminator-Audio-12%22-1000W-Dual-2%252dOhm-Death-Row-Series.html)

both are very well built subs. the flatlyne is a bit more sq oriented than the DR but both will perform very well.

KTMrida4life
12-09-2011, 01:01 PM
both the flatlyne and death row will walk on an sa-12. especially with the power you have, unlees you plan on running the amp at 2 ohm on the sa.

i personally would not recommend someone who is getting started with the 12v industry to be running ~1500rms to a 600rms sub, the sa can take it but it has to be done right. and the few builds ive done with the ap1500 its been on a pair of sa woofers. (one was in a cavalier doing a 143 on music with a pair of 12's)

granted the incriminatiors are a little more expensive. they are also much more sub.

The Flatlyne (http://www.soundsolutionsaudio.com/store/products/Flatlyne%252d12-D2-%E2%80%93-Incriminator-Audio-12%22-750W-Dual-2%252dOhm-Flatlyne-Series.html)

The Death Row (http://www.soundsolutionsaudio.com/store/products/Death-Row%252d12-D2-%E2%80%93-Incriminator-Audio-12%22-1000W-Dual-2%252dOhm-Death-Row-Series.html)

both are very well built subs. the flatlyne is a bit more sq oriented than the DR but both will perform very well.

I thought the SA 12 was closer to 1000w RMS sub? Thats what I saw on another forum anyway.

Those are expensive.. I cant do that new. Im sure you get what you pay for but its just way over budget. If I can find one used Ill consider it depending on price, but new thats a no go. I got about 150$ for a sub and I plan to hook it up at 1 ohm (full 1500W) so I want whatever is going to work the best for that price. Thanks for the suggestions, keep em coming

IonRL205
12-09-2011, 01:09 PM
They are rated at 600 rms, but people put 1000 to them no problems. Running 1500 is a different story though, I would look into a different 12 if you plan on running a full 1500 watts to it.

KTMrida4life
12-10-2011, 01:22 AM
I found a FI Q 15 on here, going to run it ported. Think I can make it fit? :]

Phoenix Risen
12-10-2011, 01:35 AM
its going to be very tight, and may be next to impossible with out doing some glass work

just a side note, im going back to a 12 after running a few different 15s in way too many boxes. i just couldnt get the low tuning that i really wanted out of the 15 and still keep enough port area to not have any noise.

just something to think about.

KTMrida4life
12-10-2011, 02:26 AM
Noise as in port noise?

That shouldnt be an issue.. its in my trunk. If it makes enough port noise for me to hear it from the drivers seat thats a problem..

What do you mean by glass work? Fiberglass? How would that help?

IonRL205
12-10-2011, 02:33 AM
Your best bet is to just go with a 12. You'll be better off with a properly ported 12 than you would with a cramped 15. To give you a little idea, my box for my 15 is 3ft³ (pretty much the minimum you would want for a 15) @ 31 hz and the dimensions are 34" wide, 17" tall, 17" depth (from front of box to back)

KTMrida4life
12-10-2011, 02:47 AM
Your best bet is to just go with a 12. You'll be better off with a properly ported 12 than you would with a cramped 15. To give you a little idea, my box for my 15 is 3ft³ (pretty much the minimum you would want for a 15) @ 31 hz and the dimensions are 34" wide, 17" tall, 17" depth (from front of box to back)

That will almost fit man. I can make the box at least 35 inches across (maybe taper out to 40ish) and 16" deep by 12" tall. Thats over 3 cu ft... I think I can make this work. I really need to get in touch with a good box designer and give him some dimensions and see what he can do.

BTW, the amp Im getting is 1500W. I dont know of one 12 in a decent price range that can handle that.. probably a bit too much power for a 12 anyway, and I cant afford 2 12s. Why I thought about the 15.

kev28
12-10-2011, 02:57 AM
my fr man he friend has a nissan 249sx he walled his you should consider it look on youtube under team ridiculous soundz seans first day back you will see

KTMrida4life
12-10-2011, 03:12 AM
my fr man he friend has a nissan 249sx he walled his you should consider it look on youtube under team ridiculous soundz seans first day back you will see

Took some searching but I finally found it.. Im good man. LOL. Thats the older 240sx, the S13. Only a year between mine and it but it is a totally different car. I think its actually a hatchback.

Anyone know any good box designers? Im going to make another thread.

KTMrida4life
12-10-2011, 04:00 AM
Looking for something like this.

http://img444.imageshack.us/img444/4097/boxpe.jpg

BTW, google sketchup is amazing. Very fun and pretty easy to use.. wish I knew more keyboard shortcuts and how to do other things than draw rectangles and push/pull.

Thats a very basic idea of what Im thinking I can do. Box is 35" at the rear, extends out 10", then opens up to 40". Box is 12 5/8" tall. Accident on my part.. forgot to figure in thickness of MDF. No idea how much airspace.. would this even work acoustically? Does it matter what shape a box is?

Phoenix Risen
12-10-2011, 04:45 AM
BTW, the amp Im getting is 1500W. I dont know of one 12 in a decent price range that can handle that.. probably a bit too much power for a 12 anyway, and I cant afford 2 12s. Why I thought about the 15.

there are a lot of 12s out that will take 1500, im going to be putting ~4500 to mine once its built....

as because the dimensions you can get are 3 cubes that does not mean that you have the space for the port, bracing, and the sub. and can still end up with 3 cubes.

and btw, pretty much any 15 on the market that will take 1500 the 12'' version will do the same.

and in ported enclosures shape does matter a bit, but at your level youll not really notice it.

KTMrida4life
12-10-2011, 05:37 AM
and in ported enclosures shape does matter a bit, but at your level youll not really notice it.

Not sure why I was doing the angles, just gonna make for a PITA later. Heres a revised version

http://img32.imageshack.us/img32/6294/boxrevised.jpg

Inside dimensions for the rear section are 10" x 33.75" x 11.375" (height) and for the front section 40.75" x 6.5" x 11.375". I did the math and got 3.95 cu ft. Sub displaces .24. Leaves me with about 3.7 cu ft before bracing and port. Is that enough? How much displacement does a port usually take up? I may be able to make the box bigger.. I know I *can*, Im just scared I wont be able to get it into the trunk. My head would probably explode in anger... lol

Also, this is about as far as I can get right now. Im confused at this point, need to talk to someone who knows their stuff or do a ton more reading. Im confused about where to put bracing and the "tunnel" (right word?) that I keep seeing in your typical box diagram... like this.

http://img30.imageshack.us/img30/1520/35cubes32hz5425sqin5gq.png

Do I need to still do that if I use a PVC port or is that little right angle tunnel only if your using a slot port? Noob questions here someone help me out...

I made enough room to mount the sub on top of the box firing upward and I want the port (PVC pipe I guess) over to the side, hopefully firing up through one of my rear speaker openings and subsequently my rear deck. Thats the plan anyway... Im going to measure my trunk again tomorrow a little better, I did it in the dark last time with a flashlight.

Also, where do I need bracing inside the box?

Phoenix Risen
12-10-2011, 12:45 PM
ok, you dont want to have right angles in your enclosure if you can help it at all. the inside surfaces should be as flowing as possible.

the reason there is a bend in the port is because it has to be a specific length to get the required tuning. and often times that length is longer than any one wall in the enclosure, and yes the same rule can and will apply to areo and pvc ports (thats the big reason i dont use them..

the last enclosure i built for my xxx 15 was 3.5 cubes net and tuned at 36. it was just over 5 cubes gross before all displacement, so ports especially larger ones will take up a lot of space. which means that your 3.9 cubes most likely is going to be too small for a 15 once things are all said and done.

i still say the best be is to go with a strong single 12 and call it a day. or even a monster 10...

running a smaller sub in the proper sized and tuned enclosure will get greater results than running a larger sub in a cramped poorly designed one.

KTMrida4life
12-10-2011, 05:54 PM
ok, you dont want to have right angles in your enclosure if you can help it at all. the inside surfaces should be as flowing as possible.

the reason there is a bend in the port is because it has to be a specific length to get the required tuning. and often times that length is longer than any one wall in the enclosure, and yes the same rule can and will apply to areo and pvc ports (thats the big reason i dont use them..

the last enclosure i built for my xxx 15 was 3.5 cubes net and tuned at 36. it was just over 5 cubes gross before all displacement, so ports especially larger ones will take up a lot of space. which means that your 3.9 cubes most likely is going to be too small for a 15 once things are all said and done.

i still say the best be is to go with a strong single 12 and call it a day. or even a monster 10...

running a smaller sub in the proper sized and tuned enclosure will get greater results than running a larger sub in a cramped poorly designed one.

I still think I (or more likely a box designer) can make this work.

Good to know about the right angles, I thought about that. I will have to figure something out there.. is there any size requirements for a port (PVC, length, width) or is just whatever it takes to achieve the correct tuning?

Im going to measure my trunk again.

disturbed471985
12-10-2011, 06:01 PM
Member guys he has a budget of under 200 bucks.. There are not many 12's of quality out there for that price that can take a solid 1500 daily... PM pro-rabbit or Ram_Designs or DonH for a box design..

Here is one that will - http://www.ebay.com/itm/American-Bass-XFL-1222-2000W-12-XFL-Sub-Car-Subwoofers-Dual-2-Ohm-2000-Watt-/260855236550?pt=Car_Subwoofers_Enclosures&hash=item3cbc2f07c6

audiobaun
12-10-2011, 06:41 PM
I have a 90 model 240sx, and I ran a pair of Audiobahn AW1006t 900rms 10s in there in a single enclosure with two chambers ported with 1.6cuft perchamber, and them off of The Audiobahn 18001dt mono amp with an oldschool USA US Acoustics Series II 4080 on a pair of Kicker 6.5, and ks25 tweeters, and a pair of 5.25 in the rear pillars, and sounded GREAT! I built a false 3/4in floor to level out the surface across the rear floor.Get rid of the Cheap Fiber board cover.I also recommend putting deadner on the bottom of the tire well and the rest of the area, as the road noise is pretty loud.I ran 4ga power supply, and had no issues with a small kinetik battery.Though, no real room left for anything, and nothing exposed visable from outside the vehicle .All in Hatch space.I recommend tens, for the air space you have.Sounded Great for me!:cool:

KTMrida4life
12-10-2011, 10:04 PM
Thats what I have =\ Granted their not great 10s but theres still 500W going to them.


If I cant do 90 degree angles... what can I do instead? Could the outside of the box be a 90 degree angle, but on the inside I screw/staple/attach some very thin plywood bent around the corner to smooth it out?

I know I could do just a bit rectangle, and I still can. Just trying to avoid leaving about 10 inches on either side of the box..

disturbed471985
12-10-2011, 10:09 PM
Yes u can just use 45's in all the corners problem solved.

audiobaun
12-10-2011, 10:16 PM
What tens do you have again? I still have my box that I made myself, and can measure it.I just made it out of 3/4MDF,Rectangular, and sealed it in and out, and made my own ports out of PVC 2 1/2in x 7 3/4 deep, and sealed the outside with flexstone paint.I fired mine straight up at the glass.Pushed the sub box all the way to the left side for all the amps, and power wiring on the right.Whos to say it needs to be directly in the middle?Didnt seem to make much of a difference in sound either way moving it around ..to me though.You can also tilt the box at that angle, and put support L brackets/bracing under it?

KTMrida4life
12-10-2011, 10:31 PM
Yes u can just use 45's in all the corners problem solved.

Great. Now if I can just figure out how to do that in google sketchup. haha

Fi_
12-10-2011, 10:39 PM
A flatlyne WILL NOT kill a SA-12... If anything they are about equal if not the SA-12 is better and for the $320 a subwoofer YEAH right... I like IA but personally don't think their prices reflect their products well at all.

KTMrida4life
12-10-2011, 11:01 PM
F this Im building a freaking rectangle. Trying to make it taper out just isnt going to work.

Edit- Slight problem. I cant fit any box in my trunk that is deeper than 13 inches. I just tried with a piece of cardboard. Would tapering the backside of the box so its kinda hatchback style fix this or does that still not help me? I cant figure out how to get enough airspace for the sub.. it stinks cause the trunk is plenty big enough but it just wont fit through the opening.

Unless I just go sealed. How would this sub sound sealed? Still plenty of boom?