How's this box look?

[RE XXXv3 31]

For my Alero trunk I'm eventually going to buy a BTL 18 D2 with daily/all options. This is the cheapest & loudest daily setup I can think of and I've drawn up a shizload of boxes. I want lots of bass but don't want to shell out for a huge amp, alt, and batts. Power will be maximum 2000-2200 watts @ 1ohm unless I can borrow a huge amp for burps if having 1 fully charged battery will git-r-done. I will buy 1 battery and upgrade the alt if I have to but nothing crazy.

RE Enclosure Calculator

1" MDF with 1" double baffle and no other bracing besides rabbit joints which I still am not sure if to use .25".

37 width x 28.72 depth (29.72 with baffle) x 20.5 height

Displacement: .26

Port L x W: 18.5 x 6.5

Port area: 120.25

Box volume total: 7.776

-.26 = 7.516 @ 31.86 hz.

120.25 / 7.516 = 15.999 sq. in. of port per cube.

Should I position the sub evenly or leave it to the opposite side of the port?

If I burp at 32hz how much power do you think it'd take and is that the safest burp freq?

Should I run the wires tightly through the port?

Should I use a foam seal?

I've seen on youtube people are throwing 3500w at them, and meade 7500w? How long will that last? Can you safely go over 2000W without hearing drastic changes in sound quality?

How do these perform below port tuning and do they sound drastically different at that point?

Thanks.

[emh9009 199]

I’m no pro, but I’ve read around here that the RE calc. isn't very reliable... and there isn't really any need to go over 2k watts. The most I would do would be 2.5, but that’s me. I would rather keep the sub alive than tear it to pieces. You won’t notice much (if any) of an audible gain in dbeezzz

I highly suggest at LEAST a huge batt. up front with big 3 in 1/0 wires. Depending on your stock alt. if you need a bigger one or another battery. Get a volt meter to watch your voltage while playing it, should be good.

Anyone please correct me if I'm wrong on the electrical

This isn't a "SQ" sub so you really shouldn't be using that term anywhere in your post.

as for burping freq. you need to test your own car and see where it peaks at, that will give you the loudest tone for your car, why did you jump right to 32 hertz?

That’s a pretty beefy sub, i would def. look into bracing. Something is better than nothing

Oh, and remember post a build log with lots of pictures!

[RE XXXv3 31]

If I use an amp that does 2000w @ .5 ohms will that lessen resistance and batteries needed? Is there an audible difference in the already-non existant SQ between .5 and 1 ohm? I forgot that even if I burp at 32hz it'll have cabin gain but I thought the closer the frequency to the box tune the cone will move less and be able to take more power for a burp. It's a daily setup so nvm burps at 2000w. I'd rather get 35hz but it's okay because I listen to bottom heavy rap. My 05 XXX 12 was 2.2 @ 37 and it didn't hit the lows like I wanted. I was thinking the resonant freq was around 40hz. What's a good amp that'll power it safely either at .5 or 1ohm/2000w? To fit this in the trunk I have to cut and brace a part of the rear deck. I have 10 x 20.5 for amp space on the box like |port|amp|sub|. I'm hoping it changes the air pressure in the car etc. What's a better slot port calculator? 2" MDF and rabbit joints aren't enough structure?

Edited January 21, 2010 by RE XXXv3

[thebiggmann12 14]

i would look at an saz2000d or a audioque 2200d. ive heard they are both very good amps, the sundown is expensive but it is definately worth the cost. but if ur on a small budget the audioque would be the way to go. dont run an amp at .5 ohm...there is no sense in it for a daily setup...just get an amp that is rated at 2000 watts at 1 ohm.

[BKOLFO4 29]

1" MDF with 1" double baffle and no other bracing besides rabbit joints which I still am not sure if to use .25".

37 width x 28.72 depth (29.72 with baffle) x 20.5 height

Displacement: .26

Port L x W: 18.5 x 6.5

Port area: 120.25

Box volume total: 7.776

-.26 = 7.516 @ 31.86 hz.

Box looks pretty good. RE calc seems to always be a little off. I come up with ~28-29 inch long port. You can run the port wall into the box so it is 6.5" from the back wall, and you will be good. End up with 7.6 cuft tuned to ~32 Hz.

Should I position the sub evenly or leave it to the opposite side of the port?

Even is fine. Looks better.

If I burp at 32hz how much power do you think it'd take and is that the safest burp freq?

You burp based on the peak factoring in the vehicle cabin too. It will not be the port tuning frequency. If you are just worried about a burp score, you have a lot of testing to do. If you will play music, tune to 32-35 Hz, then test and find the peak for your burp.

Should I run the wires tightly through the port?

Why run them through the port? Drill a hole in the box, run the wires through, and seal the hole.

Should I use a foam seal?

For what?

I've seen on youtube people are throwing 3500w at them, and meade 7500w? How long will that last? Can you safely go over 2000W without hearing drastic changes in sound quality?

2k is more than enough for daily. They can definitely handle more if you have the electrical system to back it up. . .

How do these perform below port tuning and do they sound drastically different at that point?

They don't. No sub does. If you want lower, tune lower or you will be back here with a topic "My BTL stopped working"

[BKOLFO4 29]

If I use an amp that does 2000w @ .5 ohms will that lessen resistance and batteries needed? Is there an audible difference in the already-non existant SQ between .5 and 1 ohm? I forgot that even if I burp at 32hz it'll have cabin gain but I thought the closer the frequency to the box tune the cone will move less and be able to take more power for a burp. It's a daily setup so nvm burps at 2000w. I'd rather get 35hz but it's okay because I listen to bottom heavy rap. My 05 XXX 12 was 2.2 @ 37 and it didn't hit the lows like I wanted. I was thinking the resonant freq was around 40hz. What's a good amp that'll power it safely either at .5 or 1ohm/2000w? To fit this in the trunk I have to cut and brace a part of the rear deck. I have 10 x 20.5 for amp space on the box like |port|amp|sub|. I'm hoping it changes the air pressure in the car etc. What's a better slot port calculator? 2" MDF and rabbit joints aren't enough structure?

.5 ohms will more than likely require more input power to the amp, as most amp's efficiencies drop as the output impedance is decreased. This means you need MORE batteries/alt to run at .5 ohms.

The cone will move less at tuning, but there is normally more output just above tuning. . .With 2000 watts and a 32 Hz tune, you can burp at any frequency above tuning and you will be just fine.

I agree with the AQ2200 or Sundown 2000D. Ethier one will be great and you can run at 1 ohm.

[RE XXXv3 31]

I made a nicer setup for 2 btl 12's that can play with the seats up and its firing foreward, 6 cubes @ 32.25hz with 16 sqin of port per cube says the RE calculator, the spacing is all symmetrical and the max height is as much as I can go before having to take off the rear seat latch so this is better, the port is firing into the smaller part of the fold down seat so I can have the seat down and port firing into the car with 2 people in the back. I don't know where to put the batteries for 4k, maybe stuff them in the corners. 38.15" x 17" x 27.79"/1" mdf/6.4" x 0".

[RE XXXv3 31]

37 x 16.5 x 26.91/1" mdf/ 6" x 14.5" port. 2.7195 each @ 32.77 hz.