RE XXXv3

Unloading is when the sub tries to move more than it should to produce sound, which can happen when it's played below tuning. With my box tuned @ 36hz, when I was going through songs once, I stopped on a 20hz test tone and it was the loudest to the ear I've ever heard it, it was over-excurting like crazy and while it sounded awesome it looked so bad for the sub, it looked like it was going to pop out of the box. Maybe a week later it blew a tinsel playing lows on music.

I want a BTL comparison (efficiency) and I want to see what a 15 or 18 can do in a car trunk on RMS in a really nice box. I know a small company needs big profit to stay alive (is SMD backed by AA?), but why are these subs over $1000, does it cost $700 for materials or is it $400 and a huge profit is made because of the name behind it? You can bet if it were a little more expensive than a BTL ($500-$600) it would take Fi's sales but that's not going to happen at $1000+. For most people using a higher-powered setup, price is the largest factor when buying a heavy duty sub and most skip to the BTL because she's reputable & cheap. If the SMD is like two BTL's in one than charge a little less than double the price for a BTL (BTL $400, SMD $700). Will they ever get cheaper?

8 sealed Dcon 12's in the same box powered by a Hifonics BXI2408D @ 1ohm with a HD batt and around a 270A alt (all I could find). I'm wire-savvy. I don't want to use two amps because they don't use clicky notches on the gains and filters. Box is going behind my Alero's front seats and if it'll fit height wise I'll toy with a crappy wall.

Thanks. The12volt goes up to 4 subs where 4 S4 = 1 ohm and 4 D4 = 2 ohm. Does 8 S4's = 2 ohm? I thought wiring options were either series or parallel, not both, confusing!

Between S4 & D4 which is needed to wire 8 subs to 1 ohm?

1. How old are you? 22 2. When did you get into car audio? Friend took me to a show when I was 17, didn't know what bass was! Loved it though. Sat in a beetle with 6-15's. 3. How did you first get into car audio? First car, bought a sealed 10", it was crap. 4. Whats your favorite color? Gamma-ray blue 5. Male or female? Male 6. Your first Car? Buick Lesaber, don't buy one. 8. How did you find out about this site? From SSA of course. 9. What was your first system? Oh god, a sealed Sony Xplod 10 powered by a Schosche 220w. Was a lot better with 2 sealed Pioneer 175W RMS 12's. 11. Were do you live? Ontario, Canada 12. Whats you favorite car audio brand? Fi for the BTL & SSA for the Dcon. 15. Who is our hero in the car audio industry? The person that designed the BTL and the DCON. NOT Eclipse for taking out the SW series. 16. Whats your dream system? In a hatchback, something like 4 XCON 18's sealed in a wall at the back on 7k. 17. Whats your dream car? Mostly the SVT Focus because of space. 18. Whats the fastest car you have driven/ridden in? Firebird? Not sure, went 100mph. It was kinda slow. 19. Were do you buy most of your car audio products? Online or EHR. 20. What is your job? What's that? 21. Whats your favorite saying? Eternal suffering awaits all those who question god's infinite love. 24. Whats your favorite brand of cars? Mitsubishi for the new EVO. 25. What do you like better, cars, vans, trucks, or suv's? Ext. cab trucks, gotta have subs & a dirtbike. 29. Whats is the most recent thing you have purchased? Smokes. 31. Who do you think is the most knowledgeable person on SSA? Thumper. 32. What is your personal best on the TL? and with what equipment? My guess is 140db with a 2005 RE XXX 12D2 in a 2.2 cf3 slot port powered by a Visonik V900XD in a Sunfire GT trunk. 33. SQ or SPL? why? If it can't play music it's pointless, 30-35hz tune only. I prefer the flat response of a sealed box but not if it's below 145-150db. I had an 05 XXX, Eclipse SW8200, and an Atomic APX, all 12's in the same box. The XXX sounded best, Eclipse got low, the Atomic just sucks no matter what it's tuned to because you can really hear the crappy sound of the cone. I wired the Eclipse to get 750W and there was maybe a 1dB loss, so double the power doesn't mean much to me. As long as it's efficient, can hit the musical lows, and doesn't sound like an APX, it's good.

I'm almost sure that x-max only matters when it goes below port tuning or if it's in a sealed box. If it's above port tune you aren't using all that excursion and something with less excursion should sound tighter, especially if there's more motor force.

What tune is 2.75 and 3 cubes? .2 displacement?

I paid $300 for a 2.2 cube @ 37hz slot port box and I NEVER WILL AGAIN! IT TOOK MORE THAN WEEK FOR THESE 2 DUDES TO BUILD ME A TINY BOX AND THEY HAVE NO OTHER BUSINESS. Spend $50 and trust yourself using tools. Plan it all out and you'll have it done in 3 hours.

If your back seat folds down than point it all forewards and shape a piece of something (leather on particle board) to somewhat seal it. If the sub has to be upfire, than point the port to the rear of the car. Upfire isn't good because it'll rattle the crap out of all that metal on the trunk lid and rear deck. If you can fit 21.18" x 39.37" than you can point it forewards into the car. I assume your port is 19.18 x 5.2 which = 99.736 square inches, which isn't 16 per & 132 sqin, it's 12. You can't go for 7.5 cubes, 16 square inches, 120 square inches? For a slot port that'll be tuned around 31-33. It might belt out the lows just as well with 8.25 cubes having more port area per cube.

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

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".

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?

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.

The difference between a 12" and two 10's is 113 vs. 157 = 44 square inches, where 50.25 square inches is an 8" speaker, it's nearly unnoticable. I'd rather buy a 12" BTL on 2300-2500W rather than 2 10's with 1000W each. The BTL has better efficiency, it should do more with it's power and might equal out, so go the cheaper route. Eventually you'll just want another 12" BTL and after dropping on a 12" and another 2000W you'll be wondering if the 5dB was worth $1000. A 15" has 176 square inches, it would be cheaper/louder to get a 15" BTL and stick it in 3.5 cubes (the 10's would probably be 3 cubes so half a cube isn't much).

How do you not know your sub is on?

A high output alternator, mayyyybe another battery, and the big 3.

I kind of thought they were all the same - you get what you pay for, so, the most expensive one? I had a 7" flip-out touch-screen ($1000) that was stolen along with my sunfire. It was ghetto fab haha.

Does it matter how much space the woofer has from the sides of the box? I like to use 1" MDF and 1" spacing but this 18" idea will require .75" mdf and no spacing. 18.5+1.5 mdf = max. 20" height, good idea, just, that's soooo much work to the reardeck. If you cut up a rear deck will the car be all flimsy?

What about 1500W @ 2ohms? How many alt & batts would I need for that and a 600ish watt component amp? I've always wanted to use my Eclipse SW8200's sealed, but I doubt it'll be as loud. I've tried them sharing 750w and it wasn't as loud as my XXX but went a lot deeper. I might just try that.

An 18 on 2k and 2 12's on 4k is about the same thing, right?

The max height is 17, 15.5+.75" mdf = 17 - no spacing, I don't want that and I'd like to use 1" mdf, if I was using a 15" I'd use 19.5" height, if I used this triangle calculator correctly, if the height is 17, than to get 19.5" (height), I have to add 9.56" to the bottom, so I halved it like this: http://www.reaudio.com/speaker_box/LPort_Box_Calc.html 37 width 17 height 15 24.56 (+9.56 1 4.27 (64.05 square inches of port) 4.582 - .21 displacement = 4.372 @ 36hz. Add .5 to each depth and it's 4.715 - .21 = 4.505 cubes @ 35.5 hz. I don't know if -4.78 & +4.78 is enough space for magnet clearance, probably not with 1" spacing. The only way I could do an 18" foreward fire is if I cut up the stuff that connects the rear deck, which is something I'd do. 37 x 20 x 30 / .75" mdf, 7" port, 129.5 square inches, 8.312 - .26 displacement = 8.052 @ 31hz. That's with .75" mdf though, and there would be no spacing for top & bottom, is that a problem? That box would slide right in if I could fit 20" tall, which is the top of the trunk. It's not a bad idea. I'd rather have 2 12's over the 15, just for cone area.

I'd rather have 2 btl's on 2k than 2 q's on 2k, just so when it's cranked I know the subs aren't at max. output, but is the output exponentially worse at half power? In my old/stolen sunfire 2-door I had a 90amp alt, a visonik V900XD 1500W @ 1ohm, 2 runs of 1/0 and an 05 RE XXX 12D2 in 2.2 cubes @ 35 or 37hz that was facing the trunk lid, without the big 3, and I was very happy with it, my rearview fell off twice. Now I have an 01 Alero 4-door and I want 2 12's with everything facing forewards, blocking off the trunk using the max. dimensions (17 x 37), it will be louder I'm sure. Is 2 btl's or 2 q's nearly the same on 2k or will it not move the BTL enough and give the edge to the Q? I had an APX on 1500W and it hardly moved but was about the same dB. Box is 2.7 @ 33hz, depth is 26 so I don't have any space for batteries in the trunk, unless I did 2.4 cubes each @ 35hz, the depth would be 23" leaving 7" for battery width. Still, 2 btl's and the box is already 250lbs, I can't afford the gas on that. DD9512's would be cool but I've never heard them.

I'd rather have 2 btl's on 2k than 2 q's on 2k, just so when it's cranked I know the subs aren't at max. output, but is the output exponentially worse at half power? In my old/stolen sunfire 2-door I had a 90amp alt, a visonik V900XD 1500W @ 1ohm, 2 runs of 1/0 and an 05 RE XXX 12D2 in 2.2 cubes @ 35 or 37hz that was facing the trunk lid, without the big 3, and I was very happy with it, my rearview fell off twice. Now I have an 01 Alero 4-door and I want 2 12's with everything facing forewards, blocking off the trunk using the max. dimensions (17 x 37), it will be louder I'm sure. Is 2 btl's or 2 q's nearly the same on 2k or will it not move the BTL enough and give the edge to the Q? I had an APX on 1500W and it hardly moved but was about the same dB. Box is 2.7 @ 33hz, depth is 26 so I don't have any space for batteries in the trunk, unless I did 2.4 cubes each @ 35hz, the depth would be 23" leaving 7" for battery width. Still, 2 btl's and the box is already 250lbs, I can't afford the gas on that. DD9512's would be cool but I've never heard them.

The difference between 2k and 4k should be around 3db right? If 1 battery can sustain 2k that's fine, but would 2 subs that are 1000 RMS be louder? I wouldn't mind using 2k if the subs will last longer, 2 12's and 2k is more than what I had, as long as I'm louder than a 12/1500w. What about using an amp at .5 or .25ohm, does that still need the battery power or is it the amp that's pushed harder?