AmericanLegend

Cool^^ you sound like me You can use a roundover bit on a double port baffle.

I am working on a blow-through enclosure for a 2000 Saturn with 2 Big Bang 15DVC's right now. I'm going with a 4th order bandpass (sealed/vented) that will be 10.5 cubic feet (internal) tuned to 70 hz. The box promises to be a low bass monster off of only 1500 watts RMS or so. It is pretty easy as long as you know what your goal is before you start. If you're still lost at the end of the day, I will post some build pics to maybe help get you thinking about your own car. For what it's worth, this box was commissioned for $500, so your local shop isn't beating you too bad because a blow through costs a lot of shop/installer time.

You could build a louder one for 5k. A pair of BTL 18s, some component sets, and a couple crown amps would bring the house down. Literally.

Maaan that looks so d*** classy! Great work, especially with the wrapping. I would have had a crossover where the tv is, but you have to do what the customer wants...

The old school Hifonics Zeus Class AB was (and still is!) a Legend. The amp was rated for 600-ish watts RMS (into 4) but made over 900 at (2 Ohms). That only tells half the story though. If you're ever able to hook that bad boy up to a good efficient set of subs, you will see what I mean! Can you take pics of the amp and the card slot please? I have a friend with two working Zeus and one blown one...

You should start doing themes for your bailouts lol

Nobody vacuum seals boxes; that would pull the woofers' motors into the gap. Done properly, boxes are air tight though and will wheeze a little when the subs are pressed in slowly.

So your saying just cut out the whole top back behind the seats? Would I need a special box or a regular one and do I want them facing up? Heck no man. Just cut a hole big enough for the port.

You,ve never heard of a sealed box dude? Damn now I feel old lol.

In my Dreams: AA-12 M240G TAC 50 Real Life: Rock River AR Smith and Wesson MP 40 Saiga-12 (with tasteful updates lol)

Damn man that's messed up. Don't worry, they will put them in a prefab box on a sony xplod and blow them in 2 weeks.

It looks good. I would take that port out of the corner and place it in the middle of that open space. Your 2:1 should sound good depending on what you tune it to. With a relatively large ported volume, it will want to have a large low bass spike. You may have to experiment with reducing your port length for a flatter response, but just build it already lol.

You're being lazy lol. You're asking questions that you certainly know how to figure out on your own. It sounds like you know what you're getting into, so good luck!

Hey you're on matlab, you must be an engineering student lol. Bandpass are known to be louder than ported or sealed, but the group delay can be higher which some view as muddiness in the bass. I say you can't hear group delay if the subs are banging your ears apart. 2:1 can be appropriate, but it will depend on your sub. WinISD is pretty good. It gives you a lot of variables to play with in calculating, just be ready to convert.

Lolz this was an enjoyable post. I have a pair of double magnet 15s laying around giving me the same headaches. I'ma throw that shit away when I find them. Seriously, does PSI do custom coil orders? Any psi people on here?

x2 Plus, depending on your MY, you may already have 3 ways in that BMW. A good three way definitely sounds better than a two way for the same reasons a coaxial sounds better than a fizzer type speaker. If budget is an issue, you may want to select your drivers (don't worry so much about brand; just get the best you can) and build your own crossovers for them.

check your speaker leads with a meter...

Vented boxes definitely get louder and can get deeper inside the car (if designed properly), but you have to look at your speaker to see what kind of box it likes. There is a factor called the EPB (efficiency bandwidth product) that comes from the fs (resonant frequency of the sub) and the qes (electrical damping factor). The EPB is the Fs/Qes. If this calculated number is less than 50, then your sub may like a sealed enclosure. If it is above 50, then don't even think about putting that sub in a sealed box. Do yourself a favor and get a proper ported box design. Your sub will thank you for it (but your trunk might hate it lol)... Also, google 'roll-off characteristics for sealed enclosure' and see why a sealed can sometimes make deeper bass.

Brutus FTW

Make the port square. This is the closest approximation to a circle that you probably feel like constructing out of 3/4 inch wood lol

Lanzar Optidrive 1232Ds are cheap and sound awesome for their price point.

How about a pair of these: http://www.sonicelectronix.com/item_9931_Pioneer-Premier-TS-W5102SPL.html

All things equal, the rounder the port the lower the surface drag inside the port. The lower the drag inside the port, the louder the sound coming out of it. Tuning is a triple ratio between the air mass in the port, the area of the port, and the volume of the box. Any port can be tuned to anything provided the ratios are correct.

Here is an enclosure I built for a buddy of mine. It is for 2 cheap 12 inch Q Power subwoofers that look suspsciously like the kicker comps. The box is 2.0cf per sub tuned to 28hz. The port is 8x8 inches for a total of 64 square inches of port. It is surprisingly efficient and plays pretty low: The port prior to assembly Portage Notice the baffle brace built into the port Pre hole cut Not bad for 2 28 dollar subwoofers lol!

A brand new (w/ warranty) Audiopipe AQX 35001 for $550 shipped