I just want to see what everybodys oppinion is on a bandpass enclosure. I was wondering this because my friend has just given me his box along with 2 12"s, a bass module and all the wiring I need. Should I keep the bandpass box (it looks pretty clean) or should I go with a closed enclosure. By the way the subs he gave me were 12 inch lanzar MXW12D. Not the best sub but i cant complain they were free.
Every experience I have had with bandpass enclosures is that they were WAY boomy and sounded like crap. But I haven't heard a properly setup bandpass enclosure. All I have heard is pre-fab ones with subwoofers that were just put in there. Bandpass enclosures are very difficult to design properly, and much more finicky in what works well in it. This is why my experiences have been so bad with them. Because of this, I would recomend getting a new enclosure. I'm sure the subs will sound MUCH better in a sealed, or even ported enclosure designed specifically for them. But since you already have it, why not hook it up and see what you think? Maybe you will like it. And that's what is really important and may save you some money.
-------------
Bandpasses can sound really good in the right environment. If they are tuned to the woofer(s) properly and if they are tuned to the vehicle, they will create SPL like nobody's business for their relatively small size and within the port frequency range. The key is tuning the enclosure to match the frequency of the car's cabin. But, since most people do not have the equipment or time to do this, and since most pre-made bandpass enclosures are actually pieces of crap that are not designed for the drivers but are designed to show off the speaker cones or to trick the buyer into thinking they are getting more bang for the buck (hey dood, look, this thing has TWO 12's in it!) they end up sounding like boomy noise makers.
Try it. If you like the sound, keep it. If not, get the specs for the woofers you have and biuld (or have built) a new sealed or ported enclosure.