Wow...for once my hobby and my work intersects. Interestingly enough I seem to know little on both ends. Hopefully someone can help me out here. I need several speakers capable of extremely LOUD output with considerable bass. We need the speakers to be able to reach 140 - 150 dB!!! Sound quality is not an issue. We will be generating basically pink noise/static to simulate a rocket launch. Cost, however, is definitely a concern. We certainly can't afford to spend $1000/pair, especially when we need 4 pairs. Size is also a concern. We would certainly prefer a bookshelf size speaker, but I realize that is improbable considering the bass requirements. Perhaps a subwoofer/bookshelf combo might work, but it looks like a tower is needed. I thought those white van speakers might fit the bill, but funny enough, I don't know where to find them. Also...some cheap powerful amp suggestions would be good too...though it looks like I might have to go into the car amp world to get something that's crappy but with tons of power.