You can get decent results if you use a large-diameter hose between the accumulator and the nozzle and keep the effect valve right up near the nozzle. Not only do you get better throughput with a larger hose, but the hose itself acts as part of the accumulator. For Dance Dance Immolation we have a long run of fat hose between the effects aimed at the players and their accumulators, I think it's 3/4", (Note: big, long LPG-rated hoses are EXPENSIVE!) the accumulators are four BBQ-size tanks, and our tank pressure never exceeds 130 PSI or so. If you're going to be firing the effect a lot, you'll need tank heating just to maintain initial pressure for long; it's surprisingly tricky to get tank heating right without needing to pay constant attention to it.
Since you said you were looking for "bang".....if you're looking for the most percussive effect given the available gas flow, pay attention to nozzle design- a nozzle with a flare on it helps the gas slow down as it exits, making it easier to ignite but more of a "whoosh" and less of a "thump!"

Howdy George - I rather doubt that you'll be pushing that much pressure unless you have a really large surface area of gas to draw from. Yes, utilize a manifold and have multiple fuel tanks feeding your accumulator tank(s). Use those big red plastic tubs from Smart & Final to keep your supply tanks from freezing up (also good for keeping your beverages cold in the water since it won't stay warm if you're burning lot's of fuel). Depending on your application and design you should consider using more pipe and less hose. I have a five or six made 3/4" LP Gas hoses made by Parker rated at 350 PSI of various lengths if you want to come by to see what they look like just give me a call.