I am trying to put together a sound system for a float in a Mardi Gras parade. The float is roughly 15 feet wide and 40 feet long, holding 28 people. We will probably play all of our music from an ipod, but I would like a system that is loud enough for the float members and for the crowd to hear. (It doesn't have to overpower the crowd or anything, though.) The speakers need to be mountable, and the float runs on a generator (not sure what type or its specs). Other considerations are that it needs to be heard above a tractor that is pulling it, a generator, and the crowd. Any suggestions for type of speakers, amp (and your opinion on whether one is necessary), and stereo receiver/mixer. I'm trying to stay within a budget of $1000-1500, although I know that may not be possible. I know nothing about outdoor speakers or using a mixer vs. a receiver, so any help would be much appreciated. Thanks.