To be honest, if protability is not an issue, i’d go for a second hand setup off ebay. 2 tops and 2 subs, matched. With either a 4 channel amp or 2 2 channel amps and a crossover. It sounds like a lot, but you should be able to pick stuff up fairly cheap if your patient. Peavey are affordable, you might find some even better deals out there too.
2 15″ tops will simply not cut a 150 person venue, especially outside.
I recently witnessed a mobile DJ do a party, probably about 70 people there. He had a similar setup to what I describe, and it was adequate. But he didnt match the tops to the subs so sound was a bit off. With a bit of proper tuning it wouldve sounded loads better.
Its true to say i’m a bit of an audiophile though, no-one else there cared.
Seriously, rent a PA first. It’ll probably set you back £100/£150, thats a fair cut of your wage, but the advice you’ll get on setting up the system will be forever invaluable. Nothing can come close to a good rig setup properly. It is not simply plug and play.
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