I was going to suggest this too. It'll give you more than enough power to fill the room. Another possibility (though it makes me cringe a little) is a guitar amp which you can easily find for cheap in a pawn shop. Lousy sound quality for general music, but boomy, rugged and portable should you ever want to use it outside. (and hey, you could always jam on it)
Actually, if you get a mixer to use with the active monitors, you could even patch through the guitar amp as a makeshift sub. Once again, it won't sound great, but most kids just care about volume anyways.
Actually, if you get a mixer to use with the active monitors, you could even patch through the guitar amp as a makeshift sub. Once again, it won't sound great, but most kids just care about volume anyways.










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