Marck,
Just in case the multitude of answers aren't enough, I'll add to the confusion by putting my 2 cents in.
I use a pair of ElectroVoice EV SXA360's
http://electrovoice.com/download_document.php?doc=1413 . They are extremely well built speakers with the power to handle large areas. They are a little pricey but the sound is great.
They are more compact than my JBL EON 15's were and yet still pack more punch. When I put them together with my ElectroVoice EV SBA760
http://electrovoice.com/download_document.php?doc=1430 they really kick.
The sub has a built in crossover, but I use the one in my DBX DriveRack PA.
But if you're trying to stay lightweight, then just leave off the sub and you'll still get a lot of bass
Richard