There is one brand that Rang in my head in reply to your question, that being HK AUDIO. I will admit that we no longer use the brand ourslves having upgraded to a mackie rig, but HK AUDIO make fantastic rigs, for fantastic musicians, who aint fantastic scientists, Basically, what they refer to as their "active systems" are amp built in jobs, only drawback (if you can call it that) is the need for a seperate UNpowered mixer of your choice, then you simply wire your mic's, instruments etc into the channels as norm, run your two output leads from the desk to the powered unit,usually sub on the floor, and two leads from that in to the two speakers, plug in the power and play! simplemo!
We used the HK L.U.C.A.S for severel years without hassle, speakers are about the size and maybe a touch heavier than the average HI FI speaker, Don't laugh coz they pack a punch, or you can go up in size or down to the E.L.I.A.S as suits your needs or your pocket,
Anyway Thats my suggestion, WELL WORTH A LOOK, check out www.hkaudio.com for their range and hope this is help to you!