I still prefer a 15" woofer, a horn for midrange and a tweeter for highs..3 way systems are the best for full range sound.

I also use 12's with horns, but need a sub woofer with them..Keep in mind I am talking about full range sound but in dance venues..

The newest keyboard amp I own {Traynor K4], is set up nicely with a 12" woofer , a pair of 4 1/2" mid range speakers, and a pair of tweeters..It has 3 separate amps for this 3 way stereo amplification..The mids are super clear[great for vocals]..