I don't know about wall placement, but perhaps horn loaded speakers would be something to look into, unless you have gobs of power (they will give you definition at both high and low listening levels, though not the best bass response unless you spend a lot on them). Newer models by JBL, models from AR with built in powered subs and the vintage Yamaha 1000 monitors (though I don't know if they would hold up to continuous loud play due to their age) might fill the bill. The Yamahas are one of my favorite vintage speakers and are quite efficient, though will also handle a lot of power. If you have a local studio or pro sound shop ask them what will work in your room. We also have a few members that have a great deal of studio experience and hopefully they can give you some good tips on modern speakers. Are the speakers going to fire the length of the room, or the other way around and what do you have to push them with? Also, what is the ceiling height and your budget?