like above, tilt it towards the listener. usually means tilted down if above the screen, and tilted up if underneath the screen. recommended height would be as close to the screen center as possible. I've always preferred mine to sit on top of the screen, but if your screen is a little higher than ideal, then under would probably be the better choice. ideally, the fronts and center should be around the same height as well. but I've always tried to match my front speakers to the center speaker, not the other way around.