All major concerts and most professional venues are in mono. The only place you're going to achieve a stereo effect in every part of a large venue is in BizzareWorld. It's just not possible. Although I too fall prey to the myth that it MUST be in stereo, intellectually I know that the stereo effect I achieve using two powered monitors, is primarily for me (and a handful of folks in the 'sweet spot'). Still, it's a great way for music stores and speaker manufacturers to get you to buy two of everything.

Trust me (he said slyly ), 'bridge' that stereo power amp and send a mono signal to as many speakers as you want (placed strategically all around the room) just as pro acts send a mono feed to their sound engineer.

Don't forget about the diminishing effect of stereo as you get further away from the source.

chas

Ps: Most of what I say is sometimes true.