The Dawn 510 speaker system I mentioned in my post was at least partly engineered here in Wichita KS and later sold and is now largely extinct. I have two sets I bought on ebay and put in all new speakers. This unit has a sound dispersion that is fantastic. It has a down shooting woofer with a crossover out to two satellite 5 inch speakers that face up and have dispersion surfaces that nearly equal the Bose L-1. Placed behind the singers there is very little problem with feed back, and you don't need any monitor speakers because the singers and players hear the same thing as the audience. It sounds silly, but I have used this thing in a gymnasium with over 200 people and did not even come close to max power, and there was no distortion. And I have had audience as close as 5-6 feet to the satellites in small venues with not any complaints about volume, even those 30-50 feet away. This system was way ahead of it's time and did not catch on because in the early '70's it was all about big everything. The whole thing including my amp/mixer weigh about 50 pounds, which is nice for an old guy like me.