Here's another cool thing I just realized!
When you use the "loop out" & "loop in" method with a mixer, you can turn the keyboard speaker volume ALL the way off while you set the house levels and tone controls. Then, you can turn up the "monitor" as loud as you need it to be, WITHOUT affecting the mix in the house. This is BRILLIANT, folks. This really opens up a new world of precise monitoring from the keyboard location, without sacrificing anything from the house mix. And the beauty of it is that you only need ONE mixer, as long as it has more than one set of outputs! My gig at the shore has me using a house PA, and it's working out so nice. All the controls are at my fingertips, and the monitor volume does NOT affect the house volume. Very nice, indeed.