Rex
Dignified but Approachable
A couple of thoughts (caveat: I don't own either system):
- You can't judge a monitor's maximum power or volume level by looking at the setting on the volume knob. That only tells you how sensitive the monitor is. The only way to know maximum volume is to crank it until it clips, then back off a hair and listen (instead of looking at the knob). It sounds like you have enough volume for your needs.
- Your mix sounded bright. Was it because your monitor is too bright, or because his monitor needs an overly-bright mix to sound "normal?" Or because FOH is too dark to begin with? Assuming your monitor was pointed at you, were you listening to his monitor off axis? That will make his monitor sound darker in your ears.
- I wouldn't expect the relative performance between the Alta and the RCF to change much in a band situation, but you'd have to listen to know for sure. You don't always get what you pay for, but when the price difference is this large, it's almost guaranteed that the more expensive speaker will significantly outperform the less-expensive one.