What would the best way to play through an amp modeling system/multi-effect pedal? I have a Line 6 POD X3 Live and a Digitech GNX4 but I want to buy a PA or power amp or something to play it through without getting the sound of two amps interfering with eachother and all that **** as if you were playing it through an amp which I have been.

I was told playing them through a PA or Power Amp was what they were made for but I dont really understand how this works since I have had no experience with them at all. Can somebody help please?
its like a pa but looks like an amp. all it does is amplify your guitar signal no coloration no interference. and with the higher end models you can have your bass player and vocalist plug into the same amp