Can someone please explain to me

Lestratcaster

How you hook up an AxeFx/Kemper live?

Like I see all kinds of rigs with pre-amps and stuff like that. I have read you can either use a Kemper for exmaple, straight into the PA at a venue if the sound system is great. If not you could run it out of a cab with an amp head as a "pre-amp"? 

This stuff really confuses me so if someone out there is already using this setup could they explain it to me in a simple easy to understand way?

As an example one of the guitarists in the band I play dep gigs for uses a Line 6 Pod Pro, a Laney Ironheart for the "pre-amp" and an Orange cab. 

Chalky

2 types of Kemper - original Kemper, or Kemper with built-in poweramp.

3 ways to get a Kemper to drive a speaker - a)original Kemper to PA, b) original Kemper to a separate poweramp and on to speakers, or c)Kemper with a built-in poweramp to a speaker cab.

So a) and c) are easy.  For b) you can use a dedicated poweramp connected to a cab, or you could use (for example), the fx loop return jack on a Fender HRD.