Which StudioLive desk would be best for a rock venue?

Depending on the number of inputs required, guitarguitar would recommend either the StudioLive 16 Series III or the Presonus StudioLive 24 Series III for small to medium sized venues and the Presonus StudioLive 32 Series III for larger venues or venues where many inputs are required, for instance where bands with brass sections often play.

What is 'Fat Channel'?

Fat Channel is a section within certain StudioLive desks which is available on every channel and aux bus and is comprised of a compressor, limiter, gate/expander and four-band parametric EQ.