Some advice on compressors

[RedAl]

I'm about to replace my tired old compressor with a new one with a tank but i'm a little confused on the specifics of how these work.

My current compressor doesn't have a pressure operated cutout so is either on or off with the pressure at the brush adjusted by adjusting a sprung valve in the bottom of the moisture filter.

I'm considering the AS196 listed here.
http://www.everythingairbrush.com/ac...AS_Series.html

This states that the compressor will run until it reaches 57 psi before automatically switching off.

My question is when I want to work at lower pressures how do you adjust the pressure down? Is it a case of using a similar regulator and wasting the excess air or can the pressure at the brush be regulated another way ?