You effect the audio file directly with Audiosuite plugs.
Highlight a region or section of a reigon, choose a plug from the Audiosuite menu, get your settings as you want them, and apply the effect. This will create a new region containing the desired effect.
Audiosuite plugs are very much usable, just not in real time.
Plug-ins that are available as inserts are RTAS (real time) plugs.
Highly reccommend reading the
Plug-In's Guide .