I'm certain others can be more clear about this, but I can tell by the way you are wording your question that you dont really understand what Mastering is. I mean, a preamp is used for recording and imo has diddly to do with mastering, so why list it.
Wait a bit and they'll be along shortly.
For mastering, I would consider an outside Mastering Studio, like Massive Mastering. 8-)