Orban are well known in the broadcast field for their audio processors. Robert Orban the man behind it the company has co-wriiten a long running series of booklets on "Audio Quality". The 2008 update of Maintaining Audio Quality in the Broadcast Facility is online at the moment. Grab a copy if your interested in the factors that influence audio quality in your studio. It's written from a broadcast perspective but the principles apply to the smallest project studio.