This book deals with digital sound processing for audio mastering, entirely inside a computer, ITB, In the Box. ITB mode has been chosen for various reasons. The computing power of today's computers allows a high level of accuracy and calculation. These computers are now within anyone's reach; such a text may help the reader make things that only a few mastering studios, provided with expensive equipment, could have done before. Nowadays, a home studio can produce good masters. If we consider the parameters and take the precautions to avoid degrading the numeric signal, our master can compete, quality speaking, with any commercial product. Do not be astonished if you find a copy of this book in a mastering studio, however. The purpose of this book is to analyze and experiment with the various elements of this post-production stage. The reader has the tools to analyze the sonic content and make the right choices for the signal processing within a DAW Digital Audio Workstation.