Audio mastering has been called a “black art” or a mysterious process that holds closely guarded secrets. This is really not the case, until you have heard high end loudspeaker systems in an exceptionally well controlled acoustic environment it is difficult to understand how the mastering engineer manages to make the improvements he or she does to sound.
A mastering engineer will receive files across the internet for an album and place them in his digital audio workstation time line. In the first instance he will listen to all track and get a feel for the genre and music that is present. During this time he or she will consider any audio problems that instantly jump out, these are noted and the music is listened to in greater depth.
The mastering engineer will use the tools at his disposal and make tonal correction and enhancement to the sound as each track plays. This can be done both digitally and in the analogue domain. Digitally the engineer will use plug in software to tweak the sound and in the analogue domain the sound will need to be re-recorded into the computer. It is essential that each track is at similar level to others on the album where required and consideration made for musical pieces that are naturally less musically dense or quieter pieces in general.
Careful attention will be paid to the beginning and end of the music to ensure that it starts and ends in a pleasing manner. The space between each piece of music is also important and it should be musically sympathetic to pieces that proceed and come after any given piece on the album.
A mastering engineer will consider each track on the album as an individual entity and yet have a wider view and holistically make decisions. The music must sound good in itself and in combination with other tracks that come before and after.
The main tools of the mastering session are the equalizer, dynamic range compressor and tools that allow manipulation of the stereo image. The goal is to find the most subjectively good sounding combination along with ensuring the music sounds good on many types of play back system.
Finally the music is committed to a master format such as CD, .wav or .aiff, AAC file or MP3 for online distribution and the enjoyment of the fans.