What is Mastering?

“Mastering is a fine-tuning process that is done to the studio mix. It is the final step before duplication and your last chance to get everything perfect. Albums that contain music from a variety of sessions, studios, engineers, and producers need to be combined into a cohesive sounding package. Mastering is about album consistency and a sound quality that doesn’t vary from track to track. Tonal balance, fade in’s and fade out’s, sequencing, noise problems…. all of these things are dealt with during mastering. Frequency analysis and correction, noise reduction, compression, expansion, and equalization (EQ) are just a few of the techniques used to provide the professional quality heard on every major record label’s commercial recordings.” © Global Sound Mastering
“Mastering an album is an art, like everything else associated with music & recording. Contrary to many people’s beliefs, mastering isn’t the first step in the manufacturing chain. It’s the final step in album creation, and every album gains from having undergone it to one degree or another. Simply put, mastering is the process of making an album sound the best that it possibly can, transforming the individual works into a cohesive album that can stand firmly in the marketplace with its competitors. Since albums are often collections of musical works recorded at different times and under sometimes radically different conditions, mastering generally seeks to establish a uniform baseline for all the musical works so that they have a “family” sound or the ordered sound of an album. There are many factors for the mastering engineer to consider when preparing to assemble and master an album, such as:

  • the musical style of the material in relation to other albums of its genre, especially in terms of the existing expectations of listeners of that genre
  • the quality of the finished studio tracks
  • overall spectral uniformity of the individual tracks
  • the dynamics of the individual tracks
  • what instruments/voices are driving the loudness & dynamic contours of the individual tracks
  • the album distribution media
  • the needs & dictates of the client

Based on the consideration of all these elements, the mastering engineer then makes decisions on a song-by-song basis regarding compression, equalization, level matching, and other spectral enhancement processes as may be needed to produce the best-sounding overall album!” © Digicore Productions

Also, see CD Mastering by Bob Katz at Digital Domain

The Voodoo of CD Mastering is a site maintained by Aaron Lanterman, who’s made a semi-career of collecting all the information and links on CD Mastering available on the net.