Allow me to help you understand who a Mastering engineer is. Also this is an excerpt from my book Essential sound principles.
The term “mastering” is most usually used to describe the process of preparing an audio mix for publication. This process involves various factors, including unifying a record’s sound, keeping consistency across an album, and preparing for distribution.
Mastering has several goals, including correcting mix balance errors and enhancing specific sound features, as well as taking a solid mix (typically in the form of a stereo file) and polishing it. This may entail changing the volumes of the tracks and general “flavoring.” Consider the difference between a good-sounding mix and a completed master that sounds professional.
This can include things like providing broad equalization, compression, and limiting, among other things. In the world of LP and CD replication, this is known as “pre-mastering,” but for the sake of simplicity, we’ll call it mastering.
Depending on the sort of anticipated playback environment, the engineer will listen to various levels between 70 and 85dBSPL. The frequency response of the ear is not linear and changes with the level of sound pressure. The mastering studio must be a sufficiently quiet listening environment to hear the quieter portions appropriately. Listening to the mix through headphones or an inexpensive sound system is also a fantastic way to see how it translates.
For more information buy the book Essential Sound Principles by Edison Muhwezi
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