Mastering

Difference Between Mixing Vs Mastering?

Mixing

The balance inside the song (vocals vs. drums vs. guitar).

Works with dozens or hundreds of individual tracks (multitracks).

Blending instruments, adding creative effects, creating space.

Mastering

Works with a single stereo mixed down file.

The balance of the whole song relative to the outside world.

Polishing, optimizing loudness, and ensuring system compatibility.

Mixing fixes a bad recording; mastering fixes a bad mix. However, mastering cannot save a truly terrible mix—it can only enhance what is already there.