“Mixdown” is to adjust the volume and sound quality of each instrument in the song. It is like rasping on furniture. Because each musical instrument is played on a separate track, each unit can be raised and lowered. You can apply echo and other effects to songs. You can also adjust the pitch of the song.
Making the final polishing work is called “mastering”. Throughout the album, it is to match volume and sound quality so that you do not feel uncomfortable even if you listen to each song. It is like painting varnish on furniture. You can adjust the sound pressure using designated software. Currently, there are mastering service by artificial intelligence.