But what is mixing and mastering and why should I care..??
Making music is an art that requires careful precision.
Mixing the art of taking all of the instrumental, sound effects and other elements that make a song and putting them together not only in a creative and artistic way but also making sure that it is technically on point by balancing out the volumes of all the instruments and removing all sonically annoying frequencies. Many listeners do not know that someone sat in a studio for hours and hours listening to each and every element of the song and fixing it and bringing it to point. Next time when you are listening to a song, listen to how the backing vocals pop in from the left of your earphones and the percussion comes in at just the right time and everything is held tightly together by the groove - that was a mixing engineer's work. Over all mixing is getting all the ingredients working together in a beautifully crafted dish!
Mastering is the final step before a song is distributed to stores such as Spotify, iTunes, Youtube, Soundcloud etc. and also for physical distribution. With digital distribution the lines between mixing and mastering also became blurry and for many, mastering is a mythical art only a few seem to understand. Mastering is like the final packaging. Imagine you are going to work in the morning, you have your headphones on and you are jiving to the music. Both your hands have a cup of coffee, one for you and one for your co-worker that you have a crush on. Suddenly, a song comes onto your Spotify playlist that is MUCH louder than the previous one and yours ears hurt, you don't know what to do but you tolerate this for 3 minutes. If you hands were free you would skip it within the first 10 seconds. Mastering Engineers make sure something like this does not happen, being the final ears on a mix - they enhance the beauty and art of it while also enabling the audience to have the best listening experience.