Mixing and Mastering Audio are two independent yet related stages in audio production about which many people get confused and find difficulty understanding their differences. Both stages are important however one needs to understand them separately and have enough knowledge to get to know what they both add to the production process.
WHAT IS MIXING?
Before we get into the explanation of what Mixing is, let’s take a look at the overall music production process from start to end. Writing music consists of producing and recording multiple elements such as drums, vocals, basslines, melodies, and sound effects.. In general, when more than one track are added to the project, they tend to overlay and mask each other leaving less room for each sound to be noticed independently in the stereo field, thus making the overall project busy and muddy. Therefore, a procedure of assigning space for each element to sit in and having elements take certain shapes for that space, is what mixing is all about.
The very first aspect of mixing that comes to mind is gain structure or volume balance. Since we are dealing with multiple tracks, one tends to adjust the volume of each so to have balance. For example, you might want the bass to be louder than the chord, or the vocal more prominent than the snare drum etc.. This aspect of adjusting volume is both subjective and objective and need to be controlled within the borders of scientific limitations. But how can you adjust the volume of your elements if they are not yet cleaned and filtered? That’s a big mistake and this takes us to the technical side of Mixing.
The process of cleaning each element of unwanted frequencies and audio information consists of EQ’ing and Filtering, as well as Sample Editing and Dynamic Processing. This is when you make sure that each sound can take a specific shape by inhabiting their own frequency areas and enhancing them, eliminating unneeded frequencies, gaining headroom, and avoiding masking. This process focuses on one of the three dimensions in mixing.
3D Mixing is the process of working on the three dimensions in that sonic field: Up/Down, Front/Back, Left/Right. The frequency engineering i have discussed earlier tackles the Up/Down dimension where low, mid, and high frequencies occupy their spaces without interfering with one another. The Left/Right dimension is simply adjusted by the process of Panning, that is, working on the left, right, and center balance of each element, and finally the Front/Back dimension is adjusted by the volume of the element. Elements can be pushed to the background or to the front by adjusting the volume levels or by using audio effects such as delay and reverb, or by the process of sidechain compression.
Other aspects of Mixing involve Dynamic Processing, which controls the dynamic range of audio whether it is oscillated or recorded. By dynamic range i mean the difference between the loudest and the quietest peaks of audio. To make this easier to understand, consider someone recording vocal. If he moves a lot or sings in a way that is different from one take to another, then the result will have a lot of volume fluctuations, and this is where Audio Compression can be used to control the dynamic range of this recording and have the vocal sound stable and normalized. This is just one aspect of dynamic processing out of many that include limiting, gating, expanding and so on..
WHAT IS MASTERING?
Mastering is a broader process and considered to be the final stage of both audio production and album production where each song or each album is taken as a whole. Yes, each song consists of multiple layers or multi-tracks, and an album consists of multiple songs. When it comes to a single song, mastering becomes the process of “adding make-up to a beautiful lady” as Robert Babizs said during his masterclass at Per-vurt, and when it comes to an album, mastering becomes the process of normalizing all songs and have them ready for pressing or broadcasting.
Mastering a song doesn’t fix mistakes that happen in the mixing stage, however it is going to add slight adjustments primarily to the EQ, compression, limiting, and stereo enhancement. If a mix is bad, a master won’t sound good, it is no magic! However, if the track is well mixed and has enough headroom for the mastering engineer to add his magic, then he will surely take it to another level. Note that mixing involves mastering.
When you are mixing a sound or a layer, you are already mastering that layer independently, and finally, when all layers get rendered together in one track, they would then be mastered to give that one final track the maximum sound quality it can get. Remember, the mastering engineer has no access to the individual layers or elements of the song, so if the mix is not accurate, he can not dive deeper into the sound and fix mixing mistakes.
Mixing and Mastering are relative to each other. The mastering engineer’s primary goal is to provide a high fidelity, high clarity, professional sound that can be enjoyed by listeners on any source. If we go back to our juice analogy, mastering would be adding extra toppings.
Mastering an album involves the process of leveling all songs so that they be coherent, and rendering that album under specific settings using very specific analog gear to make sure the album would be professionally pressed on vinyl or cd or be ready for broadcasting or for digital download. Such processes include Bit-Depth Reduction, Dithering, Sample Rate Conversion, Sequencing and Spacing.
TO SUM UP
Mixing and Mastering are two very important stages of audio and album production. They are different yet relative and related. A Mixing engineer and a Mastering engineer can be the same person. Both processes require a lot of critical listening and visual attention, and both can affect the song dramatically
- The Mixing Engineer has access to every single layer of the song, the Mastering Engineer doesn’t, rather he works on one final master. This is why mixing takes more time and is much more expensive than mastering
- Mixing and Mastering have similar procedures, both can use EQ, Compressors, and Limiters
- Mixing balances individual instruments together, giving each sound its place in the sonic dimension after going through surgical frequency engineering, sample editing, and dynamic processing. Mastering balances the whole song and gives it the final make-up
- A Good Master requires a Good Mix
- A Perfectly mixed track might not need mastering
- Mastering has to do with having an album ready for pressing or broadcasting. It also has to do with leveling all tracks to sound coherent within the album