A Guide to Mastering Music
What The Heck Is Mastering?
There is a lot of mysticism surrounding mastering. It’s often characterized as this secretive dark art performed only by a few chosen audio engineers in their inner sanctums full of ancient and mysterious equipment. While the best mastering engineers are generally well-respected professionals that work in specifically designed studios with high-end gear, the mastering process itself is not really that complicated. So what the heck is mastering?
The general answer is that mastering means preparing a final mix for distribution. The specific answer is that it means adjusting a mix’s tone, dynamics, stereo width, peak level, and file type. Engineers use many of the same hardware and software tools in mixing and mastering. The main difference is that in mixing, many tracks are processed separately and blended together to produce a single stereo track. In mastering, that stereo track is the only track being processed. A good comparison is furniture carpentry; mixing is building the table, mastering is applying the lacquer.
As I mentioned, many of the same tools are used in mixing and mastering, such as EQ’s, compressors, limiters, saturators, stereo imagers, etc. Tone shaping with EQ can correct imbalances in frequency, as well as creatively sculpting the tone to increase the emotional impact of the song. Compression can help control the dynamics of the mix, and give the tune cohesion and punch. Limiting is compression with a very steep compression ratio, which is useful in taming wild transient peaks. However, beware of overcompression, because that can reduce the energy and impact of the mix, introduce unpleasant artifacts to the sound, and increase ear fatigue when listening to the song.
There is some debate in the music industry over whether or not the mix engineer should mix with a stereo compressor on the master channel. It really boils down to personal preference and the experience of the mix engineer. Mixing with compression on the master channel takes some time and practice to get used to, but in my opinion is well worth it. Some people prefer to leave compressing the master channel to the mastering engineer because they are well trained and have the right gear to do the job. Either way is acceptable, but be aware that if you compress your mix before sending it to the mastering engineer, they will not be able to undo the compression you’ve already applied. Also, NEVER limit your mix before mastering. That is one of the few cardinal sins of audio engineering.
Saturation is an interesting technique because it affects the tone and dynamics of a track by mildly distorting the signal in a way that sounds pleasing to the ear (if done correctly). There are many different methods of saturating a signal. You can gently overdrive a tube or solid state circuit, record it to magnetic tape, cut it onto vinyl, or use software emulations of any of these methods. Each saturation method affects the tone and dynamics differently, so it’s important to choose the proper method (or methods) carefully. We’ll explore the intricacies of saturation in a future blog post, but suffice it to say that saturation is an extraordinarily important tool for imparting color to a mix.
Adjusting a mix’s stereo imaging is a tricky task, but can be greatly beneficial if done properly. Manipulating a track to sound wider can make it seem more immersive. This can be accomplished with stereo widening plugins, which often come with multi-band controls to independently process different frequency ranges. EQ’s and compressors with mid-side capability can also increase the apparent wideness of the track by making elements on either side of the stereo image pop out more.
As exciting as wide tracks may sound, there may be some times where a track may need to be narrowed, especially in the low frequency range. Generally speaking, everything under 100 Hz should be in the center of the stereo image, for a number of reasons. Low frequency sounds are less directional, so it will be harder to tell where a low frequency sound is coming from. Low frequencies also generally have a large amplitude, so panning it in the center spreads out that energy between the left and right channel, giving your mix more headroom. This is especially important when mastering for vinyl, as too much low end on one side may throw the needle out of the groove entirely. Furthermore, it is the general consensus of the audio industry that low frequencies kept in the center helps ground a track.
Mastering may also require some level automation. This may take the form of a fade in or fade out, if that is appropriate for the song. It can also be some mild fader riding to either increase or decrease the dynamic contrast throughout the song. For example, it might help the chorus to pop if the volume of the verse is lowered slightly. However, it is important to keep the dynamics within a reasonable range because your song may be played back in any number of noisy environments. A general rule of thumb is to master the song so that the listener does not feel the need to adjust the volume at any point because of level changes in the song.
That covers the basics of the processes that are accomplished in mastering, but you might still have a lot of other questions about mastering, so I will try to touch on the main ones that come up often.
Do you have to have your songs mastered? - No, but mastering is almost always beneficial to varying degrees depending on the song material and distribution method. If it’s a simple song that will just be going up on Soundcloud to share with your friends and family, it might not be worth the money to have it mastered. For anything you plan on selling, I would highly recommend mastering.
Do the mixing and mastering engineers have to be different people? - No, but there are benefits to splitting up mixing and mastering. Some engineers specialize in one task or the other, and may be better suited for their specialty. Also, having two different people analyze and process a song in two different studios can help correct for any problems the first person may have missed, either by their own fault or because of an issue in their monitoring setup.
I mix my own music, can I also master my own music? - Yes, but a professional will be better suited for the job. If you do master your own music, I would recommend using a light touch to avoid butchering the music you’ve worked so hard on.
What about automated mastering services like LANDR? - These are an option, but the consensus in the industry is that these automated systems are best used for demos. Their value lies in their cost effectiveness and their speed, which is usually just a few minutes. However, nothing beats a trained professional when it comes to fine tuning your tracks to perfection.
Does loudness matter? - Sort of. Dynamic consistency is important for the reason I stated earlier, to help the listener hear the song over whatever noise that may be happening around them. In the past, record labels pushed mastering engineers to make tracks as consistently loud as possible to make the songs stand out from other songs on the radio. However, the advent of music streaming services has mostly done away with this trend, as most of the streaming services normalize songs for loudness, so everything will be within a reasonable range. In fact, songs that are mastered to be extremely loud may end up sounding quieter on these streaming services, so it’s best to master your tracks however sounds best for the track and not to “compete” with other songs.
Hopefully this guide has helped you better understand the art of mastering. Be sure to check out our other blog posts for more helpful information, and if you need a project recorded, mixed, or mastered, please reach out to us at info@incandescentaudio.com!