Mastering is all about two things: the gear and the ear. While there is an abundance of mastering-grade software and hardware available these days, possessing both the ears that are sufficiently trained to take advantage of that gear, and the knowledge and experience required to effectively act upon what those ears are hearing, is another matter. If you have invested in professionally recorded tracks, and want them to sound as good as possible before releasing them to the world, I advise you to seek out a professional mastering engineer with both the ears and the gear to do your music justice. Even the most accomplished and successful recording and mixing engineers typically don’t master their own projects.
For less critical work, however, there are some relatively simple things that you can do to finesse your recordings — probably using tools you already have. Most DAWs come with EQ, dynamics and other plugins that can handle basic mastering tasks, and excellent mastering-specific plugins and bundles are available from numerous manufacturers, including Waves, Universal Audio, iZotope, Sonnox, Steinberg, Sony and Native Instruments.
In addition to editing and processing software (for the purposes of this article we’ll assume you are working “in the box”), you’ll also obviously need at least one pair of good studio reference monitors with adequate bass extension (at least down to 40Hz, though 20Hz or even lower is preferable for EDM and other bass-heavy styles), and a decent listening space that doesn’t significantly color the sound. Professional studio headphones can also come in handy.
Mastering an album involves numerous tasks, including editing and sequencing your tracks, adjusting their relative levels, inserting the optimal spacing between them, converting various formats to 16-bit/44.1kHz files, etc., but the following tips are limited to simply making your tracks sound better.
1. Less is Frequently More
The cardinal rule of mastering is that changing any single thing changes everything.”
The cardinal rule of mastering is that changing any single thing changes everything. For example, boosting or cutting a frequency by even a tiny amount can change the way other frequencies are perceived, and even small amounts of compression can affect stereo imaging and the overall balance of a mix.
It is exceedingly easy to overdo it when applying EQ, compression, limiting and other processing, particularly when the change results in an increase in volume. That’s because due to the peculiarities of human hearing we tend to perceive louder audio as “better” sounding than quieter audio. Consequently, whenever you increase the overall volume of a track by boosting frequencies with an EQ, using a limiter, etc., it is critical to match the listening levels when comparing processed and unprocessed tracks. Many plugins have output level controls, but you can also adjust the levels with your DAW or audio editor’s faders.
Once you’ve applied processing such as EQ, compression and limiting (assuming you do) and got the track sounding the way you want it, take a break and revisit the settings when you return. In many cases you’ll find that easing back on some of the processing, even slightly, sounds better to your refreshed ears.
Also, in most cases it is wiser to cut frequencies rather than boosting them when using an EQ. If you want to emphasize the low and mid frequencies, for instance, try cutting the highs a little to see if that achieves the desired result.
Finally, although it is possible to get impressive results using processors such as aural exciters, spatial modifiers, enhancers of various types, and even multiband compressors, they should be employed sparingly (if at all) unless you are very familiar with using them.
2. Compare Your Recordings to a Reference
Choose a recording that you think sounds great, preferably of music similar to your own, and use it as a reference. Does the bass on your track sound as full and well defined? Does the midrange sound “boxy” in comparison? Are the highs as present, clear and open sounding? Identify the characteristics you find most appealing in the reference recording and then attempt to emulate them, switching back and forth between the two as often as necessary. Just remember to match the listening levels for the previously mentioned reasons.
3. Consider Your Listener
How do they sound on other monitors, your living room speakers, consumer headphones, ear buds plugged into your phone, in your car and on your external computer speakers?”
Once you have done what you can to make your tracks sound their best, listen to them on different playback devices to get a sense of how they will fare outside of the studio environment. How do they sound on other monitors, your living room speakers, consumer headphones, ear buds plugged into your phone, in your car and on your external computer speakers? And if EDM is your thing, befriend the soundperson at a local club and persuade them to audition a track or two on the house system.
4. What’s Too Loud?
For years mastering engineers were pressured into making recordings as loud as possible so they would stand out from the competition. That mostly involved using compressors and limiters to drastically reduce the dynamic range, sometimes so extremely that nearly every sound was the same volume. The so-called “loudness war” is gradually subsiding, however, partly because these days music-streaming services and playback devices from Apple and other manufactures generally auto-regulate volume to maintain consistency, and loudness standards have been adopted by radio and television broadcasters.
If your tracks are already squashed so much that the waveforms appear as rectangular blocks, there’s little to lose by aggressive limiting. But if your music has a wide or moderately wide dynamic range, you’ll want to find an acceptable compromise between retaining the existing dynamics and squashing the life out of the track. This decision is usually made at at the limiting stage and the limiter is typically the last processor in your signal chain. Try setting the limiter’s maximum output level to either -0.5dBFS or -1.0dBFS and adjusting the input level, threshold, and other parameters to taste.
5. Master at the Highest Resolution
If your digital mixes were produced at a resolution higher than 16-bit/44.1kHz, master them at that resolution and convert the mastered files to the desired lower resolution once the process is complete. One exception to this is mastering for Apple iTunes Plus, which utilizes higher-resolution files.
6. Back to the Mixing Board
It is a mistake to imagine that all problems with a recording can be remedied at the mastering stage. Sometimes, it is actually quicker and easier to go back and address problems at the mix level, and sometimes that’s the only option, no matter how much of a hassle it may be.
I hope these general tips have been useful. For a comprehensive introduction to mastering, and audio in general, I enthusiastically recommend Bob Katz’s “Mastering Audio, the Art and the Science.”
Julian Ludwig é diretor do Pro Áudio Clube, produtora de áudio Jacarandá, Loc On Demand e Jacarandá Licensing. Trabalhou para empresas como: Guaraná Antartica, TV Gazeta, NET, Chivas Regal, FNAC, Prefeitura de São Paulo, Mukeca Filmes, Agência LEW’LARA TBWA, Agencia MPM, Agência Content House entre outras. Fez trilhas para programas de TV como: Internet-se (Rede TV), Você Bonita (TV Gazeta), Mix Mulher (TV Gazeta), Os Impedidos (TV Gazeta), Estação Pet (TV Gazeta), CQC (TV Band) Vinheta Oficial TV Gazeta, entre outras. Também atuou em vários longas e curtas metragens, incluindo mixagem em 5.1 e serviços de pós-produção.