What if I told you there is a simple way to:

• Help your music connect better with your listeners.

• Ensure your music sounds consistently good no matter where or what it’s played or streamed on.

• Feel confident, knowing that you’ve done everything possible to make your music sound and feel the best it can?

I bet you’d want to know more. Welcome to the world of mastering audio.

It seems that everyone involved in music has an opinion on mastering. But what is it, why should you care, and should you master your own music or choose a great mastering engineer? Read on.

Why Should You Care About Mastering?

Think of your favourite songs. What do they have in common? They all evoke a feeling and make a strong emotional connection with you. All things being equal, most listeners won’t know why they don’t hit repeat on a certain song. They won’t verbalise that the music felt uncomfortable to listen to (too much sibilance) or that the song didn’t build to a climax (limited dynamic range) or that they just didn’t “feel it” (muddy low end that hampered the groove).

Good mastering resolves all these issues and brings a final stage of clarity to your mix, making it easier for your audience to connect with your music and then keep listening to it. With more music being released than ever before, anything that helps your music stand out is a good thing!

So, What IS Mastering?

Well … it depends. The meaning of the word has gone the same way as the definition of a record producer. It’s developed into a catch-all for much more than just creating production masters from a mix.  

Originally, mastering was a technical process - the last step before the physical manufacture of a record - cutting a vinyl lacquer from mixes on tape. EQ was applied to compensate for the limitations of vinyl, and a limiter was used to prevent the vinyl cutting head from being destroyed, but little creative work was done to the mixes.

Jump to the present day, and we have the somewhat controversial “stem mastering”, machine-based AI mastering (e.g. Landr or eMastered), and everything in-between.

Before we delve deeper into what mastering is (and isn’t), let’s see how some of the most renowned mastering engineers define their role:

“[Mastering] is the finishing school for the album project. It’s the last stop to get right any concerns that the artist, producer or label has with the sound.” Ted Jensen (via Atlantic Records website).

“Mastering is about trying to make that connection with the emotional message of the music easier for the listener to experience.” Bernie Grundman (via Red Bull Music Academy website).

“The purpose of mastering is to maximise the amount of musicality that’s kind of inherent in the tape that’s been mixed.” Bob Ludwig (via Performer Magazine website).

Enhancing the sonics, emotional impact, and musicality of the mix is a common theme among mastering engineers. But let’s not forget the less glamorous technical side that is crucial too.

The Technical

Here are some basic technical things a mastering engineer will do on most projects. Some of these blur into the creative:

• Remove any distracting noises (often clicks or pops) that are in the mixes.

• Top and tail each song (clean up the starts and ends, add fades where needed).

• Create pacing (gaps between tracks) for the album that feels good.

• Ensure the relative levels of different tracks on the album feel good.

• Ensure that the mix sounds consistently good on a wide range of playback systems (e.g. radio, car stereo, headphones, speakers, club PA).

• Take into account loudness norms for different formats (e.g. CD, streaming, vinyl, TV).

• Encode label copy (artist name, album name, track titles, ISRCs) into the production masters.

• Create production masters for different formats (CD DDP, vinyl pre-masters or cutting lacquers, Apple Digital Masters, other streaming services).

• Create and keep track of different mastering versions, including:

  • Mix revisions

  • Mastering revisions (and any outboard hardware settings)

  • TV mixes (no lead vocal)

  • Instrumental mixes (no backing vocals or lead vocal - very useful for sync licensing or re-mixes)

  • Single mixes (sometimes a different mix or shorter version)

  • Radio mixes (sometimes with swear words removed)

  • Cut downs (shorter versions for radio, singles, and promo)

• QC the final production master.

• Keep the project backed up and available at a moment’s notice.

Loudness - How Loud Is Too Loud?

Getting your master’s ear blisteringly louder than another artist has been a constant theme in commercial music - all the way back to Wurlitzer Jukeboxes. These days it’s less important, especially for streaming services: A really loud master on Spotify or Apple Music will be simply be turned down, negating any perceived advantage - the so-called “loudness penalty”.

Although there are recommendations for different platforms, these regularly change. The main thing is to do what sounds and feels right for the music. A punk album will generally be mastered louder than a jazz album.

The Creative

The most important skill a mastering engineer brings to your music is perspective, and a mindset focused on the big picture (the emotional impact of the song) rather than the intricate details that mixing involves (e.g. the delay time on the guitar solo).

When I’m mastering a song, I’m hearing it for the first time and mentally comparing it to thousands of others I’ve heard in my studio whilst mastering other projects. At this stage, I know what “good” sounds and feels like, and I’m able to bring that knowledge to the song I’m working on. 

If you’ve watched any YouTube videos about mastering, you get the impression that every mastering project involves tape plug-ins, wideners, exciters, enhancers, mid-side processors, parallel this, multi-band that. But many mastering sessions are based around simple EQ to tidy up the low end, a de-esser to keep sibilance in check, and a final limiter (or two). And sometimes, when the mix sounds and feels amazing, doing nothing creative is the best thing for the music.

All that being said, with more people working from home studios with less than ideal acoustics, some mastering sessions can get pretty deep, and in those instances when a re-mix isn’t possible, you use whatever tools you need to get the results your client wants.

Using some of the incredible plug-ins available, it’s possible to:

• Change the level of the lead vocal.

• Make a track feel more urgent or relaxed by using multi-band processing on the low end.

• Add weight to certain elements in the mix (e.g. a snare drum).

• Widen certain elements in the mix (e.g. guitars).

• Change the width of the low end, so it feels credible to the genre it’s in.

• Reduce the amount of reverb in a mix.

Can You Master Your Own Music?

Many people do (some very successfully), and it is worth having a go - it’s fun, and you’ll learn what the process can do and what its limitations are.

But would you cut your own hair, given the choice? For an important event, perhaps not!

I read somewhere that Ken Scott (famous Abbey Road and Trident engineer) was required to work in the mastering room at Abbey Road before he was allowed to mix records to ensure he learned about the problems that could happen if you gave the mastering engineer a bad mix to transfer to a vinyl lacquer.

So, even if you’re not planning to become a mastering engineer, knowing something about the process and how it can help your final product can only be a good thing. A couple of things to be aware of: Using the same speakers and room that you mixed in is not ideal for mastering as you’ll find it difficult to hear the anomalies of the room as you’re still working in it. If you do master your own mixes, try and put some space between finishing the mix and starting mastering. Even a few days can help you get out of the mixing mindset into the mastering headspace.

The Future Of Mastering

Is machine AI mastering sites like eMastering and Landr the future of audio mastering?

They’re certainly quicker and cheaper than hiring a human. Does that mean they’ll end up replacing professional mastering engineers? Not any time soon! Whilst they definitely have their place, they also serve a different customer base with different needs: One is like getting a bespoke “made-to-measure suit”, and the other is very much “off-the-rack”.

And what about stem mastering (creating a master from stereo “stems” of the mix. e.g. drums, bass, guitars, keys, vocals)?

Some would argue that this amounts to mixing, not mastering. I’ve mastered several albums from stems, and it worked out great because the mixes were so good, I didn’t need to open the stems at all. My feeling is that the more choices you have in the mastering session, the harder it is to focus on the big picture and the less value you bring to the project as a mastering engineer. Your mileage may vary - let me know what you think.