“Mastering” seems to be a confusing subject for many. What is it and is there some sort of technical voodoo that makes certain records sound better than others?

By definition, mastering is the term most commonly used to refer to the process of preparing and transferring recorded audio from a source containing the final mix to a data storage device (the master); the source from which all copies will be produced (via methods such as pressing, duplication or replication).

That’s a mouthful. To parse this out, mastering employs 3 separate processes:

  • making the music LOUDER,
  • creating consistency across an album, and
  • preparing for distribution

Making the Music LOUDER

Everyone wants their music to be the loudest. This is achieved through a process called compression or limiting. When music gets compressed or limited, it becomes exactly that: compressed or limited! While louder music sounds like a great thing, special care has to be taken. As the music gets louder by being “compressed,” the dynamic range gets squashed. When taken too far, the result is a horrible, non-musical sounding track that is overly distorted and smashed to smithereens (for a good example of this, simply Google “Metallica Death Magnetic Mastering”).

If this is true, why would anyone want to “limit” their master? Psychologically, louder music tends to excite us. To illustrate, back in the day when people actually purchased home stereo systems, stereo stores used to have the more expensive gear turned up slightly louder (not loud enough to make a noticeable difference, but just enough). Using this tactic, the consumer would consistently interpret the “louder” system as “better” or “higher quality.” Similarly, too little compression on your master will make your album sound small, not translating nearly as well when compared with tracks from other artists.

The right mastering engineer will know where a good trade-off lies with limiting dynamics for volume. There’s an art to this process. Any good mastering engineer not only has the appropriate tools to measure dynamic range, but also has a great “feel” for what is right on the edge vs. teetering over.

Consistency Across an Album

Consideration has to be made for how the individual tracks work together when played one after another in an album sequence. Is the sound consistent? Are the levels matched? Does the collection have a common “character” and play back evenly so that the listener doesn’t have to adjust the volume or EQ settings?

What this means is that the mastering engineer doesn’t simply make one preset and use it on every song; they have to tweak each song in context with the others. The goal is to reconcile the differences between tracks while maintaining (or even enhancing) the character of each of them, which will most likely mean different settings for different tracks. Along these lines, the job of a mastering engineer typically involves making very small tweaks to the EQ and stereo image of the track(s) to help the song “punch” as much as possible. While the typical credo of great mastering engineers is to not “change” the sound achieved by the producer/mix engineer, very small tweaks can take a good mix and make it great!

Preparation for Distribution

The final step prepares the song or sequence of songs for download, manufacturing and/or duplication/replication. This step varies depending on the intended delivery format. In the case of a CD, it can mean converting to 16 bit/44.1 kHz audio through re-sampling and/or dithering, setting track indexes, track gaps, PQ codes, and other CD-specific markings. For web-centered distribution, it means adjusting the levels to prepare for conversion to AAC, MP3 or hi-resolution files and including the required metadata.

Mastering Before and After

Confused? Don’t be. Simply put, mastering is the final “quality control” point before the album is mass produced. To illustrate the sonic difference good mastering can make, here is an example of one of my artist’s tracks before and after:

Pre-mastered Version:

Mastered version:

As you can tell, not only is the music louder in the mastered version, but the bass is more full and the entire song is more in-your-face. That’s what good mastering can do to a track: take something that’s working, and make it really “pop!” Before sending your little babies off to the cheapest “mastering guy” you can find, do the same work you did when finding the right producer: take the time to get references, listen to what work they’ve done previously, and start a conversation with them (or talk to your producer about whom they like to work with!).

If you’re interested in learning more about music production, be sure to signup to receive email updates; if you’re looking to bring your music to the next level, drop me line! I’d love to talk about what you’re working on and discuss ways to elevate your game. I’ve spent the past 2 decades developing relationships with several brilliant mastering engineers, and can steer you to the right one and help get you a great rate.

Special thanks to the ever-creative and talented Kelly Taylor (http://www.heyitskel.com) for the above examples.