First, be sure to clean any imperfections left in the audio file: Clicks, pops or other types of artifacts might become more noticeable after mastering.

While these problems can be adressed during the mastering process, it’s always better to work on a finished files without any issues of this kind.

If you plan to work with a mastering engineer, getting in touch with him prior to the session is always a good idea: Most are well versed audio enthusiasts that will often provide valuable advises to get your tracks ready for mastering.

Check with him that the mix quality, global balance, file format and specs (resolution, sample rate, …) meet his expectations.

During the mastering process, EQs can be used in multiple key points of the signal flow.

It’s common to add a high-pass filter to keep ultra-low frequencies from straining the listener’s speakers, and prevent excessive low end from triggering dynamics processors like compression and limiting.

EQ is also used to sculpt the overall frequency balance of the mix, as well as tailor the response of other processors in the chain.

When it comes to EQ, the point is to subtly correct any issues that stand out, bring out the best in the song and aim for a good overall tonal balance.

Follow this link for some great and free mastering EQ plugins recommandations !

Compression is another key component of the mastering chain to control the character of the mix’s dynamics and ‘glue’ all the elements together.

Good masters maintain a delicate balance between headroom, loudness, dynamics and transients.

Compressors allow to manage these factors and enhance the mix with punch, definition and control.

Multiband compressors can also be used for even more precise dynamics control by giving you the ability to sculpt each range in detail, using different characteristics and settings for each frequency band.

Here are some free compressors plugins that you can use for master compression.

Limiters are used in mastering to ensure that the finished audio file will never cause clipping.

They’re also used to bring up the level of the mix to a volume that’s suitable for the release medium (digital, vinyl, …)

By setting the ceiling for the loudest peaks in the mix, you can increase quieter parts of the mix to get the desired dynamic range.

A good advise is to aim for -1dBTP (TruePeak) and around -14dB LUFS.

Read more about loudness management in this article !

Several techniques can be used during the mastering process to enhance the spatial qualities of the mix. These range from subtle stereo expansion to control of stereo information in the low frequencies.

Stereo processing in the mastering chain is much subtler than the stereo widening techniques used during the mix.

Mastering setups often include elaborate metering hardware or even tape machines in addition to the elements covered before:

While high-end mastering studios usually prefer expensive outboard gear, there are many software mastering tools made specifically for the job.

But the most important remains a set of great monitors in an acoustically treated room: Listening environment is crucial to get a good mastering.

For digital formats, mastering also includes ‘dithering’: Dithering means introducing noise to the signal at a very low level below the audible range to improve the accuracy of sample rate and bit depth conversion.

Dithering occurs in the software domain before export, so this last step in the chain is applied in the DAW.