Mastering music - step by step approach

By Rob Stewart - JustMastering.com - December 15, 2013


If you have found this article, you may be one of many who are looking to understand exactly what an audio mastering engineer does. I have written a few articles about this topic already, but this one attempts to document the process of mastering audio in a step-by-step approach that I typically follow for any project. I also go into some detail about the tools of the trade in case you are interested in getting into this field yourself. If you have any questions please ask me any time, via my contact page


STEP 0 - Client Needs Analysis

It all starts with you :)! Before I begin mastering your music, it is important to me to assess:

  • Your goals for the project
  • Your level of knowledge or comfort with audio mixing
  • Your ability or availability to make changes to the mix (for example, do you have access to adjust the mix yourself, or did you pay to have someone mix your music?)
  • How happy you are with your mixes as they stand
  • What you are expecting to accomplish from the audio mastering process.

After I have a good understanding of this, I can proceed with the audio mastering process.


STEP 1 - Critical Listening

Many people ask "why master my music?", and more specifically "why pay to have my music mastered?". The main reason is to have someone with experienced ears hear your mixes for what they are, and then reflect that back to you in case your mix isn't translating the way you intended it to. It is a very important quality control step in the process of preparing your music for distribution and broadcast.

A significant part of my work involves understanding what you intend your mix to sound like on any playback system, and then assessing whether you met that goal or not. If there are elements of your mix that are detracting from what you were trying to accomplish, I need to call them out to you so that we can address them in the mix. For example, are there issues with equalization? Over compression? Are there problems that will cause issues during broadcast such as significant distortion or poor clarity?

To do this effectively, I use the following tools:

  1. A high quality, acoustically treated room designed for critical listening.
  2. A high quality, full bandwidth (20Hz to 20kHz), high dynamic range reference playback system that has been calibrated to play music as cleanly and accurately as possible.
  3. My ears of course! (my wife claims that I have "selective hearing" however I can assure you that my ears are highly tuned to audio and music)

Having these tools allows allows me to hear your whole mix, all of the good points and also any elements that can use improvement. They also allow me to fully trust what I am hearing.

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STEP 2 - Diagnosis

Based on my analysis, I determine what the song needs. For example:

  • is your mix okay as it stands, or do I need to ask you to submit a new mix file, first, with some changes?
  • what can I do to enhance the finest points of your mix, to make it even more energetic and more musical than the original?
  • what is the minimum amount of processing needed to accomplish this?


To do this effectively, it goes back to the same tools mentioned in Step 1, plus a fair amount of personal judgement. As you may have read in my other articles, I prefer to use minimal processing in mastering music, so that I am not inadvertently adding more noise and distortion during the process.


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STEP 3 - Processing

Finally, after the critical mastering steps mentioned above, I am now ready to actually get down to mastering your music! It has been quite a journey so far, but without that necessary pre-work, I would be working blindly. The processing stage is simply that - adding any necessary processing to accomplish the changes that I believe your mix needs to make it shine. 

I do not have a "Standard" processing chain, because every song is different, and the type and amount of processing varies depending on the client, the mix, and the musical genre as well. It all goes back to "what does the song need to achieve its full potential"?

My tools of the trade:

  • a very clean, highly configurable compressor
  • a very clean, highly configurable limiter
  • a very clean, highly configurable equalizer
  • a very clean, highly configurable digital audio workstation
  • a very clean, highly configurable sample rate converter

Are you seeing a theme here ;)? I tend to stay away from processors that "Add warmth" or "Add character". There can be exceptions to this, but in general, I prefer to choose tools that are relatively transparent, and have enough configurability to control exactly what they are doing to your mix. 

For more information:



STEP 4 - Finishing

After I have achieved the tonal, spatial and dynamic adjustments that I believe your mix needs, and have taken the necessary time to review them with you, I move on to the "finishing" stage. Finishing a master involves double checking its intrinsic loudness to ensure that it is appropriate for the song and the genre. I also take steps to ensure that the loudness is set in context with the other songs in your project. 

I also work with you at this stage to determine if fade ins or fade outs are needed, and we also discuss the gaps or amount of silence between the tracks. Many argue that this alone is an art form, and I do agree with that, but generally, I use the tempo and mood of the song to determine the intro and outro gaps, and length of any fade ins or fade outs.

Finally, I will add any required metadata to each file such as ISRCs, artist name, album name, etc.

Tools of the trade:

  • My ears
  • A high quality loudness meter that measures units in Loudness Units Full Scale (LUFS)
  • A DAW and sometimes a waveform editor
  • Metadata editing tools