The Art of Mastering Your Audio
Audio mastering is one of the basic post-production components of preparing professional music recordings such an album, radio or television commercial. It can be seen as the final touch to an audio recording that has already been successfully mixed as it is transferred to a data storage device called a master. This storage device then becomes the master of all future copies that are produced, usually for retail sales or radio station distribution. Masters can be stored in digital or analog formats, but digital has become the most popular choice today.
Audio mastering will add a cohesive feel to your album or compilation and ensure that the sound levels of the different songs or separate recordings are all similar with a smooth flow in volume from one track to the next. This is accomplished with compression, EQ, and gain so that your recording is equalized, balanced and enhanced. If is my professional opinion that to excel at mastering, one must have a keen ear with critical listening skills. And I believe it is more of an art rather than a simple technical skill you can easily pick up from basic training. I have found that some people just seem to have the gift of mastering while others will never get it no matter how hard they try.
Audio Mastering Equipment and Software
When preparing an audio master, we have great choices today on the necessary equipment and software. Equipment is becoming less expensive and the features and functions are making it much easier for mastering a substantially impressive master that will have that perfect presentation you are looking for. With the right computer-based equipment and software, you can master a recording that will put the professional “shine” on any track. As I stated earlier, critical listening is an extremely important factor in successful mastering. Fortunately, there are now mastering tools and software that make this somewhat less difficult.
Though everybody has their own tastes for the best mastering equipment, tools and software, I can assure you that there are some basic pieces of equipment you will most likely need if you want to be successful. This includes a compressor/limiter, a parametric equalizer, a harmonic enhancer, and a Digital Audio Workstation (DAW). In addition, make sure that your speaker monitors are accurate.
Some Audio Mastering Tips
Adjusting Sound Levels. When mastering your album, one of the main functions is to ensure that the different sound levels on the various tracks are similar. This is more complex then it sounds since similar does not mean making them all the same. If you simply make them all the same, you will have loud ballads and other volume problems problems. I have found it best to focus on the vocals (when present) for determining how well the sound levels match. In addition, my advice is to concentrate on the two tracks on either side of the one you are mastering.
Sometimes you may have to work with a mix where the tracks obviously need further work before an effective master will be made because of different recording environments on some of the tracks. If this is the case, I suggest using a parametric equalizer where you can focus on the bass ends for each track in order to equalize them with the next track. Some of my other tips for working with tracks include using a digital limiter to increase the loudness of a track if it’s already near its digital peak and operating a harmonic exciter when a track or a mix is lacking definition.
Using Compression. Though compression may not be the only aspect to mastering, I feel it is an extremely important part of the process. Compression of the audio range ensures that the audio does not exceed the decibel limits and sound to loud by compressing the audio peaks. Nevertheless, when compressing you are also boosting the frequencies on the soft parts of the track, resulting in a track that sounds flat with the right feel of the sound sometimes diminished or removed. This is why I advise that you should not just compress everything without taking other factors into consideration. Compression requires skill to get the sound just right and to make it workable with other factors like EQ, enhancement, and reverb. In addition, I have learned that a multiband compressor is handy in adjusting a mix’s spectral balance.
Handling Fadeouts, Gaps & Silence. It is best to choose a fadeout for an ending rather than mastering a silenced end, and I suggest that this fadeout should be started when the last music sound has decayed to around 5% of its maximum level and last for approximately one second after that. Though you can process fadeout endings while mixing, it is much better to use a computer editor while mastering since it can also perfect the fadeout to include everything including background noise. When it comes to determining the gap time between songs to enhance flow, I suggest a gap that is at least two seconds long but not more than four. The time of this gap should depend upon how the track ends with abrupt endings requiring more time, which can be felt while listening to the transition on your DAW.
The Master as a Finished Product. Once you think you have that perfect master, make sure you listen to it again while using headphones since this will allow you to find unwanted noises and sounds you may not have heard on the loudspeakers, including noises often discovered between tracks. Always write the crucial data on the master case such as sample rate, test tone levels, and track start times and lengths. Take my advice, always … and I mean always … make at least two masters. And then put them in different locations to make sure all your hard work is not lost or damaged.
-By John Redick