What is Audio Mastering (Digital Mastering)?
Audio Mastering, or Digital Mastering as some call it is the preparation of your final mix onto the medium that you will use for future duplications.
In the past Mastering was the process of transferring your music from magnetic tapes, used in the recording studio, to a phonograph lathe for the manufacture of vinyl records. This was an extremely skilful process that happened in real time, with any mistakes that the engineer made appearing in the final master disc. However with the advent of the compact disc and the digital revolution the lathe was replaced with computer workstations allowing for sophisticated manipulation and an ability to get it right before committing to the final product.
The recent developments in digital technology has fuelled a massive growth in music that is "home-grown" as apposed to large expensive studios with highly trained engineers and staff. This has lead to a flood of basement and bedroom studios springing up worldwide. While these studios are a great environment for creating music, they do not usually have the same acoustic treatments and architecture that the high-end production houses have. This leads to musically brilliant and varied recordings but often sonically unbalanced mixes. When a mix is unbalanced for example a vocal too quiet, the mastering engineer has to compromise, while he can boost the vocal level by isolating the frequency where it sits in the mix, any other component e.g. guitar that shares the same frequency will also be boosted.
This is where the skill and expertise of the mastering engineer comes into play. With considerable experience the enhancements made to the track e.g. loudness and punch, will be maximised while the apparent changes to the mix minimized. This area of potential compromise requires a trained ear and in-depth technical knowledge to successfully avoid. Done poorly the mastered tracks can often sound less like a "record" a more like a "demo".
The process will vary according to the specific demands of the tracks to be mastered. The typical steps of mastering are:
1. Audio edited or arranged as it finally appear.
2. Eliminate undesirable artefacts (hum and hiss).
3. Make any audio corrections: Level, Tonal Balance and Dynamic Range.
4. Transfer the audio to the final format.
Example of a typical mastering session:
1. Listen to the source audio and identify problems.
2. Application of noise reduction techniques.
3. Set the highest peaks in track volume not exceeding 0dbfs or "Normalize"
4. Application of Compressor/s to control the peaks but expand the softer sections.
5. Application of Equalization (E.Q.) to affect the tonal range.
6. Application of Dynamics Processor (Selectable Bandwidth Compressor / Multi Band Compressor) to control specific or problematic frequencies.
7. Transfer or "Put Down" the final master.
Mastering for broadcast is slightly different as the bandwidth has to be reduced. e.g. application of a high pass filter set low at 80hz with -18db / octave and a low pass filter set high at 12khz with - 10db / octave to reduce the frequency range.
It would be worth noting that this is not a rigid procedure. The master is related to the original source material via the needs of the musician, producer and the client. In short mastering is a "Delicate balance of art and technology".
At NextLevel Audio we offer professional, affordable Audio/Digital Mastering services. Click Here to upload your tracks for free, no obligation mastering of your tracks.