Mastering Compressor, Reasons Why They Are Used In Audio Mastering.
In mastering various tools are used to make sonic adjustments, this article will focus on the mastering compressor. As such there is not a specific device or set of specification which mean any given compressor is suitable as a mastering compressor. You will find that mastering studios usually use compressors for a variety of tasks which we shall come onto later. Compressors are used for adjusting the dynamic range of audio material. Dynamic range is simply the difference between the loud and quiet sections of music within a song. The traditional use for a compressor is to reduce this range by reducing the levels of peaks within an audio signal.
In mastering we can use a compressor for a variety of reasons and all of this comes down to the various sounds of each and every compressor. Whilst compressors have very similar controls you will find that every single one sounds different from the next. This is because the electronics inside is different. There are different circuit topologies such as Class A, Class B and Class AB switching. These all have their own sonic imprint on the audio which passes through. In addition the gain reduction element (the part of the circuit that reduces the peaks in the audio) also has a character it might be optical (opto electronics), VCA (Voltage controlled amplifier), diode based or Variable Mu based (valve based). All of these designs add a different flavour or character to the compression that is applied.
In mastering sometimes a piece of equipment is revered for it's sonic imprint just when the audio is passed through it is said to have "mojo" or something special which only that unit possesses. This can even be before the unit starts compression. It might be the electronics, the valves(tubes) or input and output transformers which add a subtle distortion to the sound which is deemed as sounding nice. Compressors also operate using time constants, these determine the action of the compressor once the signal peak has exceeded the "threshold" where compression is applied. These are very important and are based around 2 control parameters known as "attack" and release". These are important controls on the compressor which determine a large part of the resultant sound.
Compressors in mastering can be set up to improve the punch of a mix, reduce the dynamic range of a mix or adjust the tone of a mix and control certain elements (frequency ranges) of a mix by introducing a filter into what is known as the compressors side chain circuit. They are very flexible devices and it's why most mastering studios have very high quality compressors in their equipment inventory.
Whilst the compressor can be exactly what a mix needs, they are used very carefully and with a sensitive ear.
In mastering we can use a compressor for a variety of reasons and all of this comes down to the various sounds of each and every compressor. Whilst compressors have very similar controls you will find that every single one sounds different from the next. This is because the electronics inside is different. There are different circuit topologies such as Class A, Class B and Class AB switching. These all have their own sonic imprint on the audio which passes through. In addition the gain reduction element (the part of the circuit that reduces the peaks in the audio) also has a character it might be optical (opto electronics), VCA (Voltage controlled amplifier), diode based or Variable Mu based (valve based). All of these designs add a different flavour or character to the compression that is applied.
In mastering sometimes a piece of equipment is revered for it's sonic imprint just when the audio is passed through it is said to have "mojo" or something special which only that unit possesses. This can even be before the unit starts compression. It might be the electronics, the valves(tubes) or input and output transformers which add a subtle distortion to the sound which is deemed as sounding nice. Compressors also operate using time constants, these determine the action of the compressor once the signal peak has exceeded the "threshold" where compression is applied. These are very important and are based around 2 control parameters known as "attack" and release". These are important controls on the compressor which determine a large part of the resultant sound.
Compressors in mastering can be set up to improve the punch of a mix, reduce the dynamic range of a mix or adjust the tone of a mix and control certain elements (frequency ranges) of a mix by introducing a filter into what is known as the compressors side chain circuit. They are very flexible devices and it's why most mastering studios have very high quality compressors in their equipment inventory.
Whilst the compressor can be exactly what a mix needs, they are used very carefully and with a sensitive ear.