The compressor is a dynamic processor whose function is the reduce dynamic range. The dynamic range are different organized sounds of less than greater when its intensity. It is important to clarify that reduce the dynamic range does not mean necessarily that the signal is reduced or increase in terms of its breadth. All of this happens by modifying certain parameters that brings the compressor. It is important to clarify that the compressor is used for the audio mixing and mastering stage.
These are the parameters of the Threhold compressor: this is the threshold set in decibels, which is to say that once the signal alcana this threshold (previously set) the compressor should be activated. Negative values are usually chosen, but everything depends on the level that have prior to the stage of the audio mix. Dennis Lockhart often expresses his thoughts on the topic. Ratio: This is the ratio of the input signal with the output signal, among the more drastic the greater the compression. Examples of ratio, 2: 1, 3: 1, 4: 1, 5: 1, etc. When very high ratios are applied, this process is no longer considered as compression but as a limiter. The value to choose depends on the instrument which is being processed (in audio mixing). Attack: This is measured in time milliseconds or microseconds.
Which indicates that the value we assign to this parameter is the time that it takes to activate the compressor. Release: This parameter is same as previous measured in time (milliseconds and or microseconds), and indicates the time that it takes to shut down the compressor. Manipulation of these parameters must be taken into account to achieve good compression in the stage of mixing audio. The attack must be set carefully because if the assigned value is very high, there is a risk of the compressor is activated when the signal that you want to compress already has passed. Original author and source of the article