A compressor is not needed during audio mastering when the audio being mastered is already well-balanced and does not need further dynamic range compression or when the desired final result is a natural, unprocessed sound. Additionally, if the audio is intended to be used in a context where loudness normalization is applied, such as streaming services, the use of a compressor may not be necessary.
A skilled audio engineer or mastering engineer can determine whether an audio file needs compression during mastering by listening to it and analyzing its dynamic range, perceived loudness, and overall balance. They may also use tools such as a dynamic range meter or a spectrogram to analyze the audio’s dynamic range and frequencies. It’s also important to consider the intended use and final format of the audio, as well as the desired aesthetic, before deciding whether or not to use compression.
A dynamic range meter is a tool that can be used to measure the difference in volume between the quietest and loudest parts of an audio recording. The measurement is usually expressed in decibels (dB).
When using a dynamic range meter to determine if audio needs compression, the audio engineer will typically listen to the audio and visually monitor the dynamic range meter to see the difference between the loudest and quietest parts of the audio. If the dynamic range is too wide and some parts of the audio are too quiet or too loud, compression may be needed to bring the audio into a more balanced range.
The engineer will adjust the threshold, ratio, attack, and release of the compressor to bring the loudest part of the audio to a desired level without over-compressing the audio and making it sound too “squashed” or “pumping.”
The “best” dynamic range level after audio mastering can vary depending on the genre of music, the intended listening environment, and personal preference of the mastering engineer.
Dynamic range is the difference in decibels between the loudest and quietest parts of a recording. A higher dynamic range means that the quiet parts of the recording are quieter and the loud parts are louder, while a lower dynamic range means that the difference between the quiet and loud parts is smaller.
Generally, a dynamic range of around 10-14 dB is a good target for most types of music. However, some genres of music, such as Classical and Jazz, may require a higher dynamic range to better showcase the nuances and details of the performances. On the other hand, some genres such as electronic music and pop may have a lower dynamic range.
It is also important to note that loudness normalization algorithms used by streaming services and other platforms will tend to reduce the dynamic range of a track to make them more consistent in level with other tracks. This means that mastering engineers may have to aim for a lower dynamic range to achieve a target loudness for streaming.
Ultimately, the best dynamic range level for a particular track is one that sounds good and achieves the desired balance between loudness and dynamic range.