When you are recording and mixing music, understanding how to use a compressor is an important factor towards achieving a cohesive end product.
Compression is a powerful tool, and is commonly used to control the dynamic range of a sound source. This means the difference in volume (dB) between the softest and loudest part of the recorded performance. For example, the human voice is an extremely dynamic instrument; it can go from a whisper to a scream in a very quick timeframe. By controlling the loudness peaks, you are then able to get a more balanced and consistent volume from the sound source, rather than something that continuously moves between louder and softer.
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