📈Compressor Basics

Compression is a useful tool to ‘glue’ together multiple instruments, and to create a more even volume level on individual tracks. There are many compression algorithms that alter the sound in different ways, but the basic theory is that any sound louder than a set threshold is lowered at a set ratio (essentially how steeply the sound is lowered), creating fewer peaks of sound and lowering the overall dynamic range of audio.

To add compression to a track in Logic, open the Inspector by pressing “ I “, then click Audio FX > Dynamics > Compressor. You will see knobs for threshold, ratio, make-up gain, and a few others, as well as a meter that shows how much the sound is being compressed. To understand how compression works, try turning the threshold down and the ratio up. You should see the meter dip more and more into the negative numbers, and you will hear the dynamic range of the audio clip get smaller, giving it a kind of squashed sound. If you click the “Graph” button on the meter, it will show you what’s actually happening to the audio, with a window for how steeply the sound is being reduced, or attenuated, and a graph showing the the audio level after compression overlaid on the original audio waveform.

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Here, with a high ratio and low threshold, you can see that the loudest parts of the audio, also known as peaks, are lowered in volume dramatically. It is important to note that unless you are going for a specific sound, these settings are likely much more extreme than the type of compression used in most studio and production settings; however, like most aspects of music production, compression needs to be tailored to your specific application of it, and you will just need to work with until you develop an ear for it.