The process of applying upper harmonics introducing colour, adding brightness and grit to a sound.
Saturation is a term coined after discovering that an amplifier or piece of analog circuitry could be increased slightly above its suggested operating levels causing the unit to be overdriven.
This state of overdrive would colour the signal in a very harmonically pleasing way as it agitates upper harmonics instead of applying them like distortion does. This is where the term warmth is used to describe the colour saturation adds.
There are many reasons to reach for a distortion unit during sound design, mixing and even mastering. With this in mind, the usage of distortion varies from mild to extreme depending on the stage of production.
Sound Design
During the sound design stage, distortion is generally used aggressively to enhance, colour or completely change a sounds texture by increasing the frequency content. Filtering and subtractive EQ can then be used to control the sound once again and perhaps creating character with filtering techniques.
Here is where you can fully exercise the effects of distortion noting your favourite types in the process. Take time to learn the audible difference and effects of distortion (harsh) vs. saturation (warm).
Mixing
When mixing a project, distortion should be used much more lightly as you want to maintain the integrity of the sound itself.
Typically, applying distortion in the mixdown helps a track to appear in the upper end of the spectrum should there be a lack in clarity of the instrument.
After balance, panning, EQ and compression, some sounds may still have trouble in the mix. For example, an 808, a kick and a sub all occupy the bottom end of the spectrum. If more than one of these instruments are triggered at the same time, they may clash and sound muddy. Distortion increases frequency content allowing a sound to be represented higher in the frequency spectrum making it more audible to the human ear. This creates separation between the instruments.
Mastering
For the final mastering stage, distortion can be applied to warm the sound a little more and create loudness. As with all processors on the master channel, this should be minimally applied.
Tip: The “Soft Clip” feature found on the “Glue Compressor” and the “Saturator” will help with warmth.