SOLID MIX SERIES

Producers use a combination of compressor plus gate/expander to sculpt sound. This is known as dynamics processing.

A compressor is basically an automatic volume control, making the quiet parts of a track louder and reducing over-loud peaks for a more consistent, even sound. Find out more...

An expander reduces the level of any sound below a specified threshold — if a sound isn't loud enough to reach the threshold, the expander makes it even quieter. Technically, it's expanding the dynamic range downwards.

A gate is the extreme form of the expander: it simply silences sound below the threshold. When the gate is closed, quiet sounds below the threshold — the ones that got recorded by accident — can't pass. When the sound is loud enough, the gate opens and the signal can pass through.

Gates and expanders are essential for scraping off background noise such as the sound of your computer, amplifier hum or bleed from the headphones. On multiple tracks, even the quietest background noise can stack up and cause problems in a mix, so use a gate whenever you're mixing vocals or recorded instruments.

Unless you're recording in a premium studio, your recordings will have some background noise. Find a section of the track without singing, and listen for the pops and mouth sounds. Gross. Audition that section, and slowly raise the threshold of the gate until you can't hear the noise. Check to make sure that you're not cutting bits off the vocal performance, and you're done.

If a snare is recorded with two microphones (one for the top, one for bottom), use this trick to make the snare really snap: Invert the phase on the bottom mic track, then add a gate effect with the top mic track as sidechain input.

For interesting rhythmic effects, use a gate on a pad sound, with your drum track as sidechain input. Listen to this effect in the ‘Gated Pad Demo’ above.