Audio FX Crash Course
So, the sound guy tells you to relax your gate cause you sound like a hog-trough. Rather than pick a knob and turn it all-the-way, the other way, take time to get to know your effects. Back in the day, audio effects were an art form in and of themselves. Today, they are digitally awesome but technical and complex. Here are some basic concepts:
EQ – Essentially, a volume knob for different frequencies. EQ is straight forward and arguably the most important effect. Want a boomier voice, kick-up 300 to 500 Hz; want a sizzling guitar, kick-up 6k to 8k (watch out for fret noise). A better use is to cut unwelcome frequencies.
Compressors – Ahh, what a marvel. Compressors take a signal and make the loud part softer. Think of it as, being able to hear the whispers inside a roaring jet engine. Subtle depth in your sound will be brought out. However, be wary of your noise floor. Limiters are a cousin of compressors; expanders function opposite. What does rock music and TV commercials have in common?… highly compressed sound. Using compressors in classical music will get you shunned.
Gates – A gate is used to control the flow of sound. If the total signal input is below a set threshold, it will close and stop the flow of sound output. Typically used to cut noise… you know, that amp crackle or breaths between vocal phrases. Lots-o-uses with percussion too. All around good way to clean up your sound.
Modulators – Broad category. Generally, anything that varies the frequency or amplitude of your sound… chorus, flanger, phaser, autotune (not to be confused with cartoon), overdrives, etc. These will fatten your sound.
Delay – Otherwise known as Echo, delay repeats a signal adding density. A great way to fill space and make some killer riffs sound out of this world. Play a note… get 32.
Reverb – In the real world, when a sound is made, it moves outward striking your ear directly while some of it bounces off walls, trees, cats, or whatever it encounters and reflects to your ear. Standing waves form around you and the source. Drop a rock in a pool of water… you see the initial splash and wave, then over time smaller waves. What’s important to understand is that the reflected waves are not the same signal as the original. Frequencies get absorbed and transmabogolated. This is the primary difference in how reverb and delay work. Want to sound larger than life?… give it some reverb (aka the talent knob).
Chain – The order you use effects has a dramatic influence on the sound ultimately produced. No absolute rights or wrongs; though, it’s good to have a limiter as the last step… fried speakers and components can make for a bad day. Oh, and running a parallel signal through side chains can make for some awesome enhancements.
Wet/dry – Wet is with effects (typically referring to reverb).
Gain – Most effects are not linear. So the signal’s input strength can have a huge impact on the effect of the effect’s output.
Level and mix ratio – Find your balance point between the raw and processed sound. In my humble opinion, subtlety is the key.