there's a reason gates are a mainstay in nearly every mixing console but they seem to have lost some favor in the age of digital production. but gates are no less valuable now then they've ever been. whether you want to quickly and automatically clean up a recording or use them as a creative effect, the gate is an important tool in your dynamic control arsenal.
if you enjoy this article, be sure to check out my article on the basics of compression.
let's have a look at what the settings of the gate do and think about ways we can use them to better our production:
here's a gate with the threshold down low enough that some of the signal passes below and some passes above. nothing is happening to the aptitude, however, because we've told our gate not to do anything to signal that crosses the threshold. let's change that:
we've set the floor to infinity. this tells the gate to remove all amplitude from a signal when it crosses the threshold into the "land of the red" (lotr™). notice how outside the lotr™ the signal is unaffected - the gate only works inside the threshold. the lotr™ is the jurisdiction of the effect and it has absolute power within its borders.
that doesn't mean it always needs to exercise the infinity of its power, however. here we have the gate with a higher threshold but lower floor. the interaction of these two are the most essential components of the processor. the lower the floor, the less drastic the effect and thus the more transparent it will be look how the gate turns on and off instantaneously. this is rarely desirable behavior as it can be very jarring and unnatural. let's see how to ease that a little bit and make the effect a little more useful:
I've added a bit of attack. you can think of the attack less like a delay of effect and more like the amount of time it takes for the gate to fully "catch up" to where it "ought" to be. compare this signal to that of the one above and notice the differences - for starters, the gain reduction is more pronounced; we've raised the floor slightly. but more importantly look how it takes a bit of time for the amplitude to "get on track" in this new example. also notice that attack only affects the turning on of the gate - when the amplitude crosses back out of the lotr™ it is still instantaneous.
I've modulated the threshold in this example to better illustrate the use of "hold", which sets the minimum amount of time the gate must remain open. the timer starts as soon as the signal leaves the lotr™. see how in the first peak the amplitude follows it's unprocessed path even as it crosses into the threshold? that's because the gate needs to wait 40 (that's 4 ticks in our scale) before it's allowed to act. in contrast, the second peak enters the lotr™ after this appointed time and hence is acted upon immediately.
hold is really useful if you have really sporadic audio. imagine this scenario - you've recorded an interview and the mic was really noisy. so you have white noise throughout the tape that you want removed and you're going with the gate instead of taking it out by hand - good choice. but human speech naturally fluctuates in amplitude and you don't want the gate closing rapidly in between words - it will sound like your audio is glitching. raising hold to an appropriate time will keep the amplitude consistent between words but still allow for the gate to close during longer passages between sentences.
release is another handy feature to make your gating more natural. just like attack, release is a "catching up" time but on the exit from the lotr™. the gate is asking "how long do you want it to take me to gather up all my things after you've booted me from your house?". it is a gradation of the effect post-threshold crossing. like hold, it makes the effect of gating less harsh. but unlike hold, the timer starts when the signal leaves the lotr™ and it is not binary - again, think gradation.
so what's return, I hear you asking? return separates the threshold of entry and the threshold of exit. that is, the gate will cease to process your signal once it leaves the lotr™ and will not activate again until the amplitude drops below the threshold less the return amount.
ok, I promise this isn't as hard to understand as it looks. what we've introduced is a sidechain. this simply means the gate will process a signal that is different than the one it is affecting. so our gate is set to reduce the gain by 30 of any signal below -20. watch the green line - it will be reduced by 30 when and only when the blue line enters the lotr™ regardless of what it's original amplitude (yellow line) is doing. take note there is return on the gate as well, so the clampdown doesn't happen until blue crosses the -30 (-20-10).
that's it! remember you can find all of my production tips here and follow the socials to never miss a new tip//