Gates are the Rodney Dangerfields of the processing world. They “don’t get no respect.” They were routinely used back in the analog days to remove tape noise from tracks coming from tape. When the audio world went digital, their fate didn’t improve — if anything, it got worse. Even if you are tracking real drums, it doesn’t make sense to call up a processor just to get rid of background noise. Why instantiate a gate plug-in when you could just use the “Strip Silence” function and not tie up real-time processing power? This attitude explains why there are literally hundreds of compressor plug-ins but only a handful of gates out there. But I’m here to tell you that there are still some very cool things you can do with gates in the digital world.
Sidechains and Keys
Dynamics processors of all stripes make their decisions on whether they pass, mute, or squish the audio based on the signal passing through them. The key (pun intended) to making them a creative tool in a DAW is sidechaining. This is the process where we let different audio (from a separate track) control the way the dynamics processor reacts rather than the audio that’s running through it, the track that the plug-in is instantiated on. Various DAWs implement this process in different ways, so I will give you some examples, but you might have to look at your manual to apply this process on your DAW/plug-in of choice.
Snare Repair
“My snare has no snap.” This is a problem we can fix with a gate. First, create a new audio track and put a white noise loop on this track. Within Pro Tools, create a send called “Drum bus” on the snare track. Put the gate on the track with the white noise, and select the drum bus as the key input for it. In the example shown in figure 1, I have the gate set so it opens for a very short period when the actual snare hits. I have also placed a plug-in to add some distortion after the gate for a touch more color. Just mix the white noise in to taste to add some high-frequency content to the snare.
Bass in Place
The bass on this track just needs something to make it a little less run of the mill. I went way too crazy and used Melodyne to create a MIDI version of this bass track, and I am using it to drive a bass sound an octave lower from Rob Papen SubBoomBass. Unfortunately, the output was a bit floppy, so I wanted to gate it based on the original track with Softube Valley People Dyna-mite to tighten it all up. PreSonus Studio One manages its key functionality as you create a send on the track to go to the track you have the gate actually effecting. Begin by adding a gate on the new bass track you have created and engage the EXT. S/C button (outlined in red on fig. 2) on its GUI. Then create a send on the original bass track, but select Sidechains in this menu, and you should see the gate plug-in you just created in the menu. Select this, and you are now using the audio in your original bass track to open and close the gate on the new MIDI instrument version of the bass you have created. Magic!
Pulsing Pads
If you listen to much dance music, you are used to hearing pads that pulse perfectly to the beat of the drums. If you thought they had a keyboard player with great rhythm, I am sorry to be the one to disappoint you. This effect is almost always created with a gate.
Ableton Live makes this effect easy if you have one of their native plug-ins that supports sidechaining — and kind of challenging if you want to use a third-party plug-in with sidechain capability.
In this instance (fig. 3), I have a pad from Spectrasonic Omnisphere on Track 1 that I want to pulse along with the drum loop I have on Track 2. Place a gate, such as the Dyna-mite gate, on the Virtual Instrument track (Track 1 in the screenshot), right after the instrument plug-in, and engage the Sidechain control (EXT. S/C) on the plug-in (outlined in red). Then create a return track in Live and set its Audio From menu to the audio track you want to key the gate. Click the Monitor In button on this channel and route the Audio To menu to the Virtual Instrument track you are using. The Sidechain option will then show up. Turn the threshold down to the point where it starts to open with the beat of the drum loop, and then the pad on Track 1 will begin pulsing to the same rhythm as the loop. You sound like an expert already!
If you want to know more about gating, or sidechaining, or what plug-ins work best for this, give your Sweetwater Sales Engineer a call at (800) 222-4700.