Drums, Limiters, Gates, Hugh, Pete and Phil, etc.

Drum bus compressors have become a big deal. What follows are some ideas, some things to try, and some history to know about drum bus compression.
June 15, 2020
Psc In Heaven

Drums, Limiters, Gates, Hugh, Pete and Phil, etc.

Drum bus compression has really become a "thing." Hit an online forum like Gearslutz and there's tens of thousands of posts and just as many opinions on which hardware or plugin to use, what settings, VCA vs. FET, SSL or API and on and on and on. People drop thousands on a vintage ADR Compex, and it sits idle in the rack until mixdown, and then it does the only thing it will do on the record: squash the drum bus. It's ridiculous.

But it's also really cool. Ridiculous and yet really cool: that's audio engineering. $18k on a vocal mic, and then turn the track into Cheez-wiz by running it through Auto Tune so it sounds like someone wired up a baby duck to a sequencer? Excellent!

I love this stuff so much. So silly. So cool. Sigh.

Anyway.

Get the drum bus compression right and the kit kicks ass. Do it badly, and the whole record sounds like ass. The following is a combination of history, opinion, things to listen to, some production ideas and WTF. Here we go.

My Virgin Bus Compression Experience

Of course, if you solo'd out the 1176's channel it sounded just awful. Like your mom is Lars Ulrich in drag and yelling at you.

First time I saw someone bus compress the drums was in the mid-eighties in NYC at some studio (Sorcerer?). I was a dumb kid at the time who wanted to be helpful but mainly was the fastest mic cable coiler in the world. The engineer had a mix going. He assigned the kick, snare and the overheads to a bus, patched that into a lone UREI 1176 that looked like it spent a long weekend with Madonna , and then routed that back into the console in mono, panned down the center. First time I ever saw Parallel Compression. Then he pressed down all four ratio buttons of the 1176 (first time I saw that, too), cranked up the input, pinning the gain reduction meter, and brought it up in the mix slowly until suddenly the drums were THERE, you know? BOOM! Instant awesome.

Of course, if you solo'd out the 1176's channel it sounded just awful. Like your mom is Lars Ulrich in drag and yelling at you. Whatever. But in the mix, it was sublime.

I don’t remember the song or the group, but the sound was very similar to Don’t Fear the Reaper, and I suspect that there’s an 1176 with drums down the center of this recording (in addition to more cowbell). I had a chat with the drummer, Albert Bouchard, about this years ago, and he said some things to indicate this was the case.  If you listen the drums are strangely mono, and especially in the middle break, when he plays a fast hi-hat figure, it sounds like the pumping of an 1176 to me.

So there's a thing to try

Squash the crap out of the drums, bring them back in mono up the center of the mix.

So, bus your drums, or a few of them, to an open bus, strap a compressor across it, and then bring it back into the mic in mono panned down the center (or back in stereo if you wish, that’s fine, too.

This is parallel compressing, which is when you run an effected signal at the same time as an un-effected signal. In the old days it would use up faders and channels. Nowadays, faders and channels are basically unlimited, so parallel processing of all sorts is rampant. It gives you a lot of control and expression. For instance, you can automate the parallel track, and just bring it up during drum fills, during a break, etc. You can crush the drums, eq them weirdly, and then bring them up in the mix just make a moment more interesting, all sorts of fun. Works great on vocals and solo instruments.... really, just about anything.

What is with the 70's???

A mermaid gasping for air after you accidentally harpooned her sort of thing going on.

The 70's either have the greatest drum sounds or the absolute worst, depending on your viewpoint and whether or not you like your drums sounds huge and roomy or dull and reminiscent of someone hitting a couch with a broom.

The '70's dead room thing is all over records from California in the 1970's. There are some great songs, but the drums are noise gated and recorded in a dead little drum booth. And while the song is amazing, the drums on Life's Been Good...?

Dead drums are probably more about the advent of noise gates as a viable technology in the early 70’s than anything else. The industry tends to adopt a trend, milk the hell out of it, and then abandon it for whatever cool thing comes next.

One band never succumbed to the whole dry drum thing, and that's Led Zeppelin. Those guys always recorded drums in live rooms with minimal mics, and those sounds have stood the test of time. The archtypal track is When The Levee Breaks - good lord, what a drum sound!

Early Zep records were recorded in houses and other non-studio situations. The console used was typically a Helios, which were amazing, mainly custom made. Only 50 were ever built. When the Levee Breaks is an 8 track recording, so the drum "bus" compression really a drum track compression: stereo drums squashed through a Helios board compressor. Or not! Helios compressors were made by ADR, so what is happening there is bus compression through an ADR Compex, which, like the 1176, uses an FET. Seeing a pattern?

The Compex is a one trick pony, but it is a great trick. There is no real way to get a Compex to ever sound unnoticeable. Even with the most minimal of settings it imparts a lot of character. Picture a chef who has basically one recipe, which is take whatever it is, add bacon and fry it. Yes, delicious, but for soup? Salad? Ice cream? That's a Compex.

So there's a thing to try

Bus your drum tracks and feed them through our Pawn Shop Comp. Set the RATIO at at least 10:1, the ATTACK to around 7ms, the RELEASE to about 80ms, click AUTO for make-up gain, and then turn the threshold down until the meter shows at least 5dB of gain reduction on a steady basis. Instant Compex. And much cheaper than $2k AND you can use the Pawn Shop Comp on just about anything.

Now, so far, all of these compressors is based on a FET. The Compex, the 1176, the Pawn Shop Comp, the Talkback Limiter - all use a FET style of compression. SO... what’s special about a FET compressor?

FET (FET stands for Field Effect Transistor) compressors have a very distinctive vibe, especially on drums. FET’s were one of the first ways engineers made a solid state compressor (as opposed to using tubes), and the basic circuit design and sound has been the same for decades. These suckers are punchy and with fast material and quick release settings, they have a "mermaid gasping for air after you accidentally harpooned her" sort of thing going on. Quirky, but usually awesome sounding on drums.

Peter, Hugh, Phil, the 80's and MAKE IT GO AWAY

The things the two tracks had in common was engineer Hugh Padgham, and his accidental invention, gated reverb.

I was 16 in 1980. A friend had just bought the latest Peter Gabriel record, which was called, Peter Gabriel. His first four albums were all called Peter Gabriel. The 1980 record is nicknamed "Melt" because the cover image is a picture of the man himself with his face half melted.

The first song on the album is a real toe tapper called "Intruder," and sing along kids! It's about a home invasion from the point of view of the invader.

The thing about Intruder, though, is the drums. They had a quality and sound we hadn't heard before. Electronic yet acoustic. Huge but yet squashed and contained. We had no idea what was going on.

And then Peter's former Genesis bandmate Phil Collins released a track called In the Air, that had one of the most iconic drum sounds ever heard... and it sounded a lot like that Invader song.

The things the two tracks had in common was engineer Hugh Padgham, and his accidental invention, gated reverb.

Big commercial studios typically had (or still have) a microphone or two hanging from the ceiling so that the staff in the control room can hear activity in the studio; musicians can simply speak or shout a bit to be heard by the engineer, etc. Solid State Logic added a dedicated listen mic system to their SL4000 E console, and the circuit included a limiter. It had two purposes: 1) Amplify the quietest signals in the room so even someone speaking in a normal voice in the studio could be easily heard in the control room, and 2) Protect the control room speakers and the engineer's ears from loud noises or bangs or enraged lead singers by severely limiting the signal.

The SSL listen mic limiter had a fixed ratio of 100:1, almost instantaneous attack and release, and huge amounts of gain. It was buried down deep and hard wired into the console and wasn't designed to be adjusted. And... it used FETs... is the pattern clear now?

Engineer Hugh Padgham put a noise gate across its output, ostensibly because he didn't want to hear any quiet background noise that can be distracting during a session.

So, Peter and Hugh (and Phil Collins on the drums) are working on Intruder, and Phil is bashing around the kit, and it sounds amazing over the listen mic. Because the talkback limiter was applying huge amounts of gain, which amplified the sound of the room, then crushed the hell out of it, and then the noise gate chopped off the signal abruptly, eliminating the natural tail of the decay of the room.

Hugh Padgham figured out the routing to get the signal to tape, and the sound of the 80's was born, big hair and all. After Phil Collins' In the Air Tonight became a megahit, the gated reverb sound spread everywhere. Michel Jackson, Prince, Madonna, INXS, The Cure, New Order and on and on... it was everywhere. There was no escaping that big ass dumb drum sound.

I was never a huge fan of it, so I was glad it kind of died out. But like many thing, it is back and has become increasingly common again. It is being used with more subtlety (and perhaps taste) then it was during the '80's, but the '80's were never about subtlety. The 1975 have been pilfering a lot of sounds and ideas, including some gated reverb.

So there's a thing to try

Put the Korneff Audio Talkback Limiter across a snare or a kick track and put a noise gate after it. On the Talkback Limiter, turn LISTEN MIC all the way over to the right and have WET/DRY all the way over to the right as well. On the noise gate, set the gain reduction as high as possible, like -100dB, and the hysteresis to around -3dB. Set the threshold such that the gate clicks open for just the kick or snare hit and doesn't trigger on any leakage. Set the attack of the gate as fast as possible, the release to around 100ms, and then adjust the hold for how long you want to hear the effect. Tweek the Talkback Limiter to get distortion or more or less compression, and adjust the gate, especially HOLD, for the effect's duration. You can get a more subtle effect by setting the gate's gain reduction to something around -20dB and backing off on the Talkback Limiter's WET/DRY control.

Gating a drum bus or gating room mics on a kit is a little more involved, and this is where bringing the gated effect back in parallel might be useful.

Send the tracks you want to effect to a stereo bus, and then put the Talkback Limiter and a noise gate on the bus inserts. You'll rough out your sound as described above, but then you'll probably need to use the sidechain filtering of the noise gate to keep the effect from chattering on and off on high hats or whatever else might trigger it. I general set the gates’ filtering to bandpass, and then set the high cutoff to around 1kHz and the lows to around 100Hz. You can control the overall amount of the gated reverb effect in the mix by bringing up the bus's level in parallel to the rest of the drum mix.

It might take a bit of experimenting to the the sound you're looking for, especially if you're compressing and gating the room tracks and there's high hat leakage. Another trick to clean things up is to key the noise gate off of the kick, snare and tom tracks, such that the gates opens up and lets the crushed room sound through just for those instruments. Describing that sort of set up is long and detailed, and this whole column is dragging on at this point.

Of course, just running the room tracks through the Talkback Limiter instantly gets you a sound that is a lot like gated reverb. Increase the gain and you can pretty much match the drum sounds on Radiohead's The Bends album, which are simply fabulous: huge, trashy and percussive.

It is really worth your time to get your drum bus compressor situation suss'd out, whether you use plugins - my fave is the Pawn Shop Comp for this but our Talkback Limiter is great when I want more raunch out of things, or hardware - I use a pair of Compex2’s (like a Compex but with VCA’s instead of FET’s) when drum bus compressing in the material world. Dan Korneff, of course, favors the Pawn Shop Comp and the Talkback Limiter (he did build them for his own use originally) and he favors the original stereo Compex (which has FETs's) when he wants hardware compression.

Dedicated hardware bus compressors might be beyond your budget, and that’s fine. They might not be all that cost effective. My Compex2’s basically sit in the rack until mix time, forlorn and lonely, like the boyfriend of the mermaid we harpooned earlier. Every now and again I try them on something, like a guitar, and they promptly strangle it. Sigh. Back to a tube thing.

Well, that is it for today, kiddos. Some history, some ideas, some bizarre analogies, a little WTF.

Until next time, make great music, make great records.

Luke D. 6/17 in the year of the plague