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How To Disappear Completely: My Year Of Working Without Corrective EQ

Creating an accurate translation of instruments for a larger experience, as though the PA isn’t there and the band is playing just for the fans.

A few years ago, I embarked on a quest to remove the last few bands of corrective parametric equalization from the input channels of my front of house mix for Umphreys McGee (UM). I spent two full years working out how to give up corrective EQ, and now I feel ready to explain how I did it.

It started with what I consider the core of sound for a rock band: kick drum, snare, and hi-hats. These three parts of the drum kit establish the core tempo and rhythm that the sound of the band builds from.

The kick drum should be ever present, solid but natural, with the lowest fundamental tone combined with plenty of beater contact. The snare drum should have a texture and complexity – an aggressive snap followed by a thick shell decay and a crispy wire rattle from the snares. The hi-hats are delicate and expressive.

The combination of a spring-loaded foot pedal and face-to-face mirror-image cymbals allows for a multitude of complex tonal options. Their decay envelope varies with pedal tension, from a short tick to a loose, splashy wash that works well in rock ‘n’ roll.

Add to this foundation a quartet of toms, rich and deep, with the clean snap of uncoated heads. The low richness of the skins is contrasted by a brassy chorus of cymbals, each with its own distinct voice.

The author’s input list.

I wanted my drums to sound like the drums on my favorite albums from the 1970s and 80s. I wanted “Aja” drums. I wanted “Tom Sawyer” drums, or my ultimate comparison, the drum tones Sylvia Massy got on “Undertow” – dynamic and impactful with rich overtones and beautiful decays.

I asked myself what was the difference between those drum sounds and my drum sounds. What qualities did I need to hone? The answer starts at the destination, not the source.

Accurate Representation

Music is enjoyed in our minds. The emotions we seek are created when our brains translate airborne pressure vibrations into synaptic excitation and then compare those to previous experience. Our brains do an extremely good job discerning the difference between sounds produced by the original source and sounds emanating from a reproduction of the original source.

I want the original sound of the band to be accurately represented in my mix. I do not want the audience to be distracted by the mix. It is a sound engineer’s goal to become invisible and facilitate an emotional connection between artist and audience, regardless of production level.

For UM, this means that the drum kit in my mix should sound exactly like drummer Kris Myers’ perfectly tuned Pearl Reference drum kit. I want the drums to sound like the listener is slightly above and in front of the drum kit, but at the volume I choose. To get this, I designed a way to combine multiple sources that would result in the drum mix I want.

Every mix engineer recalls the advice handed down from on high: It’s better to move the microphone than move the EQ knob. If the mic doesn’t sound good on the source, swap it for another that sounds better. But who has time to reposition the mic when soundcheck is in 20 minutes? Not to mention that most mic lockers are stocked to be homogeneous and interchangeable, with the same predictable options.

So what are we looking for when we move or swap the mics? Remember, I’m striving for truth in reproduction. Assuming the drummer (or tech) can tune a drum kit to sound great, then I should just have to make it louder, without changing the tone of any of the drums or cymbals. Choose a mic that has a flat frequency response, both on- and off-axis.

I knew that Earthworks mics could help me solve that problem. Known for ruler-flat response and extremely accurate translation of fast transients, the SR Series of cardioid and hypercardioid mics are a perfect choice for an accurate, truthful mix.

A comparison of microphone impulse responses.

One of the first mic changes I made was switching the drum overheads to Earthworks SR30s, and from a traditional separated pair of stands to an XY coincidental pair suspended directly over the snare drum mic. I was immediately impressed by how much more of the overheads I could use in my mix.

Soon I muted hi-hat, ride cymbal and snare bottom mics. Didn’t need them. The SR30s were providing an awesome stereo image of the top of the drum kit. Plenty of hi-hat and cymbal combined with the pop and snap of the snare and toms.

The “close” mics on the snare and toms were chosen to reinforce the rich low-mid overtones produced by the head and shells. I finally settled on a pair of Earthworks DP30/Cs on the rack toms and Audix D6s on the floor toms, with another DP30/C on the snare top and a Telefunken M80SH on the aux snare.

Earthworks DP30/C mics on the rack toms.

Addressing The Time Element

With the advent of digital consoles, many new features have entered the mix engineer’s toolbox. One of my favorites is input channel delay. If you’ve ever aligned multiple loudspeakers in a system, you realize the importance of time alignment between components. Without properly adjusted delay times, cancelations and summations create problems that can’t be solved with EQ. The same can be true for input sources.

Now that I was running my overheads at a high level in my mix (fader at +3dB, usually) I thought about delaying the snare and tom mics to allow the waveforms to time up with the waveforms picked up by the overheads.

I’ll support this with a little math.

Imagine the stick hitting the snare drum. The snare top mic is two inches away from the drum head and the sound wave takes 0.15 milliseconds (ms) to reach it. The overheads (XY) are an additional 44 inches away from the snare mic, taking 3.26ms more for the wave to reach the mics. By adding 3.26ms of delay to the snare top mic, I effectively align the waveforms in time, reducing the problems caused by phase cancellations and summations.

I tried this and liked the results so much that I built a spreadsheet to help me calculate the delay times needed for the tom and aux snare mics too. Not a huge change, but an incremental improvement towards the perfect drum kit sound. And to make sure I can get the same results every show, I use a heavy Atlas mic stand with positions marked in silver Sharpie.

Working The Kick

The kick drum was pretty straightforward with a few exceptions. I use the common dual mic technique, with a Shure BETA 91A attached to a small pillow inside the kick drum and an Earthworks Kickpad facing away from the beater head to shape the tone. This position better balances the tone of the shell and beater. I high-pass this mic at 160Hz, using it only for attack and shell tones.

For a long time I used an Audix D6, a favorite, in the front head hole for the bottom end. But I wanted a lower fundamental drum tone without resorting to EQ.

After a few experiments, I built my own Subkick-like transducer with a resonant frequency (Fs) of 38 Hz, dropping smoothly to around 80 Hz and gone by 160 Hz.

The Subkick-like transducer that helps in capturing a lower fundamental kick drum tone.

Combine that with the BETA 91A, which has 0.59 ms of delay to compensate for the distance between the transducers, and the result is a thick, solid tone that never gets swallowed by the bass guitar or Moog keyboards.

Dynamic Directions

The timbre and tone of the drum kit were starting to come into focus. But I couldn’t ignore dynamics.

One of the difficult parts of mixing a rock band is getting the dynamic range of the different parts of the band to sit in the mix with each other.

The drum kit is a very dynamic instrument, ranging from soft snare and cymbal rolls all the way up to bombastic cacophony, maybe 40 to 50 dB between quiet and loud. But the guitar amps may only range from 25 to 30 dB. Bass and keys even less.

Compressors help us match these up, but sometimes at the expense of tone and transient reproduction. It’s very easy to compress every channel and wrestle the drum kit into submission, but the old adage applies: “If your only tool is a hammer, every problem looks like a nail.”

I decided to trust the dynamic capabilities of our drummer and use no channel compression. I set up parallel subgroup compression to thicken the drum sounds and raise the RMS level, reducing overall dynamic range but allowing the excitement of uncompressed drum channels to pop in the mix.

This technique improved when I switched to the Earthworks mics. The transient response of the capsule accurately captures the very quickly changing waveform, impossible with the much heavier capsule used in dynamic mics like the Shure SM57.

Impulse Response

These approaches produced the improved drum sound I wanted. The mix became organic and dynamic. When Kris plays softer or louder, his dynamics and tones are accurately reproduced. Every stick impact and shell decay sounds faithful and sharp.

It’s relatively easy to twist and shape tones and levels to make a drum kit sound like almost anything. It’s much harder to remove any evidence that someone is behind the curtain.

I’m reminded of a U.S. Navy electronics course that I took, and specifically a class covering amplifier theory. The discussion was about a hypothetically perfect circuit described as “a wire with gain.” In other words, a device designed to pass a signal with no loss, addition or distortion – a signal that does not lose any integrity when amplified.

That’s how I think about my drum mix now: it should be just like standing in front of the kit, at whatever volume I desire. The accurate translation of a small sound to a large experience, like the PA isn’t there and the band is playing just for the fans.

Of course, a band is more than just a drum kit, and I had to make this approach work for every other instrument in the mix. Up next: more about manipulating electronics to allow thousands of people to share in the musical conversation being held onstage by six musical geniuses. Stay tuned for the marriage of drum and bass.

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