Drum Clinic pt. 1: Kick Drum Viagra

PLEASE NOTE: This article has been archived. It first appeared on ProRec.com in August 2007, contributed by then Editor-in-Chief Rip Rowan. We will not be making any updates to the article. Please visit the home page for our latest content. Thank you!

Getting a good kick drum sound often seems more like luck than skill. It’s all too common: a small, thuddy kick. Poor attack. No tone, or bad tone. The kick doesn’t cut through… or, if it does, it sounds so bad, you wish it didn’t.

Fortunately, there’s new help for your limp, flaccid kick drum. It’s not a perfect science, and will require work and practice on your part. But with some effort and skill, you can get a bigger, thicker, more masculine kick drum sound. A sound you’ll be proud of.  A sound you’ll want to show all your friends.

OK, scratch that last part.  That was wierd.

Goals

It’s important to know what kind of sound you’re going for. There are a lot of “good” kick drum sounds, but of course they won’t all sound good in your particular mix. Take the popular metal kick sound from early Metallica or Korn CDs: tons of clicky attack, a really deep, thuddy fundamental, and no sustain or ambience. In most mixes, a drum sound like this would be utter and complete crap. But in a metal mix, it’s almost essential. Besides being a part of the “signature sound” of metal, there are reasons why this sound works in a metal mix:

  • the bright, in your face attack helps cut through the thicket of ultradistorted guitars
  • the muddy, thick guitars and bass practically demands that the kick tone must be lower and deeper, requiring a deep fundamental tuning
  • the drummer’s use of 16th note kicks requires a very fast, tight drum sound to articulate the performance

Conversely, in a jazz or natural sounding pop mix, a kick drum that has a natural sound is preferred:

  • the mix is dynamic, leaving room for a less exaggerated kick attack
  • the lighter guitars aren’t covering up the low-mids / upper bass regions, allowing a more “woofy” kick sound
  • there are no 16th note kicks, allowing a little more tone, sustain, and ambience in the sound

Or, for example, if you’re doing a classic punk mix, you don’t want lots of deep bass. Part of the energy of this sound is having a “snappy” bass sound with both the bass guitar and the kick. The kick should be punchy, but not thuddy.

So it’s really important to have a clear idea of where the drum sound needs to be.

A lot of drummers just don’t get this. The drummer is heavily influenced by, say, Tommy Lee, and has this monster kick drum that sounds bigger than life, but he’s playing with a alterna-pop band that covers the Lemonheads. Newsflash: his kick drum sound may be cool, but for this recording, it’s all wrong. If you record his kit, and try to get a mix, you’ll never succeed. So it’s absolutely important that you are able to work with the drum sound to get the intended tone from the drum. Garbage in, garbage out.

I’m a drummer, and I’ve spent over two decades recording drum kits. I’ve made a ton of mistakes. Over the years, I’ve learned a critical lesson: really good engineers are excellent drum technicians. For this reason, I have a kit set up in my studio that I’m intimately familiar with. I know this kit like the back of my hand, and I strongly advise drummers to use my kit.

The last time a drummer convinced me to use his kit, here’s what happened. We loaded in his kit and set it up. I pulled all the drum mics off of my kit and miked up his kit. I started getting tones and recording some test tracks so he could hear them.

This drummer is a good player. He has a jazz / drum line background, so his drum tastes are what I call “drummerly”: a ringy, high-pitched snare; an undamped, boomy kick with a front head; highly-pitched, undamped toms; and really bright cymbals. This makes for a kit that sounds really good all by itself in the room… but the dominant ringy snare and tom overtones, the glass-cutting cymbals, and the boomy kick are completely unmanageable in a pop mix.

And so it went. We started by working on the snare, tuning it down, adding a ring-off, and, finally, replacing it with my snare. Then the kick: pulled the front head, added a pillow, replaced with my kick. On and on this went until finally, we had replaced all of his drums with my drums. The entire process took about three hours and was a complete waste of his time and money.

I’ve played a lot of kits with a front head, both ported and unported.  A well-tuned kick drum with the right unported front head can sound absolutely monster in the right room.  I played a kick like this for several years.  It was especially cool in a long, semi-live room – since it was so loud and moved so much air, it needed very little amplification, and sounded amazing.

However, the simple truth is that what sounded so good was the drum-room interface – as much the sound of the room as the drum.  Chances are slim to none that you’ll be recording the kick in this sort of room.  More importantly, even if you have a nice live room, you have to realize that the microphone hears differently from your ear.

This topic could fill a book, but, in a nutshell, when you’re in a live room with an instrument, your brain can decode the sound of the instrument and psychologically “filter” the sound of the room.  A room mic has no such filter.  It captures all the sound of the room, so that when you play back in a different room, your brain can’t filter out the source room.  That’s the room mic.  A close mic doesn’t “hear” the room at all, so the very attributes (boominess, for example) that make the drum sound good in the room probably sound terrible if the room isn’t part of the equation.

For these reasons, I usually prefer to remove the front head altogether, although I’m always open to leaving it on and working with the sound.  However, my experience is that usually, it’s better when it’s off.  Use some tape on the front head hardware to prevent buzzing and rattling.

Also note that the beater is often noisy.  It seems like most beaters squeak or rattle.  It’s shocking how these ugly sounds can work their way into a mix.  One time in a hundred, it’ll sound really cool.  The other 99 times will suck.  Get a good, quiet beater.

Note that most of these complaints are either irrelevant or even incorrect for live gigging.  For that reason, most drummers’ kits that sound good live don’t sound good in a studio.  That’s why I’d encourage you to get a kit, or, at least a kick and snare that you can tune up specifically for your studio and the kind of music you typically work with.  I’ve found that having a good sounding drum kit always at the ready is one of the most productivity enhancing elements of my studio, and ensures that I don’t end up having to record drums that sound like hell.  Remember: nothing makes your mixes sound professional like a good sounding, well-recorded drum kit.

An Uphill Battle

Knowing the sound you want is only half the battle. The next question is: how will you know when you actually are getting the sound you want?

Bass response issues are the most prevalent monitoring problems in all studios. It’s worse if you’re a home recordist in an untreated room using the typical semi-pro monitoring solution. The bass response in your room is almost sure to be wildly inaccurate. Consider this response curve from the typical bedroom studio:

There is almost no way at all that you can tell what the drum really sounds like. When you play a kick drum in this room, you aren’t hearing the drum. You’re hearing the room’s resonances. Headphones won’t help much, because headphones have a similarly exaggerated bass sound. Headphones are probably flatter than the room, and with lots of practice you might be able to start to get an acceptable reference from them, but it’s still mostly just shooting in the dark.

So you just have to have a good monitoring system and a lot of room treatment. This article won’t go into the specifics of room treatment, because that’s covered well elsewhere. But the point is: without an accurate monitoring system (including room) you won’t know if the drum sound is good or bad, and can’t make informed decisions. It’s just impossible to know what’s going on with a kick drum.

Control room isolation is also important. Chances are that if you’re trying to EQ the drum while the drummer is playing, unless you have good isolation in the control room, a lot of the deepest bass is bleeding through into the control room, making the drum sound a lot bigger than it really sounds in the recording. You’re going to have to record test tracks and adjust based on playback.

Now that we’ve covered the basics, we’re going to assume you have a reasonable acceptable drum and a reasonably accurate monitoring system with which to hear it. Now what?

Close Miking

You need a mic that can reproduce bass well and which is matched to the needs of your recording. Popular mics for this application are the AKG D112, Shure SM7, Sennheiser MD421, or even an Audix D4 or Audio-Technica Pro25. Dedicated kick drum mics are good in general, because they’re designed to capture the deepest bass and to withstand the intense sound pressures in a kick drum. But MD421s (an all-purpose mic) are great on kick, as are lots of other mics, even SM57s. These mics usually have less deep bass and more “snap” than dedicated kick drum mics, which may be exactly the right sound for your mix.  But don’t use a large diaphragm condenser in a kick.  Chances are you’ll damage the transducer.

The kick drum mic is usually placed a few inches back from the head, pointing towards the spot where the beater contacts the head. I usually place the mic 4″ back, 2″ off-center, pointing sideways towards the contact point. This seems to give a more balanced bass response. But sometimes the right spot is further back, or closer, or more in the middle, or even a couple of inches outside the shell. You have to move it around and listen. The sound inside the drum is highly variable.

You will usually -but not always – want to hear just a little tone. If the sound is all “slap-punch” but no “boom” at all, it may be a little too dry sounding in the mix. But the tone should usually be minimal, not loud – sort of an “aftertaste”, not a primary flavor. Adjust the damping in the drum to adjust the tone. I prefer a soft pillow set in the bottom of the drum, held in place with something heavy (I use a mic base). Push it a little harder against the head for more damping, further back for less.

Not getting enough “slap” in the sound? Consider a few drum tune-up tips before reaching for a different mic or EQ:

  • If the drummer has a “falam slam” or other contact patch on the head, try removing it.  I only use these for live applications to prevent breaking the head.  I’ve never thought they sounded better.
  • If the head is brand new, turn the drum on its side and (carefully) apply a lot of pressure to the drum. If you’re not too heavy, you can almost stand on it. Bounce a little on it to stretch it.  If the head is really new and elastic, there’ll be a low slap/tone ratio.
  • If the beater is very soft, replace with hard felt or even a wood beater.
  • Does the drummer really kick the drum hard? Unless the song really requires a dynamic kick (like jazz or smooth vocals) the drummer should kick the drum hard. A lot of drummers don’t have a hard, consistent kick. That takes practice.
  • Is the drum tuned too high or too low? I usually get the head just tight enough to produce tone, then tighten up “a little more”. If it’s really tight or loose, that’s going to affect the slap-to-tone ratio.

Not getting a good tone? That’s a little easier: just tune it.  Start by tuning the drum up or down a little before reaching for EQ. And adjust that pillow and move the mic around. You may find that a little change produces a significant result.  If you can’t get it in tune, or notice any dimpling or obvious signs of head fatigue, change the head.

Some engineers like to mic the front side of the head.  I don’t.  The point of a close mic is to isolate the sound of the individual drum, and the front side mic will usually have as much snare as kick.  And the only thing you can get from the front side that you can’t get from the back side is a little more top-end snap.  I’d rather work with the drum to get that sound than try to wrestle with a front side mic.  Of course, if you have a kit and a front-side mic that works for you, that’s great!  Go for it.

Distant Miking

I always use some kind of room mic setup when I record drums, and the main thing I’m working on is the kick and snare – mostly the kick.  That’s why I think of my room mics as distant kick mics.  I like to get a room mic that focuses on the kick and truly jack it up with compression.

A lot of engineers like to submix their drum tracks into a compressor and blend that back in with the uncompressed drum mix (discussed below).  However, I prefer to do a similar trick with the room mic when tracking.  Often, I’ll use a single mic about four feet in front of the kick drum (head off).  I like large diaphragm condensers (like a Telefunken ELAM 251) or a robust dynamic mic (like an MD421, probably my favorite) for this application.  Usually I’ll use my dbx 576 preamp / compressor for this application.

The goal is to really capture the “roar” of the kit, and to use compression to exaggerate the attack of the kick and snare.  I’ll usually scoop out some low-mids (around 250 Hz) and roll off just a little treble to de-emphasize the cymbals.  Then I’ll compress the snot out of the track with a 4:1 compressor, and sometimes even hit the limiter just a little.  I’ll make sure the attack and release settings allow all of the transient to come through, so the kick (and snare) have a pronounced snap to them.

The reason I prefer to effect the sound while tracking (rather than when mixing) is because there is so much interactivity between the mic, its placement, the EQ, and the compression that I want to know that I’m getting a sound I can commit to before I track it.  When done right and placed behind the overall drum mix, this track is like a steroid injection.  The drums will have more energy and attack, but not sound really effected.

Since my room mics are all about the kick drum, I find it important to phase-align the room mic with the close-miked kick.  I don’t usually worry about doing this with any of the other mics.  In your DAW, just move the room mic forward in time so that the primary peaks coincide.  If one is out of phase, flip the phase so that both tracks are creating positive initial swings.

A lot of engineers prefer a stereo room miking setup.  When you room-mic the kit in stereo, you’ll usually be trying to capture more of the sound of the room, so you’ll be much further back and higher up.  This can be a great sound, but will focus less on the kick and more on the rest of the kit.  This can sound good, but I’m a “kick-snare” freak, and prefer to use my mono mic setup in front of the kick drum – it really locks in the center image and creates a very punchy kick.

As a matter of fact I have done mixes that only use this single mic.  A notable case in point, as well as an utterly shameless plug, is the track “Freedom” from my 2006 release, “Rhythm/Pleasure 2”.  I played the drums on this track, recording the kit with a single ELAM 251 about 5 or 6 feet in front of the kick (as in the photo above) into a dbx 576 (as described above).  I basically just distant-miked the kick, and needed no other microphones at all on the kit.  Of course, this doesn’t produce a pretty, photographic stereo image of the drum kit, but I think that, for this track, the compressed, focused mono sound – with its tight, punchy kick – did just the trick.  I also like the minimalism this approach offered in what was otherwise a sonically over-the-top mix.

EQ It

Now let’s talk about EQ. Like a surgeon preparing for the first cut, you can perform miracles or kill the patient. With a good sounding kick drum, sometimes I need no EQ at all. That’s best case. Usually, I need some EQ. I start by managing the deep bass. A useful tool here is the high-pass EQ. You want an EQ that emulates a “real” EQ curve. Examples include the Sonitus:FX EQ and the Waves Renaissance EQ. Apply a high-pass EQ and set it around 40 Hz. As you turn up the Q control, you not only cut the low bass off more sharply, but you also produce a boost just above the EQ turnover point. This is very effective for emphasizing the fundamental of the kick while reducing the elephant farts that suck power out of your drum sound.

I often set the turnover point just below the fundamental, so that the boost emphasizes the most powerful frequencies in the drum. But sometimes, if I want a tight sound, I’ll set the turnover higher, around 80 or 90 Hz. This can give that powerful hit-you-in-the-chest sound, but it’s also likely to produce a muddier sound. To hear what you’re doing, turn up the Q until you can really hear the boost frequency, and sweep the frequency slowly, listening for the effect. Use only the smallest amount of boost that you can get away with.

I often like to pull out some low-mids, to give a little more room for guitar, vocals, and bass. Setting the low-mid EQ around 300 Hz, with a moderately wide Q setting, pull out a few dB. Pull out the low-mids until the drum is hollowed-out sounding so that you can hear what you’re doing to the drum. Now add the mids back so that you’re only reducing the low-mids by the smallest amount you really need.

A gentle high-shelf is useful to bring out the “slap”. Set the frequency to around 1.5KHz and add 1-3 dB. You’ll hear the slap come up a little.

For now, I encourage you to only make moderate changes to the EQ. Push it in the direction you want it to move, but don’t try to get it there all at once. We’re going to make some more changes with compression.

Compress It!

It’s almost impossible to offer a compression prescription for kick drum.  If I’m using the distant mic on the kick, I rarely compress the close mic.  When I do, it is to increase the attack of the drum.

There is a widespread misconception that the purpose of a compressor is to decrease dynamic range.  If you believe that, then you don’t understand compression.  Compressors can increase dynamic range just as easily as they can decrease it.  The secret is in the attack setting, and that’s how I use compressors to add attack and dynamics to the drum sound.

To hear the effect, add a compressor set with a 10-15 ms attack, a 150 ms release, and a 4:1 compression ratio onto your kick drum track. Now crank the threshold way down to hear the effect. You’ll hear the attack-to-tone ratio really increase. Now adjust the threshold so that you’re getting the attack-to-tone ratio that you want.  You are increasing the dynamic range of the drum.

The other consequence of this compression is to increase the length of the sustain. Since the compressor will release over the length of the sustain, this has the effect of turning up the volume along the length of the sustain. Adjusting the release can help here, as can adjusting the pillow to be a little tighter (or looser) to taste.

Play with the compressor. You can achieve lots of change in the sound with the compressor. Usually, however, I don’t use much compression on the close-miked kick drum track, preferring to get the attack from my distant mic setup.

Give it Space

If you listen to kick drum sounds in recordings you like, chances are you’ll notice a little room ambience. The kick & its ambience is probably not completely mono, but has a little stereo spread. A good stereo room mic pair is a great way to get this, but getting a good room sound involves… yes, a good-sounding room, good mics, and lots of practice. And, it’s going to change the sound of all your drums. I often use room mics. Here again there are no prescriptions. It totally depends on your room and what mics you have available.  This is one more reason to have your own kit and to take a lot of time tweaking it and your mic rig to get the results you prefer.

Another, more predictable method is to use a good digital reverb. Even on kick drum sounds that I want to be “dry” I’ll usually add a little ambience with a reverb. I use a short reverb, like a short room sound. I’ll usually increase the “space” or “width” control of the reverb to exaggerate the stereo spread, and turn the reverb down low, so that it’s barely audible. Also experiment with putting the reverb in front of the compressor instead of after it. You can get some cool, powerful effects this way. The increased stereo spread and slight ambience will make the drum sound just a little bigger in the mix, even if it’s low enough to not be particularly audible.

Submix It

One useful trick is to split the signal to a separate submix bus, and do some exaggerated EQ, compression, and reverb on the split signal. Then fold a little of that back into the sound. Try doing some whacky EQ boosts or cuts, then compressing really hard. Consider some whacky reverb before the compressor so that you’re getting a really intense explosion of sound. Now fold just a touch of this back into the mix. Done right, this can add some cool energy and intensity to your mix, even if it’s subtle enough to be almost unnoticeable in the mix. Instead of using your kick track as the source, try using the room mics as the source, and filter out the high end altogether so that you’re working with just a big slab of ugly, effected, stereo bass.  Experimentation is the key.

Rescuing the Victim

Suppose you have a great performance, but a lousy kick drum sound?  Fortunately, the kick drum is the easiest drum in the kit to rescue with a little sampling magic.  Don’t turn your nose up at this solution.  More of your favorite music has been altered with samples than you realize.  It’s easy, and the truth is, it can sound really good.

Tools like Drumagog and Drum Rehab offer a decent solution.  These tools detect the transients in the drum track which are used to trigger samples.  Other tools like Sonar offer transient-to-MIDI capability that can be used to trigger MIDI hardware or software samplers.  With the right samples you can truly save a dying patient right on the operating table.

Let me tell you of an extreme case.  I had been given a final mix of a song that, in most ways, sounded great.  It had this cool, live, raucous garage feel that was perfect for the song.  Turns out it had been recorded live on an 8-track in this guy’s living room, which was why the sound was so present and immediate.  Unfortunately, for whatever reason, there was almost no kick drum at all in the track – or in the source, so even a remix wouldn’t solve the problem.  The musicians were really depressed because it was a great, unique performance of a cool song that sounded bad because of only one significant flaw.

I loaded this mix into Sonar into two stereo tracks.  One track held the original mix.  On the other track, I used a couple of EQs, a limiter, and a gate to isolate what little kick drum was in the track, choosing a frequency that stood out above the bass guitar.  I created a track that was just a very short noise blast with every kick, and used Sonar to detect these transients and replace them with an appropriate sample.  By finding a reverb that closely matched the live sound of the room the rest of the drums were recorded in, I was able to blend the sample kick back into the original mix in such a way that it sounded just like the rest of the kit.  The result was that the song sounded great, and the band was dumbfounded.

Conclusion

Hopefully, this article has provided you with some inspiration to improve the sound of your kick drum tracks.  If you have some of your own favorite techniques, let us know.  And stay tuned for Part 2, where we’ll beef up your snare sound.’

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