Fig. 5: The area on any drum head nearest the rim will ring freely and have a preponderance of high harmonics. The area between the rim and center will produce the most resonance, and the area at the center of the drum head will sound driest and produce the most attack.
To dampen toms, tape a folded cotton handkerchief, a small rectangle of foam rubber, or some similar material (tissue, cotton gauze) onto the top of the drum head, close to the rim and away from the drummer. In most cases, a small amount of material taped an inch or so from the rim is sufficient; to increase dampening, move the material toward the center of the drum, use more material or do both. Tip: use sturdy masking tape or some other type that's easy to remove — duct tape will muck up heads and hardware. (See the sidebar “Engineer's [Secret] Drum Toolkit” for some useful items to keep on hand.)
THE ROOM
Along with making the kit sound its best, you also have to consider the recording space and how it affects the drum sound. Sound can't exist in a vacuum; it is always part and parcel with the surfaces reflecting it (an effect made eerily clear in anechoic chambers, in which you can hardly hear yourself speak). The drum set is usually played loudly, making room reflections more apparent. The room can't help but be a component of the drum sound; it's impossible for its “sonic imprint” not to appear on the tracks. Without fail, you will be working with — or against — that imprint at every stage of the mix.
In short, the kit has to sound good in the room. Fortunately, this part of the puzzle can be enhanced with practically no knowledge of acoustics. You just need ears and a willingness to experiment.
The goal is simple: find the place where the drums sound “best” in the room. Of course, if they happen to sound great just where they're sitting, then you can advance directly to Go. The idea, after all, is to improve the sound. Just as the slightest movement of a microphone can result in a big change in what the mic hears, relatively small changes in the orientation of a drum kit inside a room can make significant differences in the overall sound.
Fig. 6: All directional mics naturally form a null point, or an area at which no sound is picked up, behind the front of the diaphragm. This can be used to your advantage when you need to isolate one mic's pickup from another's—a most useful technique on close-miked drums.
Sure, moving the drums from one spot to the next can be a hassle. But if you care about getting the best sound, it's worth it. Finding the “sweet spot” for the drum kit is something that can hardly be done without experimentation. True, the more you do experiment, the easier it gets, and in time you will develop a sixth sense about it. (Experienced drummers often instinctively set up in the best-sounding spot.) But ultimately, rooms are quirky and unpredictable, and you'll find that experimentation will yield surprising results.
The main thing to listen for is a favorable balance between the kick, toms, and snare drum. Turn the snares off so you can better hear the drums ringing. Is anything noticeably out of whack in terms of volume, resonance, or decay? If so, try a different location. Does one of the drums cause the snares to buzz excessively? Repositioning the drum set — or just that one drum — might solve the problem. Is the kick drum lacking in oomph? Try setting up the kit so that the drummer sits in a corner looking out into the room (assuming a rectangular room, that is). Are the toms sounding thin? Try pulling the kit more toward the center of the space. Is the room just not working for you? Then find another. I have rented church halls (surprisingly affordable), warehouses, and art galleries to get the drum sound I was after.
The other side of the coin is acoustical treatment for the room. You can tame, for example, nasty flutter echoes with judicious placement of acoustical foam rubber. Don't have the budget for that? Try hanging blankets, thick curtains, or rugs from the walls or the ceiling (or both), or positioning large pieces of furniture, full bookshelves, or what have you around the room so as to deaden it. If the room is too dead sounding — a small, thickly carpeted and curtained study, for example — try such things as arranging large wood panels along one or more of the walls, setting up the drums on a wooden riser, or both — anything to provide some helpful reflective surfaces.
THE GEAR
Many assume that gear is the most important component in capturing a good drum sound; more specifically, the mics and mic preamps. Good mics and preamps are a tremendous help, but as long as the source sound is less than desirable, that's all your good mics and preamps will capture — something less than desirable.
We're trying to make drum recording easier, so let's start by paring the signal chain down to the basics. All you really need for each channel is a microphone, or mic preamp, and a track to record on. Leave your compressors, EQs, and other doo-dads for the mix. That saves time, and it forces you to find the best mic (and mic position) for the job, as well as to set the gain properly on the preamp.
Setting the gain right is no big mystery, but you do need to pay attention. While the drummer is playing at record volume, simply dial in the hottest levels you can get for each track — for the whole song — before peak distortion. That's called maximizing the signal-to-noise ratio.
Note the differences between digital and analog level setting. Analog tape has a higher noise floor (hiss) than digital recorders, so it's especially important to maximize the signal-to-noise ratio when recording to tape. After all, the hotter the signal, the less tape noise you hear.
In fact, drums are typically recorded “hot” (above 0 VU, that is) to tape to create a particular sound. The hot signals saturate the tape, which flattens out transients, resulting in a compressed sound that many engineers and musicians favor, especially on kick, toms, and snare. (Overheads and hats are usually recorded “colder,” to preserve the accuracy of transients.) You should familiarize yourself with the tape machine, because decks differ in how they handle distortion (based on tape size, tape speed, types of heads, and so on). But generally speaking, any decent multitrack tape recorder will let you run drum levels +3 or more into the red with no problem; indeed, that's where the sound starts getting good.
With digital you never want to go “into the red.” In other words, make sure that the drummer's hardest hits register close to 0 on the meters (so you use up as many bits as possible), but not above it. Unlike analog distortion, the sound of digital distortion is never pleasant. Fortunately, even if you do get a few digital peaks, you might be all right. Most digital recording devices allow a few decibels of headroom above the red before distortion kicks in. Moreover, distortion from a few peaking drum hits might not be audible anyway, due to the fast transient nature of loud hits. So if peaking is there but you can't hear it — both before and after processing the track — then don't worry about it.