Paul White explains that although we may do most of our work using samplers and sequencers, the art of drum miking is just as important as it ever was.
To study drum miking in depth could take up a whole book, but just a few simple rules and guidelines will ensure that you get high‑quality results from whatever equipment you have. The ability to record a real drum kit is still a valuable skill and one that no engineer should be without; even in this sampler‑dominated world, you need to know how to record drums if you ever want to sample them. This is especially important when sampling live drums for looping, as you have to take into account such factors as balance, tuning, crosstalk between the various drum mics, choice of reverb treatments, and so on.
A good drum sound starts with a good‑sounding drum kit. Providing the kit is fitted with newish heads, it should be possible to coax it into sounding halfway decent fairly quickly. On the other hand, if your heads have more wrinkles than Victor Meldrew's bottom, no amount of tuning and damping will bring back the tone.
Miking Up
Having got your kit tuned, the next decision is how to mic it up. The simplest way is also the most accurate — but accuracy isn't necessarily the most important criteria. A stereo microphone pair (usually spaced a few feet apart) placed between five and 10 feet in front of the kit will convey the live sound of the kit very accurately, but any natural imbalance between the drums or any unsympathetic room acoustics will also be recorded faithfully, so you may have to move the mics a little closer to exclude some of the room. As to what type pf mic to use, even the cheap Tandy PZM mics work well in this application. However, because of their operating characteristics, they should be mounted on a wall or large board in order to do justice to the bass end.
For pop work, simple stereo miking often produces a result lacking in the power and immediacy that comes from close‑miking individual drums, so a good compromise is to use further close mics on the bass drum and snare. The snare mic should be placed a couple of inches above and from the edge of the top head. A unidirectional (cardioid) dynamic mic is the usual choice, though some professionals might choose a capacitor mic in order to get a brighter tone.
The bass drum mic should also be a dynamic cardioid, ideally one specifically designed for use with bass drums, positioned inside the drum and pointing towards the spot where the beater hits. If you don't have a suitable stand, you can get good results simply by lying the mic on top of the damping blanket.
Close Miking
Close miking seems to be the accepted way of getting a pop drum sound, and though it doesn't sound much like a natural acoustic kit, it's the sound we've all come to expect. My own theory is that this sound evolved from the live concert sound of the early '70s, when drum kits were miked up to enable them to compete with ever more powerful backline and PA systems. Close mics had to be used to avoid spill, and because records of the time attempted to emulate the live sound of touring bands, the same mic techniques were also applied in the studio.
Snare drums are the brightest drums in the kit, so either a dynamic mic with a good high‑end response or a capacitor mic is the best choice. Even toms produce bright attack transients, so use the best mics you can get hold of; good dynamic cardioids such as Shure SM57s or Sennheiser 421s (cardioid pattern mics give the greatest immunity from spill) are the most popular choice. The usual mic position for the toms is a couple of inches above the drum head, a couple of inches in from the edge, and angled towards the centre of the head. This is more or less the same as for the snare drum. Any damping should be placed out of the way of the mic.
To capture the cymbals, and to bind the overall sound of the kit together, we still need a pair of stereo mics, often called overheads because of their favoured position. Capacitor or back electret mics should be used in this role, and in most cases, you'll find you pick up enough hi‑hat without needing a separate mic.
If you want to record a hi‑hat on its own — for sampling, say — position a capacitor or electret mic 6‑12 inches from the edge of the cymbals and about 6 inches above, angled so that the mic is 'looking' at a point halfway between the edge and centre of the cymbal. Figure 3 shows the position of a separate hi‑hat mic.
Ethnic percussion is best miked in stereo from above, at a mic distance of 1‑5 feet, depending on the instrument and the contribution of the room acoustics. Using a capacitor mic will produce a more accurate, detailed sound, though, again, the Tandy PZMs can produce excellent results. For sampling in mono, a single mic is adequate. Because the room sound has such an influence on the end result, it pays to experiment by checking the sound in different rooms, and by putting hardboard over any carpets. Bringing the mic closer to the instrument will reduce the effect of the room, but moving too close may result in an unnatural sound. You can also emulate talking drums and tablas by sampling a suitable fixed drum sound and then playing it back using pitch bend.
Hybrid Approach
Hi‑hats and cymbals from even the best drum machines and samplers can sound just a little too regular and mechanical to be convincing (except for use in dance music, where this is more acceptable). Many producers like to mix electronic drums and percussion with real cymbals to produce a more human feel. Of course, you can take a halfway approach and record a loop of real hi‑hat playing, which can then be sampled. The slight timing fluctuations of a real player make the whole thing sound more convincing, but you still retain the advantages of electronic drums: good separation, controllable dynamics, choice of sounds, tight timing and so on. To record cymbals only, all you need is a pair of overheads or wall‑mounted PZMs, and if you just want to work on the hi‑hat, a single capacitor mic set up. A useful tip is to roll off some of the bass from the cymbal track, as this can remove some of the 'gonginess' that sometimes creeps in when using less than perfect mics or cymbals. Adding 'live' tom fills to a machine‑generated backing rhythm can also add a welcome degree of feel and humanity.
Summary
By now I hope you'll feel confident enough to have a go at miking up drums should the need arise, even if it's just to add sounds to your sample collection. Some people worry unnecessarily about drum recording because such as mystique has been built up around the subject, but as with most aspects of recording, 90% of the battle is getting a good sound at source. Good mics produce better results than cheap ones, but on some of my very early 4‑track recordings of drums made using just dynamic vocal mics and a Great British Spring reverb, the drum sound was actually quite acceptable. More important by far is the way the drums are tuned and played, and where you place the mics. You don't even need fancy effects — even the cheapest digital reverb will out‑perform the best of the old spring units as far as drum processing is concerned.
Creating sample loops based on live drum parts can improve the feel of a piece of music beyond recognition, so if you're one of those people who live their life by the quantise button, try getting a real drummer in and see just what a huge difference it can make. I almost forget to mention that the subject of drum recording (along with most other aspects of recording) is treated at great length in the recently published tome Recording and Production Techniques by some guy named White.
Basic Tuning
If you don't have any experience in tuning drums, it's best to leave the job to an experienced drummer, but if you want to have a go yourself, here are a couple of basic tips.
- Keep in mind that a drum has a natural pitch, and if you over‑tighten the skin or head, the tone will become 'ringy' and lacking in power. If the skin is too loose, then the sound will lose its resonance — you soon an idea of which pitch sounds best.
- Ensure that the head is evenly tensioned all round. You can check this by tapping around the edges of the head with a stick while adjusting the tensioners until you have the same pitch all the way round. Once you reach this stage, tune the head by making small adjustments to first one tensioner, then the one opposite before moving round the drum. Single headed drums (snares excepted) are the easiest to tune, though if you prefer the sound of double‑headed toms, the bottom head often needs a little damping to prevent it ringing.
- In the case of snare drums, the snare (bottom) head is generally tensioned slightly looser than the batter (top) head, though different drummers have different preferences. The snares will vibrate in sympathy whenever another drum is hit, and though this may be reduced by careful tuning of the snare drum, some buzzing is inevitable. If you're recording one drum at a time to produce samples, you can turn off the snares when they're not needed, or you can even work with just one drum in the room at a time if you want a really clean sound, but if you have to record the whole kit in one go, you'll have to live with a few rattles and buzzes.
- If damping is needed, this is usually achieved by taping folded tissue or cloth to the edge of the top head of the drum, but be careful not to overdamp because you'll end up with a sound like somebody hitting a suitcase. It's easy to get paranoid about rings and buzzes, but you'll be surprised at how these disappear when the rest of the mix has been added.
- In the case of the bass drum, most rock and pop drummers will have a hole cut in the front head to produce a louder, more punchy sound. This is better than removing the front head completely which risks distorting the drum shell. A wooden bass drum beater gives the most 'smack' and the definition can be increased further by taping a piece of plastic to the head where the beater hits. The plastic token cards given away by petrol stations are ideal for this purpose so start collecting them now! Failing that, your significant other's credit card will do the same job and save you money into the bargain. For damping, just place a folded woollen blanket inside the bass drum; to increase the damping push the blanket so that it contacts more of the rear head. Noise gates are useful to tighten up bass drum sounds, as a surprising amount of spill from the snare drum and toms gets into the bass drum mic.
To digress slightly, why is a bass drum called a kick drum? Simply to avoid confusion when you write all the instruments on your mixing desk's scribble strip. In the old days, people would write 'bass' for both bass drum and bass guitar which presents obvious problems.
- Finally, the room itself has a significant effect on the sound of a drum kit, and a hard floor gives a more lively sound than carpets. If you're stuck with a carpeted room, try placing a couple of sheets of hardboard on the floor under the kit to reflect some of the sound back up. Individual drums or other percussion instruments can also sound good miked in bathrooms or concrete stair wells, so check out your local schools, museums and swimming baths to see if they are amenable to letting you record a few samples after hours.