Last month, part one of this series explained the different types of mics, polar patterns and basic techniques, but now it's time to discuss some specific recording methods. In any discussion on microphone placement, you're bound to hear about close- and distant-miking. At only a few inches from the source, close-miking naturally focuses on the direct sound and less on the surrounding room acoustics. That is ideal for capturing a fuller, tighter sound with minimal leakage being picked up from other instruments. Together with appropriate polar-pattern selection, this also means that less coloring ambience enters your tracks, possibly making it easier to match up various takes of the same voice or instrument if recorded in different studio environments. Stereo recordings of solo instruments can also benefit from close-miking due to the increased separation.
Backing out anywhere from 10 to 12 inches to several feet or more from the sound source, distant-miking reveals more ambience and depth to the recording. It can also be used to achieve a sense of natural compression because fewer dynamics are picked up. Many times, both close and distant microphones will be used in tandem and later mixed for color and ambience balance. One danger in placing two or more mics on a single source, however, is the risk of phase cancellation. For that, almost every recording engineer will employ the “3-to-1” rule, positioning the most distant microphone at least three times farther from the sound source as the closest mic. In situations where the close microphone is literally an inch or two away from the sound source, the spacing ratio becomes 4-to-1 for the distant microphone.
Note that most close-positioned microphones sound drastically different as they're moved ever so slightly about the source, or as the source moves ever so slightly about the microphone. That is especially true with highly sensitive condensers; as you make the microphone more distant, these variances become less apparent.
Another trait of extreme close-miking is something called the proximity effect. Though the effect typically begins at a distance of about two feet, directional microphones will experience a significant boost in the low-frequency response when a sound source is within an inch or two of its capsule and diaphragm. Many experienced vocalists use that to their advantage as a type of natural dynamic EQ, adding fullness to their voice; it's also used to add punch to amplified guitars and basses. However, the effect detrimentally emphasizes low-frequency breath sounds and causes vocal plosives, such as “p” and “b,” forcing the use of pop filters. And of course, always try to use manufacturer-supplied shockmounts whenever possible and/or practical.
A NICE PIECE OF KIT
Drums can be miked in any number of ways — from a mere pair of overheads to one or two microphones on every single piece within the kit. Regardless of how elaborately you mic a drum kit, though, it's best to keep in mind the golden rule that the kit must act as a whole and not as a sum of individual parts. That is, the sound of the overhead microphones should always be your priority — analogously thought of as a wide-screen image of the kit's overall picture — with spot microphones acting more like close-up shots. Indeed, the close mics are there to accentuate certain frequencies, sharpen the attack and bring focus to the placement of a kit's individual pieces across the stereo sound field of the overheads. With the following advice, I assume you're looking to minimize leakage and have highly present, well-isolated tracks for mixing/remixing.
Starting on kick, place a large-diaphragm dynamic mic inside the drum, aimed just a couple of inches away from the inner head and just slightly off-axis to the beater. If you want a meatier sound with less click, just pull the microphone back a few inches and place it midway in the drumshell, facing more toward one side. I like the Audio-Technica AE2500 ($699; www.audio-technica.com) dual-element cardioid instrument mic for this job, which combines condenser and dynamic capsules into one and can really dig into the low frequencies without blowing under high sound-pressure levels (SPLs). For recording truly fat and funky hip-hop or dubby jazz loops, I've actually brought in a large orchestra bass drum and set it next to the kick so it could ring sympathetically to give more low end, instead of the commonly employed trick of adding a suboscillator to the kick track during mixing.
You can also try augmenting your close-miked sound by additionally placing a nice tube mic around 12 to 14 inches in front of the outside head of the kick. Leakage from the rest of the kit will now become an issue, however, so you'll want to construct a 4- to 5-foot-long drum house (aka tunnel) to isolate the outside microphone of the kick from as much cymbal and snare bleed as you possibly can.
On snare, I like to start with a Shure SM57 ($158; www.shure.com) mounted about 1 to 2 inches above the rim and aimed toward the center of the head. In addition to placing the mic off-axis to the hi-hat, try placing a 6-by-6-inch piece of carpet padding just behind it (cut a slit in it to slide over the mic stand) to provide a tiny bit of added isolation from the hat and cymbals. For the bottom mic, I like to set a condenser relatively close (2 to 3 inches) from the snare with its back to the kick drum and its pattern set to cardioid to minimize bleed from the kick.
Though many engineers will only bottom-mic toms, I prefer to use a close-miked dynamic on the high tom and condensers on the mid and floor toms, each mounted facedown about two to three inches from the top head. That captures more present attacks. Regardless of microphone type, try to save the largest capsule mics for the lowest toms.
You can use dynamic mics on hats if your microphone stash is limited, but I prefer the sound of a cardioid condenser facedown and 2 inches above the hat. Try positioning the mic so that the hi-hat itself is a natural sound barrier between the mic and the snare. Again, use a piece of carpet padding slipped over a spare gooseneck stem or a clothes hanger duct taped to the mic stand for extra isolation from the cymbals sitting right next to the hat.
A misnomer about overheads is that they're only for picking up cymbals. In fact, they're there to capture the overall kit, as well as the room to a certain degree. The overheads are the sound of your drums, so that is where you should use your best studio condensers, equally raised on booms a few feet above the kit and stereo-positioned one left and one right. Use your best preamps as well. Spot-miking the ride with a cardioid studio condenser aimed 45 degrees off-axis to the bell should cut through nicely. A good trick is to put that mic on a slow-release gate during mixing, so it only opens when the drummer is actually playing. Because the ride hardly ever cuts through the overheads, a mic positioned like that will really save you in the mix and let the ride come through loudly. This is also particularly helpful if your drummer sets the ride cymbal lower than the other cymbals because the ride will be overpowered by the crashes.
In modern production styles, there seems to be a million ways to mic an electric-guitar amplifier. Though the tried-and-true method is to use a sturdy dynamic mic like the Shure SM57, many modern condensers and even ribbon mics can easily stand up to the punishing SPLs.
Classic positioning would have a dynamic mic very close and aimed directly at the center of the cone for maximum high-end “British” crunch. While aiming it slightly off-axis achieves a warmer sound, most engineers agree that the sweet spot seems to be where the speaker cone and dome meet. Close-miking like that produces a very in-your-face sound. Moving the microphone back from the grille cloth, you can experiment with the proximity effect by fine-placing the mic closest to the speaker to achieve enhanced lows, fewer lows as you move away and diminished highs as you orient the mic more off-axis or slide it toward the edge of the speaker cone for an even duller sound. To incorporate a little more room ambience to your sound, try changing the polar pattern from cardioid to omni. A “clean” amped guitar sound is best achieved with the microphone set to cardioid and placed 1 to 2 feet from the speaker, on- or slightly off-axis, being careful not to overload the microphone.
For a rounder, beefier “American” sound, you might want to try a condenser mic and a dynamic mic simultaneously, recording them to different tracks and either picking or blending between the two feeds at mix time. That also works wonders with dual-speaker amps, where you can aim one mic straight at the cone-edge sweet spot of one speaker and aim the other mic pointed off-axis at the second speaker; that allows you to blend the crunch tone of one with the fuzzy warmth of the other. When bi-miking an amp, though, it's imperative to keep the microphone capsules positioned the same distance from the speakers for the best phase coherence.
Another widely used method is to combine one microphone behind an open-back cabinet with another at the front, for that large “cab” sound. Unless your recording room is conducive to great acoustics, you'll probably want to keep the mics set to cardioid and aimed toward each other, flipping the polarity of the back mic to counter phase cancellation.
In general, pricier small-diaphragm condensers with omnidirectional response are best for capturing acoustic instruments close-up for their extended high frequencies, smooth characteristics, low susceptibility to proximity effect and no off-axis coloration. But many engineers swear by dynamic microphones as well. For the average-sounding bedroom studio on a budget, there's nothing wrong with using a decent-sounding large-cardioid condenser — preferably a tube — or ribbon mic.
For a natural-sounding acoustic guitar, careful mic placement is crucial so that you avoid a boxy, overly resonant sound. Though acoustic guitars primarily project through their sound hole, this tone is overly colored by the resonance of the guitar's body. Instead, I'll try to capture a more pleasing balance of body, string, sound hole, neck/fret-board tone and room ambience.
In a single microphone scenario, a small- or large-diaphragm condenser is placed at the classic positioning of the 12th fret with the capsule pointing slightly up the neck (or to where the neck joins the body) and with its polar pattern set to cardioid to reduce the boominess from the sound hole. That is a common bedroom setup because it rejects the standing waves and early reflections bouncing off close, parallel-plated walls, and it captures a cohesive blend of the entire instrument rather than merely the sound hole. If you're picking up the guitarist's breathing, sniffs and snorts too much, try positioning the mic somewhere just above the low E string and tilt it downward but still aimed at the same angle up the neck. As for distance from the guitar itself, try setting the microphone 15 to 16 inches in front for a more integrated sound, where the levels of direct and reflected sound should be just about right, even in nonideal rooms. Close-miking — one foot or closer — will emphasize the upper midrange and produce a crisp, harder sound that is complementary to pop music. Indeed, you may find yourself moving the mic all over the place to find the right tone for a given track. As a general rule, the closer you move the mic toward the neck, the less bass and softer attack the sound will have, while venturing closer to the bridge will bring more warmth and fullness to the sound without sounding tubby, as well as more brilliant highs and crisper attacks.
Another option is to position the above mic in front of the sound hole, oriented off-axis toward the bridge, with a second condenser aimed at the mid fret board (around the 6th fret) to pick up string noise; again, cardioid for both. Once recorded, that combo can be mixed either in stereo or more for tonality as an extremely rich mono signal. For even more elaborate stereo recordings, position two condensers in an XY configuration, mounted on stands horizontally so that their capsules are the same position and distance from guitar, mounted on top of each other at 90 degrees and facing the guitar in off-axis fashion. Finally, you can use spaced pairs, using one mic over the guitarist's shoulder and another 8 or 12 inches from the middle of the guitar neck, delivering a sound similar to what the player hears with more string tone from one side and more pronounced lows from the other.
In all of these cases so far, the guitarist must remain fairly still in his chair or pickup patterns will begin to smear wildly. As a backup plan, try clipping a miniature (Lavalier or “tie-tack”) mic inside the guitar.
SILKY STRINGS, BRASS BALLS
Stringed instruments such as violins, violas and cellos need room for their rich and full resonance to build. For this reason, you don't want to close-mic these instruments. Similarly, omni-pattern microphones are excellent for distant-miking horn and string sections because they allow for full room interaction to come through on the recording. The best way to capture a small string ensemble is to place two cardioid microphones in an XY configuration, positioned on a long boom several feet above the players' heads. To bring out the inherent low end in deeper instruments such as cello or stand-up bass, you'll benefit from using a large-diaphragm condenser. When close-miking brass, simply aim a dynamic mic directly at the front of the horn for clear, sharp notes filled with lots of high-end transients, or at 45-degrees off-axis to the bell for warmer tone variations.
Miking a piano can be tricky, and it is best approached based on the style of music and the part being played. But you can borrow from theory already discussed here and assume that closer-miking (under the lid and directly over the soundboard) will capture a brighter, less reverberated sound that should cut through a pop track, while mid placement of microphones adds more room-influenced body and fuller harp/soundboard tone. Unless your room has amazing acoustics, distant-miking might turn your piano into nothing more than a haunting special effect. Using one microphone, my foolproof method is to suspend a small-diaphragm condenser from a heavy-duty and shock-absorbing microphone stand, such as the Atlas Sound air-suspended SB-series (www.atlas-soundolier.com), directly over the middle of the soundboard. With the lid wide open and angling the mic so that each side of its figure-8 capsule points to the high and low strings, what you end up with is a rich and equally balanced mono piano signal that really cuts and is ideal for most modern piano tracks. When close-miking like that, there's no need to match microphones, so I'll often add a dynamic for the bass strings and use the condenser for the treble, either mixing them to mono or gently spreading them to mimic the sound of sitting at the keyboard.
This miking series wraps up next month with advice on microphone signal paths. For an extended version of this article with sections on vocal miking and mic-placement term definitions, go toremixmag.com.