Unlike the American drum set, which traditionally is played by one person and thus can be considered a single instrument, the various instruments collectively known as “Latin percussion” are typically played by several different musicians: one on timbales, another on congas, a third on guiro, and so on. This suggests a couple of things for the recordist. One, you can get away with overdubbing Latin percussion elements one at a time — something that doesn't quite work for drum-set parts. Two, recording the whole enchilada — a percussion section consisting of, say, timbales, congas, bongos, cowbell, guiro, and claves — at one time requires not only lots of microphones and space, but also considerable skill.
How do you go about recording this assortment of percussion instruments so that each timbre holds its own? I spoke with two fellow engineers who have extensive experience recording Latin percussion: Jeff Cressman, whose credits (in addition to playing trombone for Santana and Pete Escovedo) include recording albums for John Santos and the Machete Ensemble, Mark Levine and the Latin Tinge, John Calloway, Edgardo Cambon y Su Candela, Rebecca Mauleon, Columna Be, and others; and Scott Theakston, a Miami, Florida, native who teaches advanced audio engineering at Ex'pression Center for New Media and who has worked with Giovanni Hidalgo, Mas Cabeza, and a variety of salsa and Cuban ensembles.
Before the session starts, determine your approach by considering the needs of the ensemble and its music, the number of mics and channels available, the limitations of the space (or spaces), and time constraints on setup. Does the situation call for a traditional sound, which typically includes a lot of ambience (room sound)? Or would it be better to go for a more controlled studio sound in which everything is isolated and close-miked? The latter approach may be best for a band with more of a pop feel, but how far you are able to go with it depends on the gear, facilities, and time available. The traditional, more blended sound remains a classic and usually makes the most sense if resources are limited.
Assuming the music allows for it, you can also overdub the instruments one at a time — usually the simpler, more economical approach, at least for the small personal studio. But, of course, that method doesn't permit the same level of musical communication that can occur among members of an ensemble performing together. Many of the same recording techniques still apply, though.
Challenges you will face recording a percussion group at once include microphone bleed (sound from one instrument entering another instrument's mic), different sound sources competing for the same frequency ranges, and phase problems resulting from using multiple mics. These variables should influence your choice of microphones, how you position them, and how you deal with the sounds in the mix.
When recording multiple instruments in a single space, mic bleed can be controlled by a combination of two techniques: strategic use of directional mics, and arrangement of physical barriers such as gobos. Generally, the more of one technique you use, the less you need of the other.
One problem with gobos is that they can obscure line of sight between musicians — often a critical element for ensembles. Here is where careful positioning of unidirectional mics — cardioid, supercardioid, and hypercardioid — can save the day. If possible, take a look at the mic's polar-response plot to see where its null points fall (see Fig. 1). More importantly, listen carefully to familiarize yourself with each mic's rejection characteristics. That can further help you determine which mic to assign to which instrument.
Microphone type must also be taken into account. Condenser mics are usually more sensitive and capture more detail, but they also pick up more room sound. Dynamics, on the other hand, typically provide better off-axis rejection, and thus are desirable when you need tighter, more focused sounds. Either type of transducer can usually be made to work, though — what matters more is how you position the mic.
The basic strategy for minimizing bleed using directional mics is to set up each mic so it “hears” primarily one instrument and its rejection zone is “aimed” at any other miked instruments in the same space (see Fig. 2). Note, too, that, in general, the closer the mic is to the source, the less it will hear the rest of the space. Then again, when using directional mics, bass boosting from the proximity effect must also be taken into account — some instruments can sound boomy, bass heavy, or otherwise unnatural when miked too close. Hence the “considerable skill” I mentioned in my opening paragraph — balancing all of these sometimes-divergent, sometimes-convergent elements is not something that can be learned in a fortnight.
Finally, keep in mind that mic bleed isn't necessarily a bad thing. In fact, it can sometimes contribute positively to a sense of space and thus realism in a recording.
Cressman observes that many Latin-music producers tend to push for a hyped high end, making the mix brighter and brighter with each added instrument. He advises recognizing the frequency emphasis of each element and working to put everything together so the instruments don't compete for the same frequency strata. In short, make sure everything has its own place in the mix. EQ applied during mixdown can help, but be careful to differentiate between EQ and level problems — an instrument can sound too bright and cutting simply because it is too loud in the mix.
No matter what precautions you take, any time you use multiple mics on a sound source or group of sources, some phase problems are likely to sneak in. The three-to-one rule, which states that the distance between two mics should be at least three times the mic-to-source distance, is always good to keep in mind when positioning multiple mics (for more information, see “Recording Musician: Avoiding Phase Cancellation” in the July 1997 EM). However, some percussion setups are so tightly arranged that it can be difficult to follow that rule.
Theakston has a remedy for hard-to-avoid phase problems: EQ. For example, try rolling off the highs on a mic that's capturing primarily low-end sounds and cutting the lows on a mic set to pick up higher-frequency information. “That will help clean up any phase mess that happens in the overlapping frequency bands,” explains Theakston, “making the signals much easier to manage in the final mix.”
COMPRESSED FOR TIME
Compression is handy for bringing sound sources forward. However, some engineers, such as Cressman, prefer not to compress while tracking because the effects are irreversible once the tracks are laid down. Others will track with gentle compression to help elements stand out. “You're essentially creating focus, as you would with a camera,” explains Theakston. “That can be especially helpful for featured instruments such as congas and timbales.”
Theakston recommends starting with a ratio of 2:1 or 3:1 and setting attack time at roughly 30 milliseconds and release time at 200 milliseconds. Work a bit with the settings until you get approximately 3 dB of compression. But don't set the attack too fast — on percussion instruments, the leading-edge transient needs to get through or else the sound won't be natural. To increase sustain and resonance of, say, a conga, try lengthening the release time to somewhere between 200 milliseconds and 1 second and then adjusting the makeup gain until you get the desired result. For ancillary percussion — shakers and the like — you can usually get away with simply setting a good level to tape and foregoing compression.
When recording a Latin-percussion ensemble, the priorities are usually timbales and congas. Be sure to get as clean a track as possible for these lead instruments, either by providing some isolation with gobos or by putting the players in separate rooms.
If you're recording the whole group in the same room, use directional mics as previously described, letting room dynamics and proximity of other musicians determine optimal setup. On the other hand, if you're overdubbing one instrument at a time, try changing the distance between mic(s) and source for each track. That technique can add a nice sense of spatial dimension when the tracks are mixed together. Another way to enhance the realism of separately overdubbed tracks is to use a distant or ambient mic in addition to the closer mic(s) trained on the instrument(s).
Now let's look at techniques and mic choices specific to recording common Latin-percussion instruments. I'll start with the “lead” instruments and work outward to more peripheral ones.
Typically a set of timbales consists of two single-headed drums, a woodblock, and two cowbells (one “mambo” and one “cha-cha”) mounted between the drums, and a cymbal off to the side. The overall sound is bright, loud, and very cutting.
Timbales can be miked effectively a number of ways. Theakston likes to go for a tightly focused sound by close-miking the drums with dynamics and positioning an overhead condenser or two to pick up the bell/block cluster and the cymbal. On the drums he generally uses Sennheiser MD 421s placed three or four inches from each drum and angled toward the head (see Fig. 3). He positions a small-diaphragm condenser (such as an Audio-Technica AT4051, Neumann KM 184, or Shure SM81) six inches to a foot above the bell/block cluster. That mic will often pick up the cymbal just fine; if it doesn't, position a second small-diaphragm condenser to pick up the cymbal. Theakston recommends using a highpass filter to roll off the low end on the condenser mic(s) so the low-midrange frequency content from the drums won't be in phase competition with the bells, block, and cymbal.
Cressman usually takes a similar approach, but with condensers on the drums rather than dynamics. The two condenser mics — he favors Neumann KM 84s for this application, but similar small-diaphragm condensers will also work — are positioned further back, about a foot away from the outside of the two drums, and angled down slightly (about ten degrees in relation to the plane of the drumheads) toward the heads. These two mics capture a good balance of drum tone and cascara part (the characteristic rhythm played on the shell of the small timbale), while the overhead small-diaphragm condenser(s) pick up the bell/block cluster and cymbal.
Stereo-miking can yield excellent results on timbales, too, especially if the timbales are well isolated from the other instruments or are being overdubbed individually. Cressman recommends using a stereo mic, such as the Shure VP88 (a mid-side, self-matrixing transducer), or a near-coincident or coincident pair of condensers positioned overhead. For the latter setup, AKG 451s will yield a bright, crisp sound; for a darker sound, try Shure KSM32s. Place the mic pair about 18 inches to two feet above the bell/block cluster. If the mics are positioned too close to the drums, you'll pick up too much cowbell sound, so work with the distance until the levels of the bells and drums are in balance.
“This approach gives you a full, honest, phase-accurate picture of the instrument along with some natural room sound,” says Cressman. “The beauty of it is that you don't have to handcraft the overall sound of the instrument later — which is what you end up having to do if you mic each element separately.”
Another effective way to record timbales in stereo is with a spaced pair of condensers. Place the mics at overhead height, about two feet in front and three feet apart as a starting point, and play with the positioning and pickup patterns to get the best sound. A cardioid pattern will give you a tighter sound, whereas an omni or figure-8 will capture more room reflections and diffusion, resulting in a more live sound. Cressman has had success with a spaced pair of omnidirectional Neumann KM 183s positioned about three feet apart and 12 to 18 inches from the front of each drum. You can also get great results with large-diaphragm condensers (for example, Shure KSM32s, Neumann U 87s, or AKG C 414 B-ULSs).
Of course, timbales don't have to be stereo-miked — you can also get great results from a single well-positioned microphone. Given that musical styles featuring timbales (salsa, son, timba, and others) often involve a dozen or more instruments, making for rather busy mixes, you may find that a mono image will suffice. Position a quality large-diaphragm condenser, such as a Neumann U 87, in front and above, pointing down at the timbales. Cardioid is the appropriate pattern if you need rear rejection, but if not, be sure to audition the figure-8 and omni patterns as well — the additional room sound can be enticing. For a different, somewhat more vintage sound, try a ribbon mic — I've gotten great results using a Coles 4038.
Congas are single-headed hand drums commonly played in sets of two or three. Directional dynamic mics are commonly used for their superior off-axis rejection but are favored also for their tonal characteristics. The old standby Shure SM57, for example, has a meaty midrange that adds oomph and a presence peak that enhances slaps and pops. Another popular choice is the Sennheiser MD 421. Position the mic three to four inches from the head, angled toward the center of the skin so as to pick up both the drum's fundamental tone and hand and finger articulations.
If the conguero (the conga player) is using four or five drums and there's sufficient isolation, mini clip-on condensers such as the Shure Beta 98 or Audix Micro-D can reduce mic-stand clutter and provide a crisp, detailed sound. “The challenge when miking a multiconga setup is getting all the tones to speak evenly,” says Cressman. “If you're getting too much bleed from adjacent drums, you may need to use some EQ to tone down the fundamental tone of an off-axis drum.”
If bleed isn't a problem, small-diaphragm cardioid condensers such as Neumann KM 184s, Audio-Technica AT4051s, and Oktava MC012s are excellent choices for miking congas. For an even more natural sound — one without boosted lows from the proximity effect — use a small-diaphragm omni such as the Neumann KM 183.
To increase low-end punch and resonance, position a floor mic beneath the drum (in addition to the close mic on the head). If the conguero is seated and has the drums resting on the floor and tilted back (a standard position), place a large-diaphragm condenser six inches to a foot away and aimed toward the section of floor beneath the drum. This will catch the lows from the drum cavity reflecting off the floor. Theakston likes using a darker-sounding condenser such as Shure's KSM32 for this application. He advises rolling off the top end above 4 kHz to reduce overlapping frequencies and any phase problems between the top and bottom mics. (You should also try reversing polarity on one of the two mics and listening to the results.)
If the congas are stand mounted, try placing a dynamic mic — the MD 421 is a good choice — three or four inches beneath the drum, aimed up inside the cavity. Reverse the polarity on this bottom mic and audition the combined sound — it will likely be better, as the two mics on the drum are aimed more or less toward one another. To increase low-frequency sustain, add some gentle compression on the low mic.
The bongos consist of two small hand drums, the embra (large) and macho (small). The pair is typically played either suspended between the knees or supported on a stand. Often, a single mic, either a dynamic or a small-diaphragm condenser, is sufficient to capture both drums. Place the mic about four or so inches above and between the drums, positioned to capture a balance of the macho and the embra. “There's a certain amount of depth on the embra side that you want to make sure to capture,” says Cressman. “Balance that strong fundamental with the slap on the macho side, making sure that the slap has a good tone also.”
If you're doing an overdub session and want a brighter, more sparkly bongo sound, record in a live-sounding room to take advantage of room reflections. Theakston generally reaches for an SM57 or KM 184. To increase ambience, he recommends using a large-diaphragm condenser, such as a Neumann TLM 103, positioned about six inches back from the heads.
Despite its simple appearance, the shekere — essentially a hollow gourd enveloped in a beaded net — is a sonically complex instrument. A deep tone emanates from the mouth of the gourd, the net rattles against the sides of the instrument, and the player's fingers tap the base of the gourd, making for three ranges of timbres.
To capture a blend of these sounds with a single mic, Cressman suggests using a condenser — large- or small-diaphragm — positioned at about shoulder height and a foot or so in front of the player. However, if the shekere is to be prominently featured in the mix, you may desire more individual control of the low and high sounds. Use two mics in that case: a large-diaphragm condenser on one end, positioned to capture the low note from the gourd's mouth, and a small-diaphragm condenser on the other end, aimed to pick up the finger taps and bead slaps (see Fig. 4). Be sure to experiment with reversing the polarity on one of the mics so you can determine what arrangement yields the best sound.
Latin-style cowbell patterns project both a high-frequency transient from the closed end of the bell and a lower, more open (though still muted) tone from the mouth of the bell. The high part usually cuts well through a mix, but the fundamental can get lost. The SM57 and MD 421 are again good candidates — either can readily handle the SPLs, and their focused directionality can help to tighten up the sound.
Among condensers, Theakston favors the KSM32, again for its characteristic darker tone. But as Cressman points out, “pretty much any mic can work, as long as you position it well.” Indeed, he once, by necessity, used an AKG D112 (commonly regarded as a kick-drum mic) for this application — and it worked well on the low bell he was recording, thanks to the mic's abundant lows and high-end presence boost.
In general, though, Cressman prefers miking cowbell with a small-diaphragm condenser, such as an Oktava MC012 or a Neumann KM 84. He recommends placing the mic approximately a foot in front of the player, positioned slightly below the mouth of the bell and angled upward (see Fig. 5). That puts the back part of the bell farther away from the mic, which helps to balance the disparate levels of the two tones. “The idea is to make sure you get enough of the fundamental note and not too much high-end clank,” explains Cressman. Remember, too, that players tend to move around when they play, so make sure the microphone is far enough back that they're not moving off-mic.
Claves are loud! Theakston often overdubs the clave track to ensure that the sound doesn't bleed into other mics. But keep the aesthetic of the musical piece in mind. If you want a tighter sound, control room reflections by baffling off the area where the claves are being played. If you're going for a more open, Buena Vista Social Club kind of vibe, then let in the reflections.
Though many different mics will work for claves, Theakston recommends using a cardioid condenser, either large- or small-diaphragm. In a pinch, an SM57 will also work. Both Theakston and Cressman advise against limiting because claves are all about that transient attack. Find a level that works without overloading and track the instrument straight.
Other idiophones found in Latin-music ensembles include guiro, maracas, cabasa, shakers, and triangle. If the percussionist is playing these instruments in a room with other musicians, Theakston and Cressman recommend miking with a small-diaphragm condenser, because those are more focused than large-diaphragm condensers. In general, position the mic a foot or so away from the player to allow for a fairly broad pickup zone — you don't want to limit the percussionist's range of movement.
With overdubs for maracas, cabasa, guiro, or shaker, avoid miking the instrument too closely — some air around the sound is usually a good thing. Theakston recommends setting up a stereo coincident pair of large-diaphragm condensers (or a dedicated stereo mic) about two to three feet in front of the player in a good-sounding, fairly live room. That way you capture a nice balance of the direct instrument sound and some room sound.
Karen Stackpoleis a recording engineer and percussionist who teaches Sound Arts at Ex'pression Center for New Media. Muchas gracias to Jeff Cressman and Scott Theakston.