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Bombastic Bass

CRAFTING LOW-END PERFECTION IN YOUR MIX

Spinal Tap’s double entendre to the basement of the audio mix is one of the few pieces of music written and performed by three basses and drum kits. The odd instrumentation is great fodder for comedy, but also points to the fact that one of the most important members of the band, the bass, is most often not afforded “rock star” status. This is unfortunate, because the deep range of the instrument, approximately 41 Hz to 300 Hz, gives it the power to shape our emotions in ways that other instruments simply can’t. Would the menacingly simple two-note Jaws theme — which still elicits fear in the hearts of swimmers — have the same power if played on the piccolo or trumpet? I don’t think so. The sheer size of the bass sound commands the listener’s visceral respect, and the engineer must capture that power. In light of that “big” job, this installment of Mix‘s “Recording the Band” series concentrates on recording the electric, acoustic and upright bass.

Acoustic bass can be miked like an acoustic guitar; here, a Telefunken RFT M16 was used.

photo: Chris Baily

GETTING IT RIGHT FROM THE START
In all of our “Recording the Band” features, the underlying theme is, “get it right before the red light comes on.” Setting up the bass should be the starting point in that process; for simplicity’s sake, here, we’ll focus on electric bass. The good news is that electric bass and guitar share much of the same procedures for setup and tuning: adjusting the truss rod, adjusting the bridge for optimal “action” and tweaking each string so it is perfectly in tune along the entire length of the neck. (A useful guide to electric bass setup can be found at www.weedhopper.org/Bass_Guitar_Setup.asp.) As for upright, although tuning the instrument is straightforward, deeper maintenance is best left to an artisan who specializes in stringed instruments. Like tuning pianos, the process is nothing to be trifled with by mere mortals.

After setting up the bass for optimal player experience, make sure that the strings are new. Newer strings will better exhibit the upper harmonics and sound brighter. Bass strings come in a number of varieties, including round wound, half-wound, round core, hex core, tapered core, stainless steel, nickel and nylon wrapped. A quick trip to www.DRstrings.com will get you up to speed on the latest product trends. Each variety will alter the timbre, giving the player the tonal edge or ability to sit in the mix that they strive for. Knowing the personality of the instrument’s many colors only increases the chances that you, the engineer, will achieve stellar results. Strings for the upright bass range from stock steel or tungsten strings to the more esoteric custom gut strings, some costing more than $100 each. These are chosen according to the player’s preference for a sharper attack with longer sustain or for a more blunt attack with a shorter envelope.

KNOW YOUR INSTRUMENT
Knowing the player’s instrument, style and tone will help you choose the proper mics, DIs and signal chain to accentuate that sound. Mics and contact transducers can add a certain edge and tone that you can’t get through a bass amp or DI alone. For instance, for his CD Soliloquy, bassist Michael Manring’s instrument was recorded using a variety of transducers, including ceramic pickups, to flesh out the tone. (See “Case Study” sidebar, page 42.) Combining a variety of tones from various sources — recorded to their own tracks — gives you a wider sonic palette from which to choose when mixing. For example, a mic placed near the player’s fingers, even on an electric bass, can provide the string noise that is lost through a pickup.

There are a lot of things you can tell from an engineering standpoint just by understanding the instrument. For instance, it goes without saying that the tone of the electric bass relies heavily on the pickups, but do you know how different pickups sound? For example, a stock Fender Jazz bass will have a lot of bottom and top end, but the same bass fitted with EMG pickups will have more midrange presence. Being able to relate to a player on his or her own level gives an engineer a lot of credibility.

Active basses have special electronics issues to consider: An active EQ or preamp makes the instrument’s output hotter than that of a stock bass, greatly affecting tone. Also, a good way to keep your signal clean is to be sure that the battery has been changed prior to the session.

WHY DI?
Recording bass direct gives you the advantage of isolation, letting you place the player anywhere in the studio or control room. However, no two DI boxes are alike, and choosing the right unit for the job is important. The DI’s basic job is to boost the level from a high-impedance instrument level signal down to a low-impedance mic level signal that can then be plugged into a mic preamp. Active DIs are powered through AC, phantom power or a battery; active units are further broken down into tube or transistor types, all of which have their own sets of features and sonic personalities.

On the other hand, passive DIs employ a simpler approach, using a transformer to get the job done. If you’re recording an active bass, some DIs just won’t handle the hot output; knowing the right product to use in this situation can save you a lot of time and headache in a session. (If you have limited resources, then choose a unit with a pad to give you the necessary headroom.) Like microphones, every DI has its own sound, so experimenting with a number of them will fill out your engineering bag of tricks.

A preamp combo unit with built-in DI input (such as the GML 2032 above) can be easily used to record bass direct.

photo: Chris Bailey

At the most basic feature level, you can usually count on a DI having a pad, polarity flip button and a throughput, which allows you to send bass output into an amp. Some active DIs, such as A Designs’ REDDI and Groove Tubes’ Ditto, offer some degree of gain, sometimes allowing you to plug directly into a line-level input. Millennia’s TD-1 is a DI/preamp/EQ/re-amper/splitter in one box. You can also rely on a high-quality mic preamp combo unit that has a DI input — such as the Millennia STT-1, GML 2032 or the Avalon 737 — to get the job done. These all-in-one solutions not only give you a great-sounding way to make the jump to low impedance, but also supply the mic preamp, compressor and an EQ. If you have multiple instrument outputs, multichannel DIs such as Radial Engineering’s JDI Duplex give you two DIs in one box. Radial’s JDI single-channel unit acts as a passive mixer, allowing you to take a stereo input and sum it to a single, low-impedance mono output.

Some preamps and DIs provide variable impedance. Matching the DI’s output impedance can boost level and tone while significantly reducing the noise floor. For example, the Little Labs Multi Z PIP Instrument preamp/DI/re-amper and the new Universal Audio 4110 mic preamps offer some degree of impedance switching with impressive results. Universal Audio preamps have an additional tone-shaping switch, adding even more variations. There are also some good DI/tone shapers for the home recordist, such as the Line 6 Bass POD and Tech 21 Bass Driver DI, both of which are inexpensive and have created a buzz on the home recording sites.

MIKING AN AMP
If you’re recording an amp, you can mike the cabinet in the same way you would a guitar amp. For a comprehensive set of techniques for amp miking, check out “Recording the Band: Guitar Greatness,” in the March 2005 issue of Mix or Mix‘s Seminars on Demand guitar recording tutorial at www.mixonline.com/sod.

When recording an amp, use a good power conditioner such as the Furman AR-1215 power conditioner/regulator to take out any distortion introduced through the power grid, which can have a profound effect on tone. This step is especially important in live situations where the power may be an unknown factor.

ACOUSTIC BASS
Although rarely used outside of “unplugged” live settings or on sessions where its specific tone is sought, the acoustic bass — that is, an acoustic electric bass that resembles a large guitar — is miked quite similar to an acoustic guitar. An X/Y array, single mic or ORTF pair work especially well. Some instrument models have internal electronics and pickups for live “unplugged” use but can sound thin. If you’re recording live or for broadcast use, you can use a mini mic such as the DPA 4061, which comes with a mounting kit that includes sticky pads that can be attached anywhere on the guitar. In addition, the mic is so small, it can be actually mounted inside the instrument. Mixing this signal with the internal pickup can be the ticket to a fuller sound.

UPRIGHT CITIZEN
The upright bass is a beautiful instrument; using some very basic techniques, you can record it just right. Low-frequency energy emanates largely from the bottom of the instrument, so placing a single microphone near the floor not only gets you more low end, but takes advantage of the way the floor boundary naturally accentuates these frequencies. You can also pick up some very nice tones right where the player’s hands pluck the strings. A second mic can be added here, at roughly the same distance from the instrument as the lower mic for phase continuity. The two signals can then be mixed together for the perfect blend of string sound and low end. Ribbon mics are especially good choices for this application, as they have a tendency to round out transients and render a “compressed” sound to the tone. A large-diaphragm condenser mic, such as a Neumann U67 or AKG C12, is a popular choice.

IN THE MIX
During mixing, it’s key to decide the bass’ role in relation to other low-frequency material. In a traditional jazz setting, the bass takes precedence over the kick drum, while kick may be accentuated more in other genres such as rock and pop. Because the bass and kick are usually panned center, placing the track away from other instruments sharing the same bandwidth is not an option, so the volume balance between the competing ingredients must be achieved with the fader or by EQ’ing the specific instruments for the perfect fit.

Allocating the right amount of room for bass in your mix can be tricky. If the bass is by itself or in a more sparse setting, the tone can be larger. If other sustained low-frequency material surrounds it, such as keyboard pads or electric guitars, spectral adjustments will have to be made to keep the mix from becoming a muddy mess. These adjustments are best made through a high-quality EQ or filter.

When mixing in a DAW, high-quality plug-in EQs — such as the MDW 5-band EQ or the URS A Series EQ — are excellent tools for adding bottom to the bass. In addition, Waves’ MaxxBass or RBass subharmonic generating plug-in is a simple and very effective way to help out the low tone of any instrument in need, as are its Q Series EQs.

While plug-ins are easy to use, the hardware side imparts the greatest tonal variations to the low end. Whether it’s the “iron” sound of a transformer or the harmonic distortion added by a real tube, to my ear, hardware is king. The beauty of a Pultec EQP-1A, API 550 or Manley Massive Passive can’t be overstated. This sentiment also goes for compressors. Each LA-2A, Fairchild, Inovonics or 1176 has its own sonic signature, and they are all hard to beat. While the most frustrating thing about the vintage models is that they’re all different, when you find “the one,” it will be a treasure envied by any self-respecting tone-freak. A plug-in version of the same hardware, while consistent and often good enough, will always sound the same, and often “good enough” is just not the same thing.

The question of whether to use compression is one of personal taste. A compressor will provide an evenness of attack and dynamics, along with a change in the color of the instrument. The effect of the compressor is also greatly dependent on the instrument and the player’s technique. So while you may develop a favorite technique, don’t expect it to sound the same in every situation.

There are times when re-amping the bass signal is the best way to help boost the mix’s bottom end. For example, getting bass amp isolation in a room can often be difficult because low frequencies are largely nondirectional. (The last thing you want is a bass amp leaking onto other tracks during a session.) This is where re-amping, using a special box specifically designed to take a low impedance signal back up to instrument level, is a smart decision. Adding the re-amped track later in the mix gives you the best of both worlds, letting you have the isolation of a DI when tracking, along with the added tone of a bass amp. Re-amping boxes from Little Labs, Millennia, Line 6 and Radial Engineering, among others, give you the tools you need to boost your signal impedance back up so you can plug it directly into an amp, which can then be miked and re-recorded or just run live for the mix.

Never dismiss the idea of recording bass as being as simple as plugging it in and hitting the red button. Experimenting with these tools and techniques will show you that bass is as capable, and deserving, of audio finesse as the other bandmembers. I’ll close with the engineer’s prayer: May your bottom always be big and round.

Kevin Becka is Mix’s technical editor.

THE STORY BEHIND THE SOUND
“You’re So Vain” Bass Reborn for Janet Jackson Hit
By Kevin Becka

Engineer David Rideau’s job on Janet Jackson’s Son of a Gun involved some audio super-sleuthing. The song contains parts of Carly Simon’s “You’re So Vain,” including the rumbling signature opening bass line originally played by Klaus Voorman. Producers Jimmy Jam and Terry Lewis gave Rideau the task of nailing the familiar tone for Jackson’s retake. Ace L.A. session bassist Alex Al got the call and showed up at the studio, Record One in Los Angeles, with a bevy of basses and the original CD. “The tone was a muffled style, very similar to the sound that Motown bassist James Jamerson made famous,” says Rideau. “Not only was it difficult to cop the tone, but also the style, but if there was anyone that could do it, it was Alex.”

Al and Rideau auditioned a number of basses, including a 1977 Fender P Bass, a 1968 Fender Jazz bass and the hands-down winner: a 1964 Fender Jazz bass. Rideau ran the bass through a custom passive DI with a Jensen transformer, and then into a Neve 1073 preamp, which ran directly to Pro Tools. Once signal was routed, Al proceeded to try various styles and techniques to capture the elusive tone until he came up with the idea of putting packing foam under the strings. After experimenting with various amounts of foam, they finally nailed it and the rest, as they say, is history. Mystery solved!
Kevin Becka

< Miking solution for upright bass:
Placing a mic near the bottom gives you more low end and takes advantage of the way the floor boundary naturally accentuates these frequencies. A second mic, added where the player’s hands pluck the strings at roughly the same distance from the instrument as the lower mic provides phase continuity, and the two signals can be mixed together for a nice balance of string sound and low end. Here, Telefunken M16 (bottom) and a Studio Electronics SE-3 (upper) were used.

Rick Pekkonen, Tony Levin, Bob Power and Randy Jackson share their tips for recording a great bass sound. Get the lowdown here.

Listen to our “Recording Bass” theme song here.

Click here for a clip of bassist Michael Manrig’s song “Insomnia Lessons,” from his album Soliloquy.

CASE STUDY
Showcasing Solo Bass on Michael Manring’s Soliloquy
By Jeff Forlenza

Bassist Michael Manring recently recorded his CD Soliloquy (www.manthing.com) himself in his home studio in Oakland, Calif. Manring, who studied at Berklee College of Music and the Peabody Conservatory, and has toured as a bass soloist for 20 years, recently had the opportunity to realize his longtime artistic vision: recording a solo bass album.

Manring had very specific ideas about how the solo effort should sound. “Normally with the bass, the sound is a very compact, direct sound,” he says. “That’s fine in a band mix when you only have a little piece of the sonic pie. But with a solo bass recording, you have this huge canvas to fill up and not paint in one corner.”

His studio is equipped with an Alesis ADAT, a Soundcraft mixer and a couple of RØDE microphones. While his recording equipment is basic, the instrument signal path is not. Manring’s bass guitars are custom-designed by Joe Zon in Redwood City, Calif. The Hyperbass (Manring’s signature instrument) has an extended three-octave fingerboard and is proportionally similar to a bass violin. Manring: “The Hyperbass has an output for each string, which allows me to control and balance the sound of each string. There are also transducers built into the body, and these come out as a fifth output.”

Manring plays through a SWR Baby Blue amp, sending the signal directly to the ADAT via different DI boxes for each of the string outputs. He also used two microphones to capture the acoustic aspect of his performance: a RØDE NT1 and NT1000. “Generally, I place them as close as I can without hitting them when I play,” he says. Manring also places ceramic transducers on the bodies of some of his basses, to provide stereo output of the high transients that magnetic transducers don’t pick up.

Being his own recording engineer meant separating the creative performer from the technician. “First, I’d have to set everything up, which is a long process,” Manring explains. “Make sure all the levels are okay, that the mics are placed well and that the strings are new and are going to stay in tune — it takes hours. That process is so counter to the performance process. So I usually set up in the morning and take a break for lunch, and then come back and play.”

For the mix, Manring went to Tony Mills at Spark in Emeryville, Calif., where they mixed the album in Pro Tools. “I was thinking of mixing this album myself in keeping with the soliloquy theme,” Manring says, “but I had mixed my last album [Book of Flames, Alchemy Records] with Tony, and I was really happy with the sound we got.”

Manring and Mills experimented with mix ratios between tracks from open microphones, transducers and direct string inputs for each piece as they mixed. “We started with the direct signal or signals from the strings,” Manring says, “We added everything else around that. Usually, the open mics are the next-to-most important thing. Those add a spatial element. There are slightly different equalization and compression ratios for different strings. Then the effects are added at the last step.”

Manring’s sound fills the mix canvas with broad swaths and sharp staccato notes. “That’s how I hear bass: so full, filling the sonic spectrum,” Manring says. “There are certain sonorities that work on a solo bass that wouldn’t work if you tried to play it on any other instrumentation.”

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