Mic Up the Band

Mar 14, 2008 1:32 PM, By Karen Stackpole

           

HOW THE PROS CHOOSE AND PLACE STAGE MICS

Big Bottom

Electric bass. Although it's standard practice to send the bass direct through the P.A., in some circumstances an engineer will also mic the bass cabinet. The mic you choose should capture lots of low end. Large-diaphragm dynamics such as the Electro-Voice RE20, AKG D 112, Audix D4, Shure Beta 52, and Sennheiser E 602 are good choices. Another good choice would be the Sennheiser MD 421.

If the bass cabinet has a mix of 10-inch and 15-inch speakers, you have a couple of options. For more low-end oomph, put a mic on the 15-inch speaker. If you're a funky slap-and-pop bass player, try putting a mic on one of the 10-inchers or on the horn for more high-end definition and better transient response. Keep in mind that the direct injection (DI) box will give you plenty of low-end fundamentals and that extra twang, so a little lower midrange support from a miked cabinet can fill out the sound.

Acoustic upright bass. It is desirable to take a direct signal from an acoustic bass pickup, though most double-bass players (especially jazz cats) wrinkle their noses at DIs because they never sound the way players like them to sound. In such a case, you should also mic the bass. It's prudent to retain the option to use the direct sound, however, because in a loud situation where you may not get enough gain or definition from the mic, you can still boost the level to give the bass presence in the mix.

The output of an acoustic bass is relatively low, so you have to put the mic in as close as possible. Unidirectional mics are prone to proximity effect (a boost in the low frequencies) when placed very close to a sound source, so you may need to roll off some of the lows. Electro-Voice's RE20 has less proximity effect because of its lateral port design, so it's a good choice for avoiding excessive low-end boom. Sennheiser's MD 421, kick-drum microphones such as beyerdynamic's TGX 50, and condensers (in softer volume bands) such as AKG's C 535EB are also fine for bass. Tiny clip-on condensers are quite popular as well, such as Audio-Technica's ATM35, Crown's GLM100 (this is an omnidirectional, but according to Brenkman, it should work because it's in so close to the bass), and Applied Microphone Technology's SB. You can fasten these low-profile microphones to the tailpiece, to an f hole, or to the ridge that's just above the waist of the instrument. Don't clip them on the bridge, however, because that would inhibit vibrations.

You can mic a double bass in a number of ways. Myles Boisen suggests starting with a dynamic mic with good low-frequency response (preferably a large-diaphragm type, like the RE20 or MD 421), or perhaps a large-diaphragm condenser such as the AKG C 414 B-ULS set to hypercardioid. Put the mic in front of the bridge, but not in front of the f hole, where you get low-end buildup. Boisen has also had good experiences with wrapping an MD 421 in a piece of foam and wedging it in the tailpiece of the bass, pointing up at the bridge. This allows the bassist complete freedom of movement while maintaining good isolation.

Another novel approach from Robert Berenson is putting an MD 421 (with a foam windscreen) on a short boom and placing the mic so that the screen is physically touching the side of the bass in the notch at the instrument's waist (see Fig. 2b). Have the player lean the bass against the microphone so that it picks up the instrument's vibrations directly. Though this method won't capture a lot of string or bow noise, it isolates the instrument pretty well from the rest of the band. You could also try simply putting an RE20 slightly below the bridge out of the bow's way, angled up about 45 degrees, and aimed at the area in between the bridge and the f hole (see Fig. 2a).

Tickling the Ivories

Electronic keyboards. Most engineers prefer to get a direct feed on electronic keyboards. If the keyboardist has an amp and prefers that sound, you could mic the cabinet (as you would a guitar amp with a Shure SM57) and combine that sound with the direct signal. Going direct or using a direct box is generally better, because you tend to get a cleaner sound. In the case of a Fender Rhodes suitcase piano, Brenkman recommends going direct and miking the speakers on the piano to represent the Fender Rhodes sound fully. And with Hammond organs, he's had good results miking both sides of the Leslie cabinet, putting a Sennheiser MD 421, a Sennheiser E 602, or an AKG D112 on the bottom and a Shure SM57 or Shure Beta 57 on the top.

Piano. For miking grand pianos, engineers often favor condenser mics such as AKG's large-diaphragm C 414 B-ULS or Neumann's small-diaphragm KM 184 because of their excellent high end and transient response. Ideally, you should use a pair of mics to capture the low and high strings (see Fig. 3a). Place one mic several inches over the bass strings and the other over the high strings, and angle them apart for greater separation. The closer you get to the hammers, the more attack you'll get; the farther away from the hammers, the mellower the tone will be.

If the environment is loud, try securing the mics inside the piano and closing the lid for greater isolation. You can do this using a pair of PZMs such as Crown's PCC160 (a cardioid boundary mic) and taping them to the underside of the lid. Alternatively, Berenson recommends making little slings out of gaffer's tape and attaching two C 414 B-ULSs to the bars under the lid. You could also clamp the mics to the soundboard (using a piece of foam to protect the wood) with LP Claws or similar mic clamps. A single SM58 pointing into one of the soundboard holes will also do the trick if you have only one input and the piano is going through the monitors (see Fig. 3b).

If you're dealing with an upright piano, open the top and place a split pair of microphones inside, aiming slightly toward the hammers to capture both the low and the high keys. Condensers are preferable, but SM57s work quite well, too. You could also mic the piano from the back, taking time to find the sweet spot. Remember to listen - and to think from the mic's perspective. Another option is to take the front off by the player's feet and to mic the strings from that angle (if the player isn't stomping the pedals or the floor too vigorously, that is!).