Miking Unamplified Instruments Onstage
Larry Cumings is hardly a newcomer to the art of mixing and miking acoustical instruments. This Grammy Award-winning engineer spent nearly a quarter of a century on the road doing FOH with the David Grisman Quintet and has been the audio producer and FOH engineer for the acclaimed Strawberry Music Festival for 30 seasons. Held in a large campground at 4,600 feet, high in California’s Sierra Nevada Mountains just outside of Yosemite National Park, the event takes place during the Memorial Day and Labor Day weekends each year, with the three-day festival offering a non-stop lineup of bluegrass, folk and other styles of acoustic music.
Lately, one of Cuming’s ongoing projects is mixing FOH for Hot Rize, a Colorado-based traditional-yet-progressive bluegrass band named to honor Martha White’s self-rising flour, which was promoted by Flatt & Scruggs in the 1950s and 1960s. We caught up with Cumings just as he was about to set up for the Strawberry Music Festival and chatted about one of his favorite topics — capturing the essence of acoustics instruments.
Having the right mic or technique can help, but it all comes down to the basics. “Everything starts at the source,” Cumings explains. “Working with David Grisman for 24 years, we traveled with Neumann KM 84s [small-diaphragm condensers], yet where any musician decides to attack, that microphone is out of my control. If they’re experienced, they know where to land the microphone position, and people who really know what they’re doing — like David Grisman — will ‘work’ the microphone,” adds Cumings.
Guitar
Probably the most commonly encountered acoustic instrument is guitar and, here again, “it definitely starts with the musicians. Their experience in knowing where the sweet spot is can do a lot of the job for me, but if you have someone who lacks experience, then you have to work with them.”
However common acoustic guitars are onstage, the best miking position isn’t necessarily the obvious place. “You don’t want to have the microphone right in front of the sound hole,” says Cumings. “Try placing it perhaps under the level of the hole — somewhere between the hole and pick guard, and pointing it upwards towards the bridge or the neck works well. Just try to avoid addressing the hole itself — the tone there is not happening and leads to a lot of boominess.”
Interestingly, Cumings’ first choice for a guitar mic isn’t necessarily something esoteric or super-expensive. “For acoustic guitar, I really like the Shure SM81. It has a high pass filter [-6dB @100 Hz or -18dB @ 80 Hz] that I’ll use, but I’ll also use parametric console equalization as well, around 200 Hz at a medium Q, with something like a -4dB cut. I chop a lot of that out, because that’s where you’ll typically get a lot of boom. Guitar is always quite a culprit — you can’t always get enough gain, and it can get boomy, so I use a more radical EQ. It varies somewhat with different instruments, different mics and different players, but that’s a good general rule of thumb.”
Violin
One would think that violin would be difficult to mic but, “actually, it’s not,” says Cumings. “In fact, violin is pretty easy. There are two “f” holes on a violin and, here again, an experienced musician will know where the sweet spot is and usually come up to the microphone being pointed down toward the instrument and play into that sweet spot, which is usually at the “f” hole on the side with the higher strings. But the right spot for any player comes with experimentation. For example, [Hot Rize mandolin/fiddle player] Tim O’Brien focuses the mic on the fingerboard, close to the body, and gets a great sound. For violin, there are a lot of microphones that sound fine — even a simple Shure SM57 — although I’ve used KM 84s and the Audix SCX25. That mic sounds good on a lot of things, including acoustic piano.”
On violin, a touch of EQ can sweeten the pie and open up your mix. “Violin is also something that I also take up to about 80 Hz for a low cut and then — depending on the instrument — I take a cut somewhere around 3K, so it’s not quite as piercing,” Cumings adds. On the other hand, “violas have a more muted tone than violin, and I tend to go more flat with them.”
Flute
“I’ve used a lot of KM 84s on flute with [Grisman flautist] Matt Eakle — he’s a total pro and knows how to work the microphone. You want the mic in that area right next to the flute player’s lips. Besides the sound of the flute, this also gives you the sound of the wind from the player’s mouth, which you want to capture — it’s part of the instrument.”
A little EQ is always part of the equation, and “depending on the instrument and the player, I’ll typically try to roll off some of the low frequencies you don’t want to amplify, like up to 100 cycles on flute — unless I’m miking a bass flute, which I’d leave flat and let those lows come through.”
Banjo
Another surprise comes from banjo miking. “Currently, I’m working with Pete “Dr. Banjo” Wernick and his band Hot Rize,” says Cumings, “and he plays into a SM57 and it sounds fine. Here again, he’s a professional who’s been around for some time, knows what he’s doing, and knows how to work the microphone. Working with people like that can make my job easy.”
Now in the studio, a SM57 is probably not the first choice on banjo, so does the live selection of a 57 have something to do with keeping the instrument from becoming shrill? “Absolutely,” says Cumings, adding the advice of avoiding SM58s in this application. “A SM57 — as opposed to a 58 — is more of a flatter microphone. A 58 has a peak at 3K Hz, and you just don’t want a peak at 3K on a banjo.”
Acoustic Bass
“I like the Audix ADX20i miniature condenser, which I attach onto the instrument’s bridge using its shock-mounted gooseneck clip, which holds the mic into position. I used it on Jim Kerwin’s bass when I was traveling with David Grisman, and it sounds phenomenal, as opposed to going direct. The miked sound is always so much better. Sometimes I might combine the pickup and a microphone — at about 80 percent mic and 20 percent pickup — if I used a pickup at all.
Some Final Words
No matter what kind of acoustical instrument you’re miking, the combination of trying to capture relatively soft sound sources on loud stages can spell trouble for the FOH engineer. “This can result in phase issues between the front of house and monitors, especially when vocals are very loud in the monitors. That vocal sound coming back into an instrument mic can result in a hollow sound — which sometimes can be fixed by reversing the phase on that channel, but sometimes not,” says Cumings.
“If you have the microphone pointing up toward the instrument — as opposed to straight-on — you should have an opportunity for better sound, because the mic is not going to be picking up as much of the monitor reflections. Usually the position going up away from the monitor and towards the instrument works best.”
The best monitor solution in such cases would be using IEMs. “My job at FOH gets a lot easier, without that added issue of monitor reflections bouncing off instruments,” says Cumings. “That makes for a cleaner sound at front of house. The mic selections and EQ choice are about the same, but there’s with less garbage — monitor reflections — coming into the microphone. It can be frustrating to mix with too much monitor reflection, which is something that every front-of-house engineer has experienced.”
