Welcome to part two of our Inside the GRAMMY Museum blog series with audio engineer David Trau. If you missed part one, check it out here. As the head engineer at the museum’s Clive Davis Theater, David regularly works with legendary performers like Sting, John Legend, Brian Adams, John Prine and more. Due to the small and intimate design of the theater, many of the artists perform with acoustic guitars. But getting a great live acoustic guitar sound can be challenging because of issues like feedback, muddy mixes and low stage volume. We sat down with David to learn how he approaches live acoustic guitar sound for some of the world’s biggest acts.
What’s the first step in getting a great acoustic guitar sound?
First and foremost, I always want to get a direct signal. Even if the guitarist says the direct out on the instrument doesn’t sound very good, I’ll use that signal for the monitors. At the very least, I try and get a direct signal to supplement the signal from the mics.
What’s your go-to mic for acoustics?
We use the AKG C30 pencil condenser mics a lot, especially any time we have a situation where it’s just acoustic, and they don’t want to plug in. It has been really effective and warm.
Do you use multiple mics or just one?
If you see old videos of Bob Dylan performing, they’ll have eight microphones surrounding him—there are more microphones and stands than there are people on stage. I try and make everything as clean and focused as possible, so I try not to use a wall of mics.
Where do you place the mic in relation to the performer?
A lot of it depends on their playing technique—do they stand in one place or move around a lot and away from the microphone? Generally, I’ll get in as close and tight as possible, but still give them some room to move. Especially with condenser mics, distance is my enemy—the farther away the mic, the more gain I have to use. The more gain I use, the more feedback can get introduced. But the most important thing is making sure the artist is comfortable and able to deliver their best performance.
Is there a sweet spot on the guitar that you aim for with the mic?
When it comes to placement on the instrument, I take into account where the monitors are and place the mic so the least amount of sound is getting picked up. From there, I try to point the mic near the 12th fret, angled toward the sound hole at about 45 degrees. If feedback is a problem or the microphone is further away, I’ll lower the mic stand and angle the mic pointing up to direct the phase rejection of the mic toward the monitors.
Do you blend the mic signal with the signal from the DI?
I try and only use the direct signal in the monitors—that eliminates a lot of problems. In the house mix, I’ll often pan them left and right to give the guitar some stereo depth. Sometimes, I’ll get the blend I want and pan it to one side, then send them to a group that I’ll delay a little bit and pan to the other side. It creates kind of a mock doubling effect.
Are there certain frequencies you roll off?
In general, I high and low pass everything, both live and in the studio. My overall approach is to start rolling off the frequencies until I start to hear it affect the sound, and then back it up. If it’s a solo guitar, I want it to sound as full as possible. But once you start mixing it with other instruments, you need to make some decisions based on the function of the guitar within the arrangement. Is it playing big chords, or is it playing tight rhythms or leads? How does it blend with the other instruments? I try to find the space that it fits in sonically and then shrink it down. If you solo it, it might sound a little thin or brittle, but if you’re trying to take up too much sonic space with all of the instruments, the sound gets muddy or cluttered very quickly.
I like to use the round, low mids along with a little upper mids, but I use some compression to tailor that back, so it doesn’t get in the way of the vocals. I also like it to cut through on the very high end, so you can hear the brilliance and shimmer.
Any final advice for fellow sound engineers or artists who perform with acoustics?
Honestly, the biggest tip I can give any band or engineer is this: be as loud as the softest instrument. For example, if you’re playing with an acoustic guitar that doesn’t have a direct signal, the band has to take that into account to ensure there’s room and space to hear it in the mix. If the drummer is out there bashing, it doesn’t matter what you do as an engineer—you’re going to have a terrible time. The more you try and bring out the guitar, the more you’re going to bring out the drums, especially in a tight space. When everyone takes that into account, the show goes a lot smoother.
Stay tuned for part three of Inside the Grammy Museum to discover Trau’s tips and tips for getting a great sound for bass and drums.