Loud and Clear: Audio for Experts
By Noah Bolmer
As virtual appearances become the norm, a proper audio-visual systems and technology setup is a necessity for expert witnesses. Once you’re camera ready, it’s time to ensure that you sound as great as you look. In this guide, we take a look at audio equipment, room preparation, and proper mic technique for remote expert engagements.
Microphones
While your laptop, phone, and even webcam typically have a built-in microphone, they are usually not great and can be difficult to position optimally. Microphones ranging from those built into earbuds, to studio grade standalones can fit a variety of needs and budgets.
Wireless Earbuds and Headsets
A cost-conscious option for experts are wireless earbuds with a built-in microphone—which you may already own. While these are designed with mobile devices in mind, they will pair with most computers via Bluetooth or other wireless protocol. They produce passable audio, but they can pick up a lot of background noise, as they are designed to pick up sound that is not directly aimed at them. As with any rechargeable device, the battery degrades over time, and the capacity may not last through an extended deposition. Moreover, wireless devices are prone to dropouts, driver issues, and interference.
If you choose to use wireless earbuds, make sure they are fully charged before your appearance, that they’re paired (some wireless earbuds will only “remember” one paired device), and that they are selected as the audio source in the software you will be using. Choose a high quality pair by a name brand, ensure that the firmware is up-to-date, and conduct a test call prior to your appearance.
Wireless headsets have the same potential downfalls, but typically have a better microphone, which can be placed directly in front of your mouth. While this provides a better audio experience, they can be large and unwieldy, detracting from your professional appearance. Nevertheless, they have become smaller and less invasive, have larger batteries than earbuds, and they will typically live on your desk where they won’t become misplaced.
Wired Earbuds and Headsets
A lower tech solution can eliminate some of the issues inherent in modern wireless audio devices—wired earbuds and headsets eliminate battery, driver (in the case of analogue), and interference issues. They are an inexpensive option with comparable audio quality. Analogue versions which use audio cables (make sure you have a jack) are more reliable than more modern USB versions. Unfortunately, you will have at least one cable to contend with, which can appear messy on camera. If you choose a wired headset or wired earbuds, route the cable such that it doesn’t interfere with your appearance, and don’t forget to remove the device when you stand up or move.
USB Mics
The next step up in audio quality is a standalone USB microphone. These devices are plug-and-play but feature a larger capsule to properly capture your voice, which can give you more presence in remote settings, compared to the relatively tinny audio produced by the tiny microphones in earbuds. Both condenser and dynamic mics are available in USB versions, but for untreated workspaces, dynamics are recommended. They have superior off-axis rejection (meaning they are less prone to picking up ambient noise) and are typically less fragile. A decent USB microphone will cost between $50 to $250 dollars, depending on quality and features.
One drawback to USB microphones is that there is an inherent latency, although this is much more pronounced in older models. Modern versions have minimized this issue, but there can still be some lag before you hear yourself through your own headphones. For this reason, consider a USB microphone with a built-in headphone jack. This allows your voice to bypass the computer, so you don’t hear an echo of yourself a moment after speaking. USB mics with headphone jacks also tend to feature physical dials for headphone volume, microphone gain, and mute, which can be useful during an appearance. It’s always better to have a physical knob than hunting around an application for the right setting while on camera.
As with all USB devices, keep the firmware up-to-date, and test the mic with the software you will be using prior to your appearance with each new version.
XLR Mics and Interfaces
Podcast fans might notice a trend toward studio-style microphones, and it’s for good reason. For the absolute best audio quality, a microphone with an XLR connection paired with a USB audio interface is the top-of-the-line solution. These mics are completely analogue, and have no built-in amplifier or interface, as do USB mics. The advantage is that XLR mics are an extremely mature technology—some of the most popular microphones are unchanged from the 1960s—with countless designs and price points. While they can be expensive, they are designed to be repaired and maintained for life, and used options are readily available at music stores and online auction sites, making these potentially budget-friendly. As with USB options, a dynamic rather than condenser XLR mic is best for untreated, or lightly treated rooms.
Audio interfaces allow you to plug in an XLR microphone into your computer. They feature high quality amplifiers for the microphone and headphones, and tend to have much more robust software than USB microphones. A quality XLR microphone, such as the venerable Shure SM-58 or Sennheiser E845 cost around $100 new, while a studio quality microphone such as the Shure SM-7B or EV RE20 are about $450. A good, basic interface such as a Focusrite Vocaster runs about $100. If you have a well-treated, quiet space and choose a condenser mic, make sure that your interface supports phantom power.
Placement
For general speaking, a dynamic mic’s optimal placement is about six inches from your mouth, with up to a 45 degree off-axis tilt to allow for off-camera placement. Remember, you want to appear professional, so you are better off increasing the gain to keep your microphone off camera, or barely in the shot.
The “microphone polar pattern” refers to the field around the mic which pics up audio most strongly. Most dynamic mic capsules are tuned to a cardioid (heart-shaped) pattern, and if it is selectable, this is what you should choose. It will allow you to make minor head movements while staying audible and rejecting noise from other directions.
To facilitate placement, consider a desk-mounted mic boom. These allow precise adjustments and far better placement than stands. Even USB mics which have stands attached typically have a boom-mounted option. It is crucial to identify whether your microphone is “top address” where you speak into the tip, or “side address” where you speak into the broad edge. In most cases, dynamic mics are top address while condenser mics are side address, so make sure you set your mic up appropriately, as it is not always immediately apparent.
Headphones
For expert witness appearances, avoid using speakers when possible. They can contribute to an echo effect, where your microphone pics up audio from the speakers, and sends it to all participants. If you are using earbuds or a headset, this is a moot point, but if you’re using a standalone microphone, you’ll want a comfortable pair of headphones. These should be wired, so that they can connect to either the USB mic directly, or your audio interface if you use an XLR mic.
Headphones feature open- or closed-back designs, and on- or over-ear designs. Open-back headphones allow you to hear your own voice clearly, which many users prefer. This prevents a closed-in, detached feeling. On the other hand, closed-back headphones better isolate the user from outside noise, giving you a more clear idea of what everyone else is hearing. On-ear headphones are typically smaller and lighter, while over-ear designs usually weigh more, but may be more comfortable, as they do not press down on the ears.
Wired earbuds (also known as in-ear monitors, or IEM’s) are another viable option with great sound quality, if you prefer a more subtle look. These may not be as comfortable over long periods of time without expensive custom IEM sleeves made from ear impressions.
Room Treatment
Expert witnesses should choose a space that is quiet. An interior room or basement without windows is ideal, but choose whichever space has the least ambient and outside noise. Treating a room for audio can be quite expensive, so unless a large part of your career requires high-quality remote audio, it is best to simply use a dynamic microphone, with the gain set just high enough to pick your voice up clearly.
It is possible to dampen reverb and echo with a mic enclosure such as the Kaotica Eyeball or with acoustic panels—but this will not attenuate loud ambient noise from cars, thunder, or loud footsteps from above.
Audio Settings
Adjust gain separately from volume. Microphone gain refers to its amplification or sensitivity to picking up sound, while audio volume is how loud that signal is passed to the output. Gain is typically accessed with a physical knob on USB microphones and interfaces, while other types of microphones’ gain are set using your computer’s audio settings. The gain setting may be called “input volume” or “recording volume”.
To set your levels, mute or disconnect your microphone and listen to any audio through your PC, to adjust the volume to a normal listening level. Once set, unmute your microphone, and set the gain to where you can hear it clearly, but not so loud that it starts picking up background noise. This is easier to accomplish with headphones which provide good isolation, as it can be difficult to differentiate what you are hearing from the room versus through your headphones. Take a recording and listen to yourself in a quiet spot. Do you hear anything other than your voice? If so, reduce the gain until you only hear yourself. If you are unable to isolate your voice from ambient noise, you may need to move to a quieter workspace, or rely on your telepresence software’s audio features.
Many telepresence apps include audio enhancements, such as noise cancellation. These run the gamut from basic ambient sound removal, to voiceprint AI-assisted noise removal. These can go a long way to improving your audio—particularly if you opt for earbuds with built-in microphones—but be aware: these solutions use bandwidth, memory, and CPU cycles. Toggle these effects to see if they degrade the overall audio or video quality before using them during an appearance, and as always, check with your attorney to make sure that there isn’t a court rule against audio enhancements.
Technique
Exercise good mic technique, regardless of what type of microphone you choose. Try to limit dramatic changes in speaking volume. Moving toward and away from the mic changes not only your audio volume, but the overall timbre. This “proximity effect” can be jarring, so try to remain at a constant distance. Hard plosives—letters like P, T, and K—can create bassy booms and pops. In microphones with lightweight capsules near the tip rather than heavier ones recessed in the body, this is more pronounced. Practice speaking with less emphasis on those letters, or consider a pop screen if your mic is sensitive. Mic-specific pop screens and wind screens are typically available, so check your microphone manufacturer’s website. Similarly, generic pop filters which can be affixed to a desktop boom arm are another option, although they can be quite large.
Stay hydrated to help reduce mouth noises, and mute your mic when you are not in a conversation. Note, this doesn’t mean you should mute every time you stop talking; only when you are not going to be speaking for a while. Control your breathing while speaking to avoid heavy breaths into the mic.
Don’t let poor audio get in the way of a productive remote engagement. Practice speaking and listen to recordings of your voice to make any adjustments prior to your appearance. Keep your drivers and firmware up to date. With a quiet room, quality gear, and proper technique, the content of your expert opinion will come through loud and clear!
For over 30 years, Round Table Group has been connecting litigators with skilled and qualified expert witnesses. If you are interested in being considered for expert witness opportunities, contact us at 202-908-4500 for more information or sign up now!