Monitoring in Noisy Environments
You’ve probably never given a thought about how to monitor in a noisy environment until you’ve recorded something at a concert or on a street, then listened back to the results in utter shock. Working in film and television, I’ve encountered instances where an important interview was smothered in noise, heavily distorted, or barely audible. Audio experts like us get called in to remedy the situation, but there’s often very little that can be done except to make the artifacts less apparent. The good news is that much of this can be corrected on location and in real time with a few simple techniques.
Monitor at All Times
In an audio or video recording process, at least one person should be listening to the audio feed at all times. This step might seem obvious, but it’s non-negotiable. The person listening might include the show host, performer, sound tech, or production assistant. Ideally, the person(s) monitoring have been trained in what to listen for, and know when the audio requires attention. As simple and monotonous this task might sound, we don’t recommend passing off such an important duty to your newest intern. The consequences of a ruined audio recording can be severe, if not demoralizing, and aren’t worth your reputation or your job.
Stop Recording If Necessary
If working with a crew, give the person monitoring the audio feed full permission to halt the recording if needed. I’ve worked with naturally shy videographers, sound techs, and (especially) interns who feel intimidated by performers, celebrities, directors, and producers. The person in charge of your audio feed must feel confident in taking charge, and interrupting the recording if problems arise. Nobody wants to be interrupted in the flow of a performance or conversation, but the alternative is ending with far more wasted time, energy, and money.
Use Closed-Back Headphones or In-Ear Headphones
Closed-back headphones were designed for stage use and studio recordings, where ambient sound pressure levels often meet or exceed 120 dB. Unlike open-eared headphones or earbuds, closed-back headphones completely cover the ear, offering to some separation between the listener’s audio feed and ambient sounds. Common closed-back headphones like the Audio Technica ATH-M50x‘s provide enough outside attenuation for most situations without the need for noise-cancellation technology. Closed-back headphones also keep the headphone feed from leaking into the microphone, reducing the risk of artifacts from headphone feedback.
If closed-back headphones create discomfort or pose problems with visual aesthetics on camera, opt for in-ear headphones that lodge inside of the listener’s ear canal. This also helps isolate the listener’s feed from the ambient environment and can be concealed more easily than over-the-ear headphones. For professionals, consider using monitors made from custom ear molds for better comfort and concealment. Like closed-back headphones, in-ear headphones also help keep the headphone feed from leaking into the microphone, reducing feedback artifacts as a result.
Monitor Above the Noise
This is a powerful, yet unintuitive trick used by audio professionals in any recording environment. Since even the closed-back headphones allow some ambient noise to pass through to the listener, it’s important to “overpower” these with the monitor feed. Turn the headphone gain up on your recording device or camera until extraneous sounds are virtually inaudible, and you can hear the direct headphone feed almost exclusively. If recording in an especially loud environment, use this trick to briefly check for problems with the recording, then lower the gain to minimize any potential long-term hearing damage.
Side Note: Listen Safely
While it may be important to monitor at loud levels for occasionally, never do this for an extended period. Most hearing damage is permanent. Be vigilant about protecting your hearing, and remove yourself from unreasonably loud environments. No job is worth permanent hearing damage and most governments (OSHA in the USA) provide legal workplace protection with regard to hearing safety. For more information about safe listening levels, read this free booklet from the World Health Organization (WHO).
Use Meters as The Last Resort
There might be instances where listening to the audio feed is either impossible or impractical. If you’re recording a travel vlog alone, for example, wearing in-ear headphones might not match the aesthetic. If you have no other option, make sure that you have some visible indicator of your audio levels at all times. This still won’t tell you if your microphone is distorted from wind, or drowned out from a passing car, but at least you can make sure that audio isn’t getting distorted from recording too loudly. We recommend it only as a last resort due to its unpredictability, but it’s far better than nothing at all.
We feel that Moore’s Law applies to audio production more than any other field, and it pays to monitor audio vigilantly, especially in noisy environments. Listen constantly, use proper headphones, listen loudly (but safely), and ditch headphones for meters as a last resort. We hope that you can put these techniques to use in any environment, whether you record videos outdoors, record music at concerts, or perform live on stage. Don’t wait until that critical interview, shoot, or performance to begin incorporating these techniques into your workflow.
Have you found any helpful tricks to monitor in audio in noisy or challenging? Let us know in the comments below.
Photo credit: Eryk Thompson