Audio: Building an Audio Recording Room

Chuck Peters | September 2012

Clean, clear audio is an essential aspect of any professional production, but many (if not most) videographers underestimate its importance.

While it doesn't seem logical that the ears of your audience would overrule the eyes, it's one of the many mysteries of video production. You can have creative camera work, excellent edits, great graphics and fantastic effects, but if your audio is awful, your viewers will overlook all of your visual victories and remember only your sour soundtrack. In fact, I have found that if you have stellar sound, viewers may well walk away remembering a video as being "good" even if the graphics, lighting and overall visual quality are nothing more than mediocre. While I don't know that there is a satisfactory scientific explanation for the phenomenon, in my experience this principle holds absolutely true. And as a result, we have to change what we do. If you want to exponentially improve the perceived quality of your videos, one of the simplest things you can do is to invest extra effort into improving your audio.

A good soundtrack is made up of a variety of sources. These often include, but aren't limited to: music, sound effects, natural ambient sound recorded in a environment, voice-over narration (VO), and "sync" sound (audio recording of talent that's seen on screen). Music and sound effects typically come from high quality recordings created by professional content providers. It's the audio that we record ourselves that tends to mess up the mix with problems ranging from background bleed due to lawn mowers, sirens and periodically passing express trains, to thin, tinny, hissy, hummy, or echo-y audio plagued by reflections and reverberations that drown out the speaker's voice and distract the viewer. It's this self-acquired audio that we will focus on here.

When it comes to recording audio. a lot of producers prefer to work in professional recording studios, but you don't have to rent a space or break the bank to record sound that sounds superb. With a small amount of effort and a little creativity you can create an area of your own for recording audio for video. The best way to do this is to pre-proof a place in your own space and record as much audio as possible within the confines of your audio optimized area. It's important to note that not all spaces are equally effective for recording awesome audio. There are a few things you need to keep in mind as you seek to set up a sweet audio suite.

Pick a Space

The space you choose to use as your audio production studio doesn't have to be large or fancy. The primary goal is to isolate your microphones from any and all unwanted sound, so the room should have a door you can close. It won't hurt to have a window in the door since either of you will at some point need to communicate through the door, but you don't want a broken barrier from someone peaking their head because they're curious. The sound quality of the room also makes a difference. A "dead" room is better than a "lively" one. A decent litmus test is to clap your hands loudly once or twice in the room and listen for echoes and audio reflections. The sooner you hear silence, the better.

If you are in a home, you have a few options. A living room with thick carpet, cushy couches and dense drapes will tend to be pretty audio-friendly, but a tiled bathroom with lots of flat, solid surfaces will generally not be a good choice. The clothing in a walk-in closet acts as an excellent sound dampener, so additional wall padding may not be necessary. If you need to deaden a lively room you will need to build some sound dampening panels. I recommend a minimum of two or three standalone panels that you can place in a "V" or a triangle around the microphone. In a pinch, heavy duty moving blankets strung between C-stands or suspended between step ladders are better than nothing. Make sure they are hung high enough to create the best possible barrier. No matter how you slice it, the blanket method is not ideal. While blankets do reduce reflections, they are too thin to effectively block most outside sounds. The better bet is to buy or build baffles to block and deaden sound waves. You can buy professionally built panels from audio specialty shops, or you can build your own with materials that are readily available at your favorite neighborhood home improvement hardware store.

Build Some Baffles

If you decide to build your own baffles you can get great results with materials that you can buy at just about any hardware store. It's okay to be creative with the materials you use, and you can construct your panels in whatever dimensions serve you best to suit your particular needs. But once you know what you need to accomplish, it's amazing how many solutions you can find by walking the aisles of a home improvement hardware store. I recently built several baffles for my production studio at work, where we have a dedicated space (a smallish 15x16-foot room in a home) that I have converted to a small green screen insert set. Because we record there often, we needed some permanent sound dampening, as well as supplemental portable baffles that we could set up for recording sessions and then take down to store out of the way of daily traffic. I built my baffles in three sizes (4x8-foot, 2x8-foot, and 2x4-foot). Look for a 1/2-inch x 2-inch x 4-foot acoustic insulation board (stone wool insulation batts) that looks and feels like plywood, but has special sound deadening properties. Using this as a base, use spray glue to adhere 2x4-foot sound insulation panels to the board. Next, I used cheap 1x2-inch boards and some drywall screws to build a simple frame around my panels for added rigidity. Finally, I wrapped my panels with a thick, textured fabric and used a staple gun to secure the skin. The basic notion here is to create a thick, multi-layered panel that catches and kills rogue sound waves.

In my space, I hung several of the 2x4-foot panels in a pattern on the wall behind the camera, suspended some of my 2x8-foot panels from the ceiling beams using eye hooks and some chain, and positioned my large 4x8-foot panels on the sides of the set just out of the frame. My large panels are connected with door hinges so they can be angled to stand without additional support. When it's time to move them or stow them away, you can just pop the pins, or you can just leave them up and use them as glorified, sound absorbing cubicle walls. Your choice.

The panels you build don't need to look exactly like mine. There are plenty of other panel plans available online, or you can go freestyle and invent your own design. You're not going for looks, so don't worry about it appearing odd. The most important thing isn't how they look, it's how well they function. As long as your baffles effectively muffle echoes and fend off unwanted outside noise, they're good.

 Step Away from the Mic

Another important consideration is to put as much distance as possible between your recording gear and your microphone. Whether you will record to a camera or a computer, the recorder needs to be in a separate control room that is isolated from the talent and the mic. Getting your microphone close to the talent helps to take advantage of its off-camera nature. You may have not noticed the hum of your camera or computer, but the microphone will. Any operating noises from your production crew or equipment can be well insolated with separation. This means you'll need to run some cables, long ones, from your mic to your recording gear. Whenever you are running cables, opt to run the shortest length of cable necessary. So if you are only 25 feet away, don't use a 100-foot cable. Remember to never run audio cables parallel with power cables. If you must cross them, do so at 90-degrees to avoid interference.

For the sake of your talent, it's a good idea to loop a long headphone feed out of the recorder so they can hear themselves and listen to playback. For the purpose of direction, its also useful to have a talkback system. This may be looped into their headphones, or to a small speaker in the VO booth. In a pinch you can even use an open cell phone connection for monitoring and talkback. Here again, whatever works, works!

Isolate, Eliminate, Separate

The secret to recording clean, clear audio is to take as much control as possible over the sound quality of the environment in which you record. Isolate, eliminate and separate. Isolate your mic so it hears only the voice of your talent, eliminate outside noises and echoes, and separate your recording gear from your vocal booth. Whether you use your clothes closet or build a permanent sound design studio for voice recording, you will find that you'll get far greater results when you isolate, eliminate and separate.

Chuck Peters is a 3-time Emmy award-winning writer and producer. He is currently VP of Production at KIDMO/Rivet Productions.