Sound Advice: Mics for All Occasions

Hal Robertson
October 2007

Yesterday, I stopped at a local music store to pick up some supplies for my son. Inside, I was treated to a conversation between the hotshot manager and a microphone shopper. Over the next ten minutes, the manager bombarded this poor customer with every microphone myth and piece of misinformation he could muster. Having spent over 25 years in professional recording and sound, I found it hard to keep my mouth shut, but I managed to remain professional and adult through the ordeal. It made me realize how little people understand about microphone choice and application. So this month, we'll investigate mic selection and how to maximize mics in your productions.

There's no getting around it - there will be people in your videos from time to time, and people tend to talk. That means you'll need to mic them. The trick is getting the best sound while still serving the needs of the production. Interviews and other controlled shoots have a couple of options. First is the trusty lapel microphone. Clipped on or under clothing, this workhorse gathers consistent sound by keeping the mic a constant distance from the talent's mouth. There are a few caveats, though. Lapel mics tend to be omni-directional, picking up sound equally from all directions. This makes it difficult to isolate voices from loud background noise. Also, if you're hiding a lapel mic in clothing, you may pick up rubbing sounds. Try to keep the mic as stationary as possible, using gaffer's tape or other creative fastener. (We've recently found some lightweight medical tape that works pretty well, too.) Failing that, try other locations to minimize the noise.

Another popular choice is the shotgun microphone. These beauties are highly directional and perfect for picking a voice out of a crowd or isolating it from other noises. Usually, you attach shotgun mics to a boom pole or microphone stand, although you can hold them too. Due to their increased sensitivity, shotguns can pick up quite a bit of mechanical noise, so you usually want to install them in a shock-absorbing mount. In use, you typically suspend a shotgun directly over and just in front of the subject. Be careful to keep the mic out of your shot framing. More than one movie has made it to screen with telltale mic hardware in the shot. If the overhead option doesn't work for your project, try a lower position, with the mic pointing up at the talent. The sound is almost as good, and the lower position offers some flexibility in certain situations. If you're shooting outdoors, don't forget to use a serious windscreen. Rycote, Windtech and others offer complete solutions for anything from a breeze to a hurricane.

Eventually, you'll need to record something like a band, orchestra or choir concert. This requires a different discipline and occasionally some political skill. Although you could use the stereo mic on your camera, the best way to get a solid recording in these situations is with a stereo pair of external microphones closer to the action. The July 2000 issue of Videomaker has a more detailed article on stereo miking, but we've got room here to cover the basics. Start with a pair of identical microphones and a tall mic or light stand. Using a T-bar or some creative clamping hardware (or even two stands), mount the microphones so that the business ends overlap in a 90-degree pattern. With the microphones on top of the stand, position the setup at least 10 feet over the stage area and a few feet away from the stage, pointed toward the musicians. A closer location will produce a tighter recording, while a more distant location will add some more room ambiance. Alternatively, several manufacturers make single-point stereo microphones that are much easier to set up and offer a smaller visual signature. They are perhaps a little too expensive for the casual user, but they're worth investigating if you do this type of shoot regularly. Whatever the mic choice, you'll need some long mic cables running back to the camera. Depending on your gear, you can blend the microphones with a mixer first or just plug them in directly. Due to the location and quality of the mics, your recording will have clarity and depth most amateur shooters could only dream of.

Now for the politics. Some may view your mics and stand as a visual distraction, and you'll likely need to get permission to set up. To overcome any resistance, offer the musical director a copy of the finished video. Depending on the content, you may even be able to offer finished videos as a fundraiser for the music or theater program. This could open doors to a side business you never even considered.

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