Every videomaker has a pet peeve, a standard
they don’t like compromised in any project. Some shriek upon sight of shaky camerawork. Others jump at
a jump cut, or squint and shout at bad lighting. Personally, I cover my ears at the sound of poorly recorded
audio.

Bad audio aggravates me because it aggravates the audience. If your audience has to work to just
hear the story, they’ll find it harder to enjoy your work.

Bad audio is especially inexcusable because it’s so easy to prevent. To catch most any audio
problem before it catches you, all you have to do is wear a set of headphones.

So why don’t more videomakers wear them? I don’t have any concrete evidence, but I think
we’ve developed bad habits that draw our attention away from getting good sound.

In an effort to rid the world of poorly recorded audio tracks, I offer this refresher course on how to
ensure great sound by properly using a set of headphones.

Class in Session

Lesson one: keep the headphones in your camera bag. Don’t carry them in a light kit, grip bag or briefcase.
A rule this simple may insult your videomaking expertise, but it’s here for a reason.

With headphones in the camera bag, you eliminate the most common excuse for not wearing
them: "I forgot to bring them." No matter how quickly you gather the gear, how many bags you bring, or
which ones you decide to leave at home, you’ll always have headphones with you on shoot days.

Keep a stash of adapters in the camera bag, too. They keep you plugged into camcorders, decks
and mixers, regardless of type or location. The most common jacks and plugs are 1/8-inch and 1/4-inch
phone plugs. Local electronics stores like Radio Shack stock these adapters, so there’s no excuse not to
have them around.

Lesson two: make it a habit to monitor audio every time you shoot, even if what you record will
never end up in the final cut. Make sure someone is wearing phones and listening carefully whenever you
roll tape.

Don’t let a lazy videomaker tell you this wastes time and effort. It forms a habit that may keep you
from either forgetting to bring headphones or deciding not to wear them. If you botch the audio, bringing
the cast and crew back a second time is much more expensive than wearing headphones the first time.

Lesson three: always monitor audio from the camera or deck, not from a mixer.

An example might be where three mikes send signals into a portable mixer, and the mixer output
feeds your camcorder’s audio inputs. If you plug headphones into the mixer headphone out, you’ll hear
how the mikes blend into one signal.

However, you won’t hear how your camcorder reacts to that signal. Its level may be set too high
or too low to record good sound. Worse yet, you may have a bad cable between mixer and camcorder. You
won’t know unless you monitor at the camera or VCR headphone jack.

Silence versus Ambience

Lesson four: listen to the silence as carefully as you listen to the sound. What seems like silence to an
untrained ear is actually a blend of many low-level sounds. In audio terms, we call it ambient sound, or
ambience.

For example, nearly every office building has an air conditioning system that runs all day long. If
you spend much time in these places, your ears "tune out" the AC whir. Microphones, however, don’t filter
out anything. The only way to hear how that AC noise affects your audio is to listen carefully through a set
of headphones.

Once you train your ears, you’ll hear things like AC or other ambient noise when you walk into a
room. That will make you a better location scouter, and as well as a more proficient audio engineer.

Lesson five: break the habit of just watching the meters. Despite being designed to report signal
level, some meters aren’t sensitive enough to reveal audio problems. For example, sudden spikes like door
slams, gun shots or vocal popping can distort the audio on tape without causing the meters to flinch.

Besides peak distortion, meters don’t reveal annoying ambient sounds or poor tonal quality, which
inevitably do the most damage to clarity and presence in your audio.

Also, don’t trust the automatic gain or audio limiter. Feel free to use it; most of the time a limiter
works well. Just don’t switch it on and forget to listen. It may induce "pumping" or "breathing" as it tries
to compensate for extreme changes in signal level.

Also, if the sound is too low, a limiter will increase it. While this might make quiet voices easier
to hear, it may also raise ambient noise from a whisper to a roar. If your camcorder allows you to defeat its
auto gain control, try shooting without it.

Recognizing Distortion

Lesson six: learn to recognize and correct audio "red flags" like clipping, popping and rumble. Pros who
earn their keep managing audio learn to prevent these problems before they start. You may need a little
practice to become proficient at this.

Set up a practice interview with a friend or crew member. Put your mikes and headphones through
some simple tests to hear how they react to different situations. In these exercises, be sure to use the same
mikes and headphones you’ll use in the field.

Ask your mock interviewee to read some text aloud while you adjust input level and mike
position. Make one adjustment at a time. Listen carefully to how the voice quality changes after each
change.

Clipping occurs when peaks in an audio signal exceed the camcorder’s ability to record it. Instead
of passing the excessive level, input circuits "clip" the sound wave off at its loudest points. This turns the
normally smooth curves of a sound wave into a series of flat shelves. To your ears, severe clipping turns
everything into the grating rasp of a chainsaw.

Teach yourself what clipping sounds like by deliberately overloading the audio circuits. If your
camcorder has an input level control, gradually increase the level until you start to hear a buzzing or raspy
sound on the louder parts of their speech. That’s clipping.

Now ask your subject to vary the intensity of their speech as they read, loud on some parts, soft on
others. As they do, gradually adjust the level and listen carefully to how clipping changes. At some
settings, you may not hear clipping during the quiet parts, but you do on words and phrases they
emphasize.

This difference is something many videomakers miss in monitoring their audio. They adjust levels
during set-up, and don’t bother to listen while the interview takes place. As the interviewee raises his or her
voice to make a point, they sometimes send meters and distortion levels into the red.

When recording, you want a level that won’t induce any clipping, no matter how loud it may
get.

Popping describes what happens when a short, strong blast of air directly hits the mike pickup. To
your ears, popping sounds like loud thumping or buffeting.

In interviews, listen carefully to words like "participate," "person" or any words with strong
"plosive" consonants. You’ll hear popping if the subject is too close to a microphone, especially if it’s
directly in line with their mouth.

Of the three audio red flags, rumble is the most difficult to hear. Rumble describes low-frequency
sounds most often associated with wind noise. Our ears normally tune out wind noise, which can make it
hard to hear unless you’re listening for it.

Even slight breezes can cause rumble problems on an audio track. While wind is the most
common culprit, rustling fabrics can also cause rumble, particularly with a lavalier mike.

To make things more difficult, some headphones may not have a frequency range low enough to
hear rumble without really cranking up the volume. Also, some of the open-ear headphones, which don’t
provide insulation around the ear, may allow other sounds to mask the rumble.

What you may not hear in your headphones, you might be able to see on audio meters. The low-
end waves associated with rumble cause meters to move dramatically. If you hear something that sounds
like wind noise in your headset, check the meters.

Mono is Better

Lesson seven: unless you’re specifically recording a scene in stereo, it’s easier to monitor audio in
mono. Most camcorders have stereo headphone jacks, with the left and right channels separated. This
makes monitoring a two-mike interview difficult, because you don’t hear sound in both ears. It’s easier to
hear level and tonal differences when the signals are fed to both ears.

Some camcorders have switches to control audio monitoring. Switch to the "mono" or "mix"
position. If yours doesn’t, plan a trip to Radio Shack to pick up the appropriate adapters.

Lesson eight: choose the right headphones for your type of work. You can choose from over-the-
ear, earbud, or foam-padded styles.

Over-the-ear headphones provide the best performance, but cost the most. They feature a soft,
padded shell that surrounds your ear and seals out much of the sound around you. They give you the most
accurate representation of what will end up on tape. They’re the only choice if you shoot in loud
situations.

Many videomakers get by with either earbud or soft-foam headsets, similar to those sold with
personal stereos. The earbud styles actually fit inside your ear; the soft foam sets rest outside the ear.

They don’t cost much, usually less than half the price of a good over-the-ear set. They also don’t
weigh as much. For most uses, these headsets do a good job of reporting what you’ll get on tape.

The disadvantage to these lighter headphones is that they won’t seal out surrounding sounds as
well as an over-the-ear set. Unlike the over-the-ear sets, also called closed-ear sets, earbud and foam-
padded headphones have an open-ear design.

The sound of someone talking or moving a piece of equipment may interfere with the sound in
your headphones. You may find yourself asking which sounds are coming from the headphones and which
are coming from outside them. It’s even more difficult if you’re shooting in loud situations.

Also, some of the lightweight models can get uncomfortable after a few hours.

The best advice is to survey the types of projects you do, and then buy accordingly.

Lesson nine: be cautious of high volume levels.

Although headphones look tiny, they’re actually extremely efficient speakers. Because they sit so
close to your ears, they can generate sound pressure levels above 105dB with very little power. Over a long
period of time, levels this high can permanently damage your hearing.

Also, keeping volume loud can isolate you from potentially important or even dangerous sounds
in the outside world. Boom operators, who often stand a few feet away from the camera or crew, find this
problem affects them the most, especially when wearing over-the-ear headsets.

They might miss the camera operator yelling directions to you, like "Get out of the shot!" Or they
might miss the sound of an approaching car or person as they move around to follow actors and
cameras.

Protect your hearing and your safety by keeping the volume high enough to hear what’s going to
tape, but low enough to hear what’s going on around you.

Between scenes, it’s a good idea to either pull the headphones off or unplug them to let your ears
rest. Don’t adjust any levels, because you’ll need to maintain consistency in the sound tracks. But do
something to give your ears a break. Once tape rolls, pop the set on, or plug them back in to hear the sound
from the mikes.

Graduation

Recognizing audio problems and correcting them before they make it to tape is what separates an audio
expert from an amateur. Knowing how to handle audio anomalies simply isn’t that difficult. It’s a matter of
being prepared and paying attention.

Knowing how to use a microphone is arguably more important than knowing how to use
headphones. Getting the best audio, however, depends on using both during the production process.

Hopefully, these simple lessons can help you get one step closer to perfect audio.

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