Sound Reasoning: Interview Audio

If you’ve planned an interview for an upcoming video project, you’ve probably thought about more than just what
questions to ask. Perhaps you’ve wondered where to stage the interview, or how to arrange the lighting.

But have you thought about the audio? Pay careful attention to recording it well, because when people watch an
interview, they want to hear what your subject has to say.

Stick with us for the next few pages, and your interview audio will come through loud and clear.

Audio Matters

Though the word interview takes its meaning in part from the ability to see (view), the voice of the
interviewee is more important than their visual image.

Things like body language and facial expressions work with the voice in conveying meaning, so good visuals are
important too. However, the instinctive communication woven into a voice is one of the great assets we have as
videomakers. The sounds of the human voice–the subtle changes in pitch and tonality–tell us as much as
the words themselves.

Recorded well, the emotions expressed in a person’s voice can form the backbone of a documentary video.
Instead of having to write pages and pages of narration, the answers and emotions from an interviewee can often tell
the story for you.

Good interview audio also lets you link those emotions to other relevant visual elements. It can tie seemingly
disparate photos, slides and video footage together in a way narration can’t.

A poorly recorded voice does none of these things. If you ignore sound quality get bad audio in your interview,
the speaker may seem somehow unimportant or unreliable. If you choose instead to paraphrase their answers, you’ll
trade a compelling subjective voice for a restrained objective one.

Ultimately, bad audio will make an audience lose interest in your show. Think about the last documentary you
saw. How often did the producer chose to insert relevant images over the sound bites from an interview? Would
those segments have been as compelling if they’d chosen to paraphrase answers in the narration? Would they have
been as effective if the voice was distant or distorted? Probably not.

Give your subjects the most credibility, yourself the most flexibility, and your audience the most entertainment by
properly recording the audio in an interview.

Which Mike?

For many interview situations, the lavalier mike, or lav, is best.

Lav mikes work well because they record great sound without drawing attention to themselves visually. They clip
unobtrusively to shirts, dresses, ties and jackets. They come in hard-wired and wireless setups, so you can capture
great sound regardless of where your subject may roam.

An excellent alternative to the lav is a stick or shotgun mike mounted on a boom. Boom miking picks up sound
almost as good as a lavaliere without having to mount a mike directly on the interviewee. It does, however, require
you to bring along an extra crew member to operate the boom and monitor the sound.

If you don’t have a lav mike or an extra person to run a boom, consider using a stick mike or a camera-mounted

Stick mikes are great for traditional "man-on-the-street" interviews. Shotguns work well for the one-man-band
who shoots the footage and asks the questions, too. The sound isn’t quite as clear as a lav or boom, but it’s better
than the standard camera mike.

After you’ve chosen the appropriate mike, you need to know where and how to place it to get the best sound.

Mike Placement

For lavlier mikes, the ideal position is in the middle of the chest, typically clipped to a shirt, tie or coat lapel. You
usually get the appropriate clips when you buy the mike.

Avoid the practice of clipping the lav to a shirt or tie without first hiding the cable. Visible cables are a sign of an
inexperienced or lazy videomaker, and may distract the audience.

Before you actually hide the wire and attach the mike, take a moment to explain to the interviewee where the mike
and cable need to go. Most people (especially women) don’t like it when someone starts grabbing at their shirt. Be
courteous and professional, and let them help you attach it. Better yet, let them attach it themselves.

Hide the mike wire by running it inside a shirt or coat. For example, if the interviewee is wearing a dress shirt,
you can slip the mike inside the shirt between two button holes just above the waist. Sneak it back out near the
middle of the chest, and clip it either to the shirt itself, or to a tie if they’re wearing one.

If they’ve got on a T-shirt or other collarless shirt, you won’t have a place to easily clip the mike. You won’t have
an easy way to hide the cable underneath the shirt, either. It often works well to clip the mike to the collar itself, or
gather a bit of the shirt material near the center of the chest. Put this little clump of fabric inside the clip to secure the
mike in position. Some T-shirts have pockets which also work for clipping.

When clipping a mike to a shirt or lapel, you may have to choose either the right or left side. If your interviewee’s
head is turned to one side while they’re talking, clip the mike to that side of the shirt or lapel for better sound.

Sometimes it’s necessary to totally conceal a lav mike. The best place to hide it is inside a coat or jacket. You can
use a small piece of duct tape on the lower part of the mike to hold it in place. Be warned: rustling fabrics may show
up as rumble on your audio tracks, depending on the sensitivity and location of your mike.

If you’re working with a wireless lav mike, the same rules apply for placing the mike and hiding the wires. You
can often hide the transmitter in the small of the interviewee’s back.

If instead you choose the boom mike setup, hiding cables won’t be an issue. The key to making the boom work
best for you is having a well-trained boom operator.

The person holding the boom should get the mike as close to the subject as possible without getting it in the shot.
Typically, the mike picks up best when suspended just above and in front of the interviewee, with the pickup aimed
toward their mouth. The operator also needs to stand fairly still to keep movement noise down.

If interviewer or interviewee is holding a stick mike, have them aim the mike across their mouth at a slight angle
instead of speaking right into it. This helps reduce pops and breathiness.

If the situation is noisy, get the mike as close as possible to help isolate the interviewee’s voice from the noise. If it’s really loud, you may have to live with some pops or
distortion just to hear the voice at all.

With a shotgun, the best you can do is point it toward the interviewee; the highly-directional pickup pattern does
most of the work for you. The closer you can get to the subject, the better the sound you’ll get.

This "closer is better" rule applies for all microphones. The lavalier mike sounds great because it’s about as close
to your talent’s mouth as you can get.

Setting and Matching Levels

Once you’ve chosen the appropriate mike and positioned it, put on headphones and check the sound. Roll some
tape, and ask the interviewee to talk for a moment. Ask them to say their full name and spell it. This helps you
properly identify them if you use a titler.

If you notice their voice lacks high frequency sparkle, make sure the mike is pointed toward their mouth. If it’s a
lav, make sure it’s not tucked too close beneath the chin or behind some fabric.

If you hear pops or breathiness, the mike is too close to their mouth. Put more distance between your mike and the

Conversely, if you hear lots of echo or other ambient noise along with their voice, the mike is too far away. Try
moving a lav higher on the shirt or tie; move a boom or stick mike closer to their face.

If your camcorder has manual audio input level controls, adjust them so the signal doesn’t overload when their
voice gets louder. This is tricky because you may not get a maximum volume out of your interviewee when
checking levels. Once they’re answering questions, however, their voice may rise as they make a point.

You can compensate for potential level jumps in one of two ways: switch the audio input level to automatic and
let it manage sudden changes, or manually set the level a little low so peaks won’t distort. Setting levels manually
sounds better. With super-quiet PCM and VHS hi-fi audio tracks, there’s no need to worry about hearing tape

Some videomakers like to use the interviewer’s questions in the finished video. If you decide to try this, be aware
that the two voices must have similar levels and tonal balance to avoid distracting the audience.

A boom-mounted mike is a good choice for these situations. If the interview takes place at a table or on a couch,
try suspending the mike above and between the two subjects. As the conversation moves, gently turn the mike
toward the person talking for the best sound.

Stick mikes work well if you’re shooting the "man-on-the-street" type of interview. Just have the interviewer
point the mike toward themselves during the question, and toward the subject during the answer.

One problem with these methods is that they use only one microphone to record both voices. The control of the
audio levels and tonal balance is in the hands of either the boom operator or the person holding the stick mike.

For more control over levels between the interviewer and interviewee, use two lavalieres. Match the levels
between the two by listening carefully through headphones to a bit of normal conversation. You should hear nothing
but very subtle level differences when monitoring through headphones. Positioning the mikes differently may help
balance levels.

If you record each voice on a separate channel, you can fix any minor level differences you missed at the shoot
during the edit session.

Multiple Interviewees

Sometimes you need to interview an entire group of people at once. For example, you might be talking to a panel of
experts, or a few members of a family at the same time. In these situations, it’s very difficult to get precisely
matched levels; there are simply too many variables.

Whether you interview two people or 10 people together, the rule is that every person should be at an equal
distance from at least one microphone.

When you use this method, expect a bit more ambient noise than usual. You can minimize the effects of this,
however, if you set up and mix properly.

If you interview more than two people at once, and each one has a mike, you might end up with more mikes than
audio tracks. In this situation, count on bringing a mike mixer and an extra crew person to operate it.

Matching levels during multiple-subject interviews is critical because you can’t fix the mix later in the edit. The
mix you generate on the shoot is the one you’ll ultimately use, so it’s got to be as close to perfect as possible.

When setting up a mixer, set each mike level independently. However, don’t leave them all "open" during the
interview. This can cause both cancellation and ambient noise problems.

Each mike you use will pick up ambient noise. When a channel on the mixer is open, this noise adds to the final
output, which ends up on your tape. That means that if five mikes are open at once, ambient noise may be up to five
times louder than normal.

Also, when all the mikes are open, subtle phasing differences can cause them to cancel each other out. That means
voices may actually "disappear" in the mix, despite being close-miked.

Instead, do your best to anticipate who will be talking next in your interview, and open only their microphone. It
helps to arrange the questions ahead of time, and direct them at specific members of the panel or group. When
mixing on the fly, try to leave no more than two mike channels fully open at one time to minimize ambient

A good technique is to never bring a mike channel down all the way when a speaker is finished. If you leave every
mike in the mix just a little, you’ll at least get some audio if a new speaker catches you off guard. You’ll pay
a small penalty in extra ambient noise, but this may be preferable to cutting off someone’s first few words.

If multiple microphones aren’t feasible, try creatively positioning one or two mikes to record all of your

A boom-mounted mike works well for recording small groups, especially if they’re seated together, perhaps in a
small circle.

For a pair of people, a lav might work well. Seat your subjects close together, and clip the mike between them on
either a lapel or shirt pocket. Position it as low as possible for the best balance between the speakers. This gets great
audio from the person wearing the mike, and nearly that good from the person next to them. It’s a low-budget
solution, and it works quite well.


A final helpful hint for any interview situation: record a few minutes of silence at the location before you start your
interview. This is helpful if you need to "open up" the audio. In other words, if you want to extend the time between
an interviewee’s sentences, a cut to silence might be noticeable, or even a distraction. Instead, cut to the ambient
noise to disguise the edit.

When the audio is recorded well, the authority and credibility of your source comes through load and clear.
Combined with good images, this will ultimately add impact to your videos.

The Videomaker Editors are dedicated to bringing you the information you need to produce and share better video.

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