Video production isn't only about what you see. Just as important, though often not given the consideration it deserves, is what you hear. Sound quality considerations should be an equally significant part of most video projects.

Everyone's needs and expectations are different, so all I can hope to accomplish here is to give you a good foundation for approaching sound recording with the goal of getting the best out of what you have at hand. The main focus of this article will be techniques for recording good voice (speaking) recordings, but many of the ideas apply to any kind of sound recording.

SECTION ONE: Understanding Microphones

Microphones come in all kinds of designs and variations. The two main things to consider when choosing a microphone are design type and directional response pattern.

Design Types

Dynamic mics output a small electrical voltage produced as the result of a wire coil sliding back and forth along a magnet (electromagnetism). The coil is connected to a diaphragm which reacts to air movement. Basically, the opposite of a speaker - which can also be used as a microphone, though not a great one. Dynamic mics are rugged, dependable, and typically low cost. No external power or batteries are required.

Ribbon or velocity mics are related to the dynamic design. Instead of using a coil however, a thin conductive strip is suspended between two magnetic poles. These mics can be very fragile; but, they have seen a resurgence in popularity in recent years, probably due to improved construction techniques and materials which make the mic a bit more hardy. Ribbon mics exhibit a superior transient response, and exhibit a characteristic ringing sound that lends a warm texture to acoustic instruments and vocals. They tend to be a bit more expensive than dynamic mics and are roughly in the same price range as quality condenser mics.

Condenser mics require either a battery or +48 V (phantom power) power supply to do their job. In these mics, an electrically charged diaphragm reacts to air pressure causing voltage fluctuations on the back of a plate - which produces an electrical "picture" of the sound. These mics are particularly sensitive; however, their softer, brighter, more open sound is particularly nice for female voices. Condenser mics are more vulnerable to daily wear and tear, and more sensitive than dynamic mics to extreme environmental conditions.

Directional Response Patterns

The shape in which a microphone is able to hear sounds is called a directional response pattern. The most common of which are: omnidirectional, bidirectional, and cardiod. Some mics are switchable, offering several different response options.

Omnidirectional mics have a pickup response that is equal from all directions. This is usually not a good selection for voice-over work as it will pick up too much surrounding ambience.

Bidirectional mics have a response pattern shaped like a figure-8, with sensitivity on the front and back. This would be ideal for recording two people at the same time. Facing them towards each other and placing the mic in the middle, will provide very strong pickup for each person, while rejecting unwanted noises from the sides.

Cardioid (unidirectional) pattern mics would be a good choice for recording a single person. They provide a heart shaped pickup pattern with sensitivity on the front and sides. Variations include: hypercardioid and supercardioid.

Choices, Choices

There are lots of microphones to choose from, and each with a mind of its own. Just like everything else, the more accurate you want your recorded sound to be, the more it's going to cost you. Obviously, a $3,000 mic is going to be able to capture the subtle nuances of sound better than a $300 mic. But, even a $3,000 mic won't fix a badly delivered voice-over or otherwise poorly recorded track.

[Editor's note: All following prices are manufacturer's suggested list.]

It isn't necessary to capture sound as perfectly as possible. I have done some of my best voice-over tracks with a Shure SM58 (under $200) or a Sennheiser MD 421 ($485). Currently my favorite mic is a RODE Classic ($2,000), but only because of its added versatility - featuring nine selectable pickup patterns, gain control, and bass roll-off functionality. But, I could just as well record acceptable voice-over tracks using models which cost less than $200 from audio-technica, beyerdynamic, Electro-Voice, Fostex, or Peavey.

[Editor's note: At young monkey studios, we're very fond of the beyerdynamic M 88 ($399) hypercardiod dynamic mic. We've been using one for 14 years, for just about every purpose imaginable. It's a well respected microphone. Unlike many other technologies, older mics aren't as quickly surpassed by newer ones. Microphones are like aged wine.]

If you don't have a large budget for a microphone, then perhaps a good dynamic mic like the Shure SM58, Sennheiser MD 421, or even an Electro-Voice ND167 ($188) would do nicely. If you prefer an airy sound to a warm feeling one, or if you regularly use female voice-over talent, then you might consider a condenser mic like the audio-technica AT4033a/SM ($725), or the Shure KSM32 ($959). Of course, if money is no object, then go for the gold with an AKG SolidTube ($1,165), audio-technica AT4060 ($1,695), or RODE Classic II ($1,999). Sound expensive? Well, in the land of professional microphones we're just scratching the surface. The Lamborghini's of the microphone world come from Neumann, who offer mics ranging from $2,000 - $5,000. Vintage models could cost you as much as a two-story home mortgage. The AKG C 12 VR ($4,821), Sony C800G ($6,550), and Manley Laboratories Gold Reference ($8,000) are also high-end favorites.

(Bob Ketchum, the Mystic Maven of Microphones, reminds the reader that sometimes a microphone is just a microphone - unless it says Neumann on it.)

SECTION TWO: Recording Environments

The most common approach used in professional sound studios, is to create an acoustically "dead" booth in which to record your sound. Then, using any of a variety of signal processing devices (reverb, delay, etc.) enhance the sound to taste. Alternatively, and the more affordable option, you can take advantage of the acoustics of an existing room. This approach is obviously the easier of the two; but if it results in unwanted ambience in a sound recording, it can be very difficult to remove it.

Singing In The Shower

You've probably heard it said that even a bad singer can sound good when singing in the shower. This is because, typically, bathrooms are very reverberant. It's like having many clones of yourself singing all at once - If you get enough bad singers to sing together, they usually don't sound so bad. So, a bathroom is the obvious place to try first if you want to add some natural reverb to your voice-over. It may sound funny, but many studios have achieved great results in a bathroom or shower stall. A wood paneled jacuzzi room can also be a great acoustic environment. If you decide to make use of existing ambience, you may still want to make a few slight adjustments to the environment.

Now, Clap You Hands

First, let's examine the acoustics of the space you're considering using. The simplest test is to stand next to a wall in the room and clap your hands together once, fairly hard. Listen carefully. Do you hear echoes, reverberations or a ringing sound? If the room is in a garage or concrete basement, you'll probably hear a lot of ambient reflections. Next, you should do some test recordings. You can do this with your own voice if you want, though it might be distracting for you to listen to. Ask a friend or family member to sit in for this test - someone whose voice is similar to what you'll be using for the voice-overs. After a few test recordings, put on a pair of headphones and listen closely to the playback. Do you hear unwanted bass, fluttering high-ends, or bouncing frequencies? If so, there's a few things we can do to reduce them.

Out Out Brief Noises

To avoid getting into too much complexity about principals of sound, it's more sensible to just provide you with some basic ideas and let you experiment with whatever you have access to.

Acoustic diffusion and absorption materials come in all sizes and shapes, and at a cost that can fit any budget. You can effectively use anything from the time-worn (though visually impaired) egg carton treatment, through to professional diffusors and sound tiling. On the easily affordable list, we can also add carpet, foam, blankets, mattresses, curtains, sleeping bags, fiberglass insulation, and even styrofoam.

Different materials diffuse or absorb different frequencies. Carpet and foam (or even carpet over foam) will absorb standing bass waves and help tighten up a room - acoustically speaking. Styrofoam panels will absorb upper-mid frequencies and even some extreme highs. Packing blankets are great for isolating sound and absorbing ambient noises, you can never have enough of them. As a general rule, porous materials (such as lumpy mattresses or overlapping blankets) absorb high frequencies best. I have even reduced high-frequency slap and tightened up a room by hanging an army surplus parachute from the ceiling.

Once you've determined what materials achieve the result you're after, you should then decide how permanent you want the solution to be. Will sound recording be a frequent occurrence, perhaps suggesting a more permanent solution? Or would less frequent use imply that an approach allowing for a little advance set-up would be more sensible?

The simplest approach is to just nail the materials to the walls. If you're cosmetically conscious, you may want to create a wooden frame of some sort to improve the look. Another good trick is to arrange pillows, sleeping bags, or carpeting as necessary and then cover it all over with burlap or muslin. If possible, leave an air pocket of several inches between the treatment and the wall. This will act as a bass trap, decreasing lower-mid and mid-bass frequencies.

You can make low-cost bass traps using rubber trash cans (35-55 gallons). Drill them full of holes, fill them up with fiberglass insulation, and place one in each corner of your room. Or build lattice frames of wood slats about 3' wide and the same height as your ceiling. Cover them with muslin or burlap. Place this frame diagonally across a room corner and fill behind it with R-30 insulation. Leave the foil on, foil side out toward the room. Repeat this for each corner.

Also, if you hear about any large corporations going out of business, be sure to attend the auctions. Room dividers are a common find, and great for quashing ambient noises.

Absorbing Junior

Unless you've designed a completely sound-proof booth, you're most likely going to have all kinds of unwanted noises seeping in through the walls and windows, especially if you are located near roadways. There's nothing quite like the sound, and resulting frustration, of a tractor-trailer passing by, right smack in the middle of the quietest part of your narration... a not-so-quiet son insisting on playing just outside your studio ("Robert!")... the constant hum from a nearby air conditioning unit... or fans blowing away in a futile attempt to keep your audio visual gear cool. Escaping these kinds of sounds is a tough assignment.

You can start by closing windows and covering them with blankets or a mattress. Also, close doors and poke towels or weather-stripping into the spaces at the bottom. If feasible, consider replacing hollow doors with solid ones. It also helps to open closet doors, move couches and padded chairs slightly away from the walls, and reposition objects/furniture in such a way as to reflect sounds from parallel walls. Room resonance is more troublesome in a cubical room. It's less of a problem if the length, width, and height of the room are all different.

Here are a few more obvious, but often forgotten, tips for reducing room noise while recording:

Turn off appliances and telephone ringers while recording.
Unplug the refrigerator - and don't forget to plug it back in.
Pause and wait for ambulances, tractor-trailers, and airplanes to pass.
Make sure the air conditioning doesn't turn on during recording.
Turn off all fluorescent lights.
Only turn on the studio equipment you are using to record.

To improve imaging and frequency response in your mixing/listening environment, place foam on the wall between your monitor speakers.

Bigger Budget Alternatives

If you have the budget for it, and desire a room which has a more professional appearance, you may want to invest in the purchase of specialized acoustic treatments. Consider products from Auralex Acoustics, Acoustic Sciences Corporation, Acoustical Solutions, or RPG Diffusor Systems.

(Bob Ketchum, the Anarchist of Acoustics, has just left the recording booth to wage war with the air conditioner, the telephone, and that annoying drip in the bathroom sink.)

SECTION THREE: Voice-Over Techniques

So, now that you've got a comfortable and acoustically sound room, we need to find some voice talent to record. Let's call them the VOP (voice-over person).

Finding the Right Voice

Many of you probably don't have the budget to hire well-known and easily recognizable voice talent, so let's consider some more affordable alternatives. Start by looking into hiring announcers from the local commercial-radio stations - they've got experience, but it might come at too high a price. Then try tuning into a university radio station to hear if there's a voice you like - students are always looking for extra cash and will have had some practice at this kind of speaking. Another place to check is theatre groups - actors usually have experienced, well projected voices. A little closer to home... a friend or co-worker might have the perfect voice for the job. Or, if all else fails, you could just do it yourself.

Whoever you choose, be sure your VOP doesn't have a strong local accent (unless of course that's what you need) - finding someone here in the Ozarks, for example, who can speak without a Southern drawl may prove more difficult than you might imagine.

I am fortunate to have grown up in a resort area, so we always had a lot of relatives and guests visiting from all over the United States. As I grew into adolescence, I developed a mostly neutral speaking voice. Later when I entered radio broadcasting, this proved to be very beneficial. In time, my voice came to be in demand because I sounded like I could be from anywhere. Of course, in real life, I do have a bit of a twang. But after 15 years of radio announcing, I have learned how and when to turn it on and off. Nowadays, I instinctively slip into my radio voice the instant I put on the headphones and step up to a mic.

I'm no James Earl Jones when it comes to narration. The only time I have real resonance to my voice is after a four hour singing gig, or possibly the morning after a knock-down, drag-out, yelling match with the neighbor. I try to time those events, as best I can, to coincide with voice-over sessions. It may sound ridiculous, but you'd be amazed at the difference it can make in voice performance. After a night of band rehearsal or concert performance, my throat is fully exercised, open, and produces a much deepened voice. I was kidding about the neighbor.

Script Preparation

Scripts should be printed using an easy to read font, at least 14 points. It's important to number the pages - staples are forbidden in this work. The last thing you want is to hear a page turn in the middle of a read. To further assist in avoiding this problem, you should always try to make sure that a section of dialog never crosses over to another page. If possible, give the script to the VOP a few days in advance so they can prepare.

If your VOP will be standing, place the script on a music stand that is foam padded, and angle it to avoid reflection of sound back into the mic. Position the script high enough to avoid the VOP having to move out of the mic's sweet spot to read everything.

Sit, Stand

Whether the VOP sits or stands while speaking can have an impact on their performance. Generally, standing while reading results in better vocal control because the diaphragm has more freedom to move. I find sitting works well for me, perhaps because through 15 years of radio announcing I always sat at a console to deliver my voice work.

If your VOP wants to sit, make sure you have a sturdy, squeak-free chair for them. Also, be aware that table-top surfaces will reflect sound waves and may color their voice. Placing a foam sheet on the desk will help absorb these reflections.

Setting Up the Mic

Put the mic on a boom stand whenever possible, particularly when sitting at a desk. Desktop mic stands aren't a good idea because even the quietest movements on the desk will be picked up by the mic and amplified in your recording. If you don't have a boom stand, you can achieve the same result by placing a desktop stand on a block of foam on the desk in front of the VOP.

Also, make sure to secure the mic cord - from the mic all the way back to the recorder. The slightest wiggle or tapping of a cord will travel back to the mic and be audible in your recording.

Mind Your P's and T's

A good VOP will know how to work a microphone and make things like sentence structure and phrasing seem almost matter-of-fact. They'll also instinctively know when to back off the mic for louder passages, how to suppress hard plosives (popping P's and clicking T's), and how to avoid the "Seven Sickly Snakes Slithering in the Swamp" - also known as sibilance.

To better understand the effect of plosives and sibilance, hold your hand about an inch in front of your mouth and talk. You should feel varying amounts of air pushing against your hand. It'll be particularly strong when you say words with P's in them. With practice you can learn to control vocal airflow and reduce these problems.

It also helps if you don't speak directly into the mic. Instead, speak at a slight angle to the mic so that airflow passes by the mic, rather than being forced directly into it. A pop filter can also be a great help with this problem. These are inexpensive and can be purchased from just about any music store, or you can easily make your own by stretching panty house over a rounded wire coat hanger. Don't be TOO cheap now - this is not one of those times when recycling is a good idea, so go out and buy a new pair of hose.

If you're working with someone who doesn't have a lot of experience, or if you've decided to do it yourself, make sure you take the time to do some practice reads. When speaking, project your voice from the upper stomach, as opposed to the throat. Pace your speaking, and pay particular attention to proper enunciation.

Headphones

Headphones are an absolute MUST. Your VOP will deliver a better performance if they can hear themselves. They will enunciate more clearly, be more aware of plosives, and instantly know if they are straying too far from or moving too close to the mic. The VOP will also be able to tell how far back they need to move in order to silently take a breath before starting the next line.

Preventing these kinds of problems from happening will ensure a great voice-over, and one that requires very little post-production fixing. As often as you hear it said, nobody wants to have to fix it in post.

Be wary of the VOP that wants to hear play-back of every little nuance of their delivery. These people usually spend too much time fretting about the sound of their own voices, and not enough time paying attention to the matters at hand.

Drinks Anyone?

Having a glass of water at hand during the recording is a good idea. The longer your VOP can keep going uninterrupted, the more consistent your track will sound.

I have noticed that milkshakes and other dairy products can make my voice sound a bit thicker. A cup of hot tea with lemon in it, seems to clear up my sinuses and open my throat a bit more. A milkshake combined with hot tea would probably confuse things, not to mention just tasting plain bad.

It's Now Or Never Better

I need to stress here how important it is to record all the narration for a project, or at least individual sections of the project, in one session. After warming up, your VOP will slip into a speaking rhythm that you won't want to end. If you break the flow, for any reason (a lunch break, for example), you'll be surprised at how long it will take to return to the same feeling and pace - assuming that you even can. The differences may not be so obvious while you're making the recordings, but believe me... the moment you sit down to assemble the clips, you'll hear it all too clearly!

Countless times I have completed a narrative, only to have the client request a change that requires some part of the voice-over to be re-recorded - usually several days later. When that replacement audio is heard along with the previous recordings, it'll stand out like a sore thumb. It's always a good idea to make sure the narrative you are recording is the absolute, ultimate, final version of the script. I have actually had jobs where there were so many changes, after the fact, that it became necessary to re-record the entire narrative - just to resolve vocal continuity.

Practice Makes Perfect

You won't become a voice-over recording expert overnight. It takes a lot of practice to really perfect the process. Human speech sounds are so dramatically different and individual that there is no set way to record the voice. Every VOP you work with will require variations in your approach. Vocals are produced by interaction between the lungs, chest, diaphragm, larynx, mouth, teeth, palette, gums, and lips. The tonal combinations are virtually endless.

All the elements, tips, and situations described here present a good place to start in your quest for the perfect narrative, but by no means does it end here.

One last thing. If you've done your own voice-over and really don't like listening to the sound of your voice, ask someone you trust to listen to the play-back and then discuss it. The first time I heard my voice on tape it sounded so squeaky to me that I swore I'd never do it again. I've since learned to hear my voice the way that others do and don't mind it so much now. Not that I still wouldn't like to have James Earl Jones bequeath his vocal chords to me.

(Bob Ketchum, the Viceroy of Voice-Overs, sits up late at night just to hear "THIS is CNN!")

** Terms, company names and products contained within this article may be registered or trademarked by their respective companies.

Back to "Online Articles" Page

Back to CCS Home Page