Capturing Sound in the Field

With the advent of mp3 players, portable audio has become a household convenience. Lots of mp3 player brands have built-in microphones, and you can even go to the store and find several models for $20 or $30 that will do the job.

But recording “Great Idea No. 312” is about all these little devices are good for. Capturing good quality sound from a high-fidelity source for your indie filmmaking project is going to take more than a click-and-go digital pen.

Again, while it’s tempting to throw in reviews of specific devices of this type, I’ll refrain from doing so and instead provide you with some general guidelines so you can go to any store or website and be prepared to make an informed decision.

Bit Depth and Sample Rate

The digital standard for full quality audio recording is 24-bit @ 96k. That means that the bit depth, or the depth of the audio quality, is equal to 24 bits. The higher the bit depth, the larger the fidelity stored each time the audio is sampled. The sample rate, or the number of times an audio sample is taken per second, is 96,000.

CD Quality audio is 16-bit @ 44.1k, and for the purposes of normal recording this is considered uncompressed. When choosing an audio recorder make sure it can perform to at least these standards. Most recorders do, but not all of them support full 24/96 audio.

Connectors and Jacks

Consider how the recording device accepts input. Some have built-in mics, but it can be much more convenient for you if the recorder has the capability to connect to other microphones you connect to it. This could be done with 1/4″ TRS jacks, 1/8″ mini-plug jacks, or XLR microphone jacks.

There are a number of converters available for changing one type of connector to another, but be aware that if you want to use a condenser microphone the unit will need to provide phantom power.

Your sound recordist is going to want headphones so that he can monitor the sound and make sure the signal is coming through in a strong and consistent manner. Check whether the device you’re considering has a headphone output jack for this purpose.

Phantom Power

There are two basic types of microphones: dynamic mics and condenser mics. Dynamic mics don’t need external power in order to be used, but they also tend to provide a much weaker signal when recording things at a distance. Phantom power is a feature that increases the voltage of an audio recorder so that it can accept input from a condenser microphone. Condenser mics do require phantom power, or you’ll get no signal at all from them (or at least an incredibly low signal) but they are the best for capturing room noise and distant sound sources.

Internal Memory

Take note of the recording device’s storage media. Many have their own built-in memory with the ability to save data to a removable memory card. Others can be connected directly to a computer via USB or other port and will record audio directly to the computer itself.

Size and Weight

Your sound crew is going to have to operate this piece of machinery, and if you are using a single recordist armed with a boom pole, shotgun mic, and your recorder, it’s important that he is able to wear it on him or keep it close by for easy access to its record and stop buttons.

Some devices can be slipped into a pocket or clipped to a belt, but certain recorders are more bulky and cannot be carried as easily. Take this into consideration and make sure you have, if nothing else, long enough audio cables to allow your recordist to move around as he captures sound during your shoots.

If you believe an acting performance or a beautiful scene can solidify an emotional reaction from an audience alone, think again. Your film score, if implemented properly, has the potential to do more to set the mood of a scene than the visuals themselves.

While it’s never legal to use copyrighted music in any form without permission, no one’s going to bother you if you make a no-budget movie to show friends and family and use your favorite inspirational U2 song in the background. As long as you don’t try to sell or distribute your film, your film score can technically contain any music you want.

Just as a warning, YouTube™ will almost automatically toss any video that contains a song whose
artist or label has banned it from use, and they’ll check submissions for those songs fairly regularly. You might be able to get away with using copyrighted tracks as film soundtracks, but in most cases its easier to just use music you know won’t be disputed.

Where Can I Get Music For My Videos?

Well, there are a lot of places actually. Following are some ideas to get you moving toward assembling the quintessential film soundtrack.

What Makes Movies Sound So Good?

When you sit down to watch a film, you are immediately bombarded by an introduction that usually contains at least some sound in the background. Sometimes the opening scene includes dialogue, someone doing something or going somewhere, and all the sound effects associated with that activity. Many of these are post production sound elements that were added after the film was shot.

Of course, this is assuming you like to watch talkies, and not silent films. But since the last silent film produced by a major motion picture studio probably came out before the 1930’s, I’m going to assume that every movie you watch has sound in it. So the next time you see a movie, pay more attention to what you’re hearing and how it shapes your view of the scene and the overall story.

Even if you’re watching a foreign film with subtitles and you can’t understand the dialogue, there is a multi-layered soundtrack that is helping you to have a clear understanding of what’s going. The rest of the sound effects and the tone of the music set the stage for the plot and characters.

Sound is often overlooked because, well, you can’t see it. You may not realize what a great deal of time and precision have likely gone into creating and organizing the sounds within a given film, so I’m going to talk a little bit about sound design and the different layers of audio that go into every second of a movie.

Production Sound

This is sound in its most raw form, cinematically speaking. Direct or Production sound is the audio that’s captured at the time of filming; spoken pieces of dialogue, actual sounds from the environment, and anything else that escapes the “quiet on the set” rule. Foley is what is captured with the standard audio rig using a shotgun microphone held above the action and outside the frame.

But if film studios were to just record the production sounds and leave it at that, they’d end up with a movie that feels more like a home video or a reality TV show. Part of the magic of the movies is that sounds surround the viewer, and not the camera. In order to make your viewer feel like they are inside of the reality you’re striving to create with your film, you need to orient those sounds so that they seem as real as possible to the person in the theater chair or on their couch at home.

Ambience

The sounds of a spring day; birds chirping, children playing in a nearby park, bicycle spokes ticking as cyclists ride by. A bustling city street with its car horns, sirens, footsteps on pavement. These are examples of ambient sound, which is sometimes recorded on set or on location, but it can also be added in later as post production sound.

Ambient noise is essential for selling the idea of a particular environment. If the characters in a movie are supposed to be on a space ship or in a submarine and there is no deep, constant rumble in the background it’s going to sound like they are on a hollywood film set instead of in that particular vessel. So ambience can be a very subtle, yet effective tool in your arsenal.

Foley

The element of cinematic magic begins to come to life when you talk about foley sound. Foley sounds are specific and precisely timed effects recorded in a studio during post production – after the initial filming has taken place. These post production sounds add depth and super-realism to a movie. Often objects that make unique sounds are substituted for what is actually making them on the screen: leather gloves flapping as a bird flaps its wings; a fist hitting a piece of steak as a punch lands in a henchman’s gut, a handful of uncooked spaghetti snapping as a bone breaks.

Foley doesn’t have to be recorded in time with your videos. As a matter of fact you can set up to record sound wherever you want, make a bunch of noise and then place each sound effect along the timeline of your video editing software in sync with the footage. It’s a creative way to make sure the thud of a body falling or the sloppiness of a wet kiss can be heard clearly.

With this type of sound you also gain something very powerful; suggestion. You can show an axe being raised above an unsuspecting victim’s head and then cut to a different shot as the sound of the axe falling into flesh is heard. In other words, foley sound allows you to tell your audience what is happening without actually showing it to them.

Music

Among the various types of post production sound, music is perhaps the most effective when it comes to setting the pace and mood of a scene. A slow ballad with strings in a minor key conveys sadness and loss, while an upbeat techno hit with a pounding bass line gets the viewer’s pulse racing during an action scene.

Even in scenes where it sounds like there is music playing in the background, such as during a big party where there are lots of people talking, these are almost always post production sounds. Adding them in later offers continuity between cuts and also makes it easier for the filmmakers to record dialogue during the scene. You should use this method in your filmmaking whenever possible so that you can work with isolated sounds in your post production environment.

Production music ranges from scores composed specifically for a film to songs by popular artists used as a tune that appears on the car radio or alarm clock of a character in the movie. Your videos can take advantage of this kind of ingenuity as long as you pay attention to copyright law and make sure your source of music is being used legally.

How It All Fits Together

Blades of grass sway in the breeze as a steady rumble grows in the distance. Butterflies flit through flower beds in the sunny field. The rumbling gets louder amid the peace of the serene summertime scene. Suddenly, a hundred men on horseback appear over the rise, their screams echoing eerily across the plains as they charge into battle in slow motion. Hoofs pound the earth, kicking up dirt; the manes of the horses and the long hair of the warriors both now sway gently in the same breeze that moves the grass. The look of fear crosses over their dirt-covered faces, but they press on toward the enemy.

This is all just writing, of course, but I’m sure you can imagine or you might have seen a similar sequence take place in a movie. Sometimes silence is used in a slow motion segment to convey a suspension in time, but still the sounds of the men yelling their battle cries, the horses’ hooves hitting the ground, and even the breeze lightly moving across the fields, must be captured and put in place in order to bring the scene to life. When the film finally returns to real-time motion, an epic song of battle might begin to play in the forefront, stirring feelings of tension within your audience.

You can see how choosing the right mix of sounds can turn an ordinary scene into a great one. So don’t overlook the power of suggestion that sound offers in your videos!

You might have the finest actors in the world delivering lines and the most high-quality film cameras on the market capturing those lines, but none of that makes a difference if you don’t know a thing about recording dialogue – learning how to record their voices properly is an important step in the process.

Even in some of the major motion picture studios, dialogue that was not captured effectively on set – whether it was the performance or the sound quality – sometimes has to be re-recorded during post-production. But without an equipment setup that allows the actor to see himself or herself on the screen as he or she overdubs the lines, it’s very difficult to do so accurately. In fact, it’s pretty hard to get a good take even with this type of setup, and at the very least it’s incredibly time-consuming.

So you’ll save yourself lots of trouble by doing things right and getting your dialogue recording loud enough the first time around.

You might be used to seeing YouTube videos that consist of a person aiming their webcam or computer-linked camcorder at themselves and making “talking head” style videos. You’ll often notice that these people’s voices start to get a bad case of tunnel syndrome the further they get from the camera.

This is because when you record sound indoors the distance between the microphone and the audio source makes a difference in how the mic receives the sound. The farther away the source, the more the sound bounces off of walls, floors, and any other smooth, flat surface that can reflect it before getting back to the mic. It doesn’t help that the onboard mics supplied with most video cameras are of less than superior quality.

Up Close And Personal – Types of Microphones

You can use a shotgun or lavalier microphone to bring your sound source closer to the recording device. Do this by placing the mic just outside the shot or strategically hidden within it.

Lavaliers are the small mics that clip to a tie or shirt and can be either wireless or wired. These are generally suitable for interview-style filmmaking, but you’re not going to want one hanging off your talent while you film action shots or dialogue during a dramatic scene.

A shotgun mic is the standard device used to grab audio on film and television production sets. As I explain on the sound design page, the shotgun mic is suspended over the sound source and outside the frame on a long boom pole.

From its position above, a shotgun mic should pick up a certain degree of room noise and a good strong signal of your actors’ dialogue recordings. A good cheap shotgun mic to look at is the Audio Technica ATR-55. It does a great job but doesn’t cost lots of money.

Check Your Work

While on set, it’s important to have someone monitoring the audio signal to make sure it’s coming through properly. Usually this is done by the sound tech or whoever is operating the boom – they should wear headphones to keep a constant gauge on noise levels and capture quality.

If for whatever reason it’s impossible for you to monitor the audio from an external mic, at least do a quick playback before you pack up and go – even better, test your setup before you get into filming. You can avoid lots of headaches this way, like getting the perfect shot on tape only to find that the audio to go with it is scratchy or muffled. There are some tricks you can pull in post to work some wizardry on some trouble spots, but not everything can be fixed this way.

I’ll give you an example of how not testing before a shoot has caused me problems before. I had set up to do a shoot of some oral presentations for an Emerging Leaders conference, and for lack of a boom operator we decided to use a hanging mic suspended from the ceiling to grab the room noise.

To do this, we set temporary hooks in between the ceiling tiles and ran the audio cable along the ceiling from the camera to the hanging mic. We did our shot test and everything seemed okay, but the fluorescent lights in the ceiling made me nervous so we ran a second test with me holding onto the metal pieces of our tripod. Everything was still fine when we ran playback.

It wasn’t until we had recorded about two hours of footage, torn down our equipment and gotten back to the editing bays that I found out there was a horrendous buzzing in the footage. Wondering what it was from, I watched a little longer and realized that it happened only when I was touching the camera, not the tripod.

Unfortunately I had been re-framing my shots pretty often to compensate for people moving around the room. The buzzing from some unknown aspect of the room lights, whether it was the way they were grounded or the audio cable picking up pulses because it was so close to them, was so intense that even after noise reduction, notch filtering, and every other tweak I could think of, the audio signal was still unusable. The shoot was scrapped and about twenty presenters never got their products!

Don’t Screw It Up!

I don’t tell you stories like this to give you a sense of dread, but in a way I hope you get hit that way. I want you to be cognizant always of the unexpected situations that can arise. Pilots flight check before they take off, yet planes still crash; you can never possibly account for every little problem that will come up. But checking and re-checking your work can help you avoid lots of pitfalls. Recording dialogue is one of those areas where a proper setup and preparation works wonders for your final product.

Using Background Music To Set The Mood

Say you’ve already assembled a bunch of background music for your film, or you at least have some in mind and know where you want to put it. If you can’t recognize instruments by how they sound, or don’t have much experience in the way of identifying them, here’s a quick breakdown of some of the fundamental elements of organized sound to help you make sure none of your scenes go without just the right background music.

Lyrical or Instrumental?

You can almost always use instrumental background music (ie., music that has no lyrical content) to flesh out a scene. There are only certain instances, however, where lyrical music will work. In cut scenes or montages, for
instance, it is generally acceptable to use pop songs or other lyrical music to fill the space, but in scenes with
dialogue its use may be distracting. We’ll talk more about lyrics and vocal content later; first let’s go over some
of the ways you can identify appropriate sounds for instrumental (non-lyrical) music.

Orchestration

Orchestral music comes in many forms and styles; it’s generally composed by using several different
instruments, or groups of instruments, to create layers of sound. The basic units in a full orchestra are
percussion, strings, brass, and woodwinds. Each can be used in a number of
ways to build tension, soften a moment, or provide an interlude to the action.

Percussion

This section includes not only ‘toneless’ instruments like drums and shakers, but also xylophones, timpani,
and bells. Percussion instruments usually include anything that is played by being struck with a hand, stick, or
other implement.

Percussion’s main focus is to bring rhythm to a song; it provides a beat and moves the piece along. Music
without percussion is generally classified as ambient because it is more like a presence in the air than a
steadily moving piece of background music. In practice, percussion has a wide array of uses depending on the beat it
produces. It can add a relaxed tone if the beat is swingy or jazzy, while a driving rhythm adds tension.

Strings

Violins, cellos, the upright bass, guitars, harps, and even pianos are all stringed instruments. Stringed
instruments use tightly wound cords that vibrate at a certain frequency when strummed, rubbed, or
plucked.

The strings are the glue that holds a piece together; their presence envelopes a song and add padding to
it. More than any other instrument group, stringed instruments are masters of sustain and
resonance. This means that a note on a stringed instrument can be held for a long time after the
musician has played it. Other groups have instruments like this, but just about every stringed instrument has
this ability without any extra effort on the part of the musician.

Strings can be used in the background or at the forefront of a musical piece, but in either case they are
exceptionally good at building or breaking down tension.

Brass

Instruments included in the brass section are trumpets, french horns, tubas, trombones, and coronets.
Sound is produced when the vibration of the instrumentalist’s lips in conjunction with the mouthpiece, funnels
the air through a series of tubes. By using buttons or finger pads to shorten or lengthen these tubes, the musician is able to change the pitch of each note.

Brass instruments are bold and loud, and they can add strength and presence to a song. Whether it’s a
rousing, triumphant piece or a quiet and flowing melody, brass instruments are used to convey confidence,
fortitude, and resilience.

Woodwinds

Woodwinds provide a smooth, flowing texture to an orchestral arrangement. They include the clarinet, oboe, saxophone, piccolo, and flute. A woodwind makes sound when the musician blows through it, either causing a reed to vibrate or a seal of air to form across a properly aligned hole in the instrument.

The audible quality created by woodwind instruments can be deep and sombre or light and flitting. Either way, they tend to be warm and fluid.

Instrumentation and Orchestral Music

Knowing how these four instrument groups work together, you can start to get a feel for what kinds of things you should be looking for when assembling your background music. When was the last time you watched a horror movie that didn’t have lots of creepy woodwinds in the background? Or a war movie with no brass? A comedy without lots of catchy beats and irreverent melody lines?

Vocals

A person singing is often one of the most recognizable traits of a song. Not only do most humans have a higher capacity for identifying the sound of a human voice than we do an instrument, but so long as we can understand the words they’re also more meaningful and can be easier to remember. The rule for using songs with vocals within your background music is to either place them where there’s no dialogue, or keep the volume very low when you use them in speaking scenes.

Electronic Music

With looping programs, it’s possible to create free background music that isn’t derived from any type of real-life instrument. These programs or other techno, house, or trance music may be the perfect thing for your video or film’s background music, and in these cases just use whatever sounds good.

Be sure to check out my other articles on sound design and effects for more information. There is a ton of information throughout the site that will help you build your familiarity with and mastery of various audio production techniques and methods in addition to just background music.

Let’s imagine you’ve just gotten the most perfect audio recording ever, with no effects or filters having been added to it. The audio compression is therefore non-existent, and all the levels are great. The quality is awesome, and there are no unwanted background noises.

Now unless your talent are doing their lines completely deadpan and monotone with no inflection or dynamics changes, some sounds will be louder than others unless you use audio compression to fix the problem.

In post-production you can use the technique known as audio compression to make dialogue and other vocal noise easier to hear above the other sounds going on. Most digital editing programs have some kind of plugin that performs compression for you.

While you can use audio compression effectively in your indie projects, it’s also used in lots of ways in the recording industry. Listen to any major-label song you own, and you’ll notice that even in songs where the vocalist’s voice goes from very loud to very quiet, the loud parts aren’t ear-splitting and the quiet parts aren’t impossible to hear. This phenomenon is caused by the use of compression.

How Compression Works

In order to get the quietest parts of an audio recording loud enough, you need to boost the signal during
those parts. But trying to boost only the quiet parts would be tedious and time-consuming, so a compression filter boosts the signal for its entire duration.

The problem now is that the loudest parts are also louder by the same amount. To keep these loud parts
from clipping or distorting, the compressor employs a certain ratio of limitation at a threshold. In other words, it tones down the loud parts by cutting them off above a certain loudness that you specify.

Ratio and Threshold

To do this, you set the point where you want the compressor to start restraining the audio, say -15dB. Then you set the ratio of limitation; it might be 3:1 or 5:1 or infinity:1. Three-to-one, for example, means that for every three decibels the sound signal pops up above the threshold, the audio compressor only lets one decibel “get past.” A 1:1 compression ratio, therefore, isn’t really compression at all, and an infinity:1 ratio is called a hard limiter because it doesn’t let even one bit of sound get louder than the threshold.

Attack and Release

The attack and release settings are measured in ms (milliseconds), and are simply
measures of how quickly the compressor acts on audio that gets too loud and how quickly it stops acting after the audio has gone back below the threshold. Attack and release settings can be as little as 0ms, but setting them to act too quickly or with too much delay can cause the compression to be ineffective, so each piece of audio is different.

Going to Extremes

So now you may be wondering why you shouldn’t just use a hard limiter with 0 attack and 0 release, the most stringent settings you can push on your compressor. Well, it’s no different than any other time you alter a digital file, whether it be audio, video, an image, or another piece of media. When you do something that changes audio dramatically from what it wants to do naturally, you run the risk of making it sound “canned” or artificial.

Just try some extreme settings with your audio compression plugin and you’ll see what I mean. If you pull off the attack too much, loud audio will get through before the limiter turns on. If you take the release out too far, the limiter will stay on when it doesn’t need to be on and cause muffling or echoing. Using a hard limiter on audio that’s too loud already can make the loud parts crackle and sound over-modulated.

The Product

With a good audio compression setup, you can take lines of dialogue – or entire scenes worth of it – and smooth it out so that the volumes are consistent throughout. Audio is a tricky medium to work with, so there will never be a hard and fast rule on when to use audio compression and when not to. Each time you tweak a piece of audio you’re changing the fundamental signal, so use effects and plugins such as audio compression sparingly when possible, and with good judgment when necessary.