Now that you have learned how to design and plan sound, it’s time to head into the real world and live-record the elements you need. At the base level, the categories of elements you will record are straightforward:

In this section, we will focus on production recording and effects recording, including some of the tools involved in these processes. We will delve into postproduction recording techniques and requirements, along with other aspects of postproduction sound—including music—later in the chapter.

Recording Best Practices

Before you ponder specific recording tools, methods, and situations, keep in mind some general but important best-practice concepts for recording sound:

With all that in mind, remember the following, more specific technical requirements for good recordings:

Production Recording: Dialogue

As noted, production sound involves the capture of dialogue during principal photography. That work is normally handled by a recordist, most frequently credited as a production mixer because, on-set, he or she may well be recording more than one mic or channel while using a portable field mixer and digital recorder (see here) to acquire the cleanest possible dialogue recording. The recordist will likely use a portable sound cart containing the field mixer, recorder, and lots of recording media: mics, cables, level meters, headphones, laptop, and possibly specialized equipment.

The goal of the recordist is to make sure there is a high signal-to-noise ratio, meaning no background or ambient noise or other distracting or distorting sounds bleed into the dialogue track. This goal can be challenging because sets are often crowded and noisy, with less than optimal acoustics. Indeed, for possible postproduction use, production mixers frequently ask for silence on-set and record room tone—a unique, barely audible hum, buzz, or low tone that exists in many locations due to natural phenomenon or mechanical infrastructure.

The production mixer also chooses which microphones and sound recorder to use, and will monitor and report to the director any audio problems. Thus, he or she should have a good foundational understanding of the physics of sound and microphone technology: how sound travels, bounces, or can be muffled or obscured; what decibels are too low or too high for comfortable hearing; and so on.

Often, the production mixer relies on the aforementioned boom microphone—a mic suspended in front of or just above the actors as they speak—while trying to keep the microphone, boom, and their shadows out of the camera’s field of capture. Depending on logistics and creative needs, the most prominent alternative to recording via a boom mic is to clip a small lavalier mic on the actor in such a way as to make it invisible to the camera (see here).

Regardless of which microphone is used, mic placement is crucial. Placing the mic directly in front of the mouth can pick up natural clicks and pops and breaths from the actor. A rule of thumb is to maneuver the mic between one to three feet in front of the actor, just above or below mouth level, but that is not an exact science, and each situation requires different placement choices. Remember: the distance between the mic and the speaking actor impacts the volume of what is being said. The further the distance, the lower the recording will turn out. If the person speaks softly, or if there is significant background noise, the mic needs to be closer to the actor’s mouth.

Keep in mind that the production mixer is there to get the desired creative result as clearly and efficiently as possible. Thus, he or she must speak up when there are situations that might interfere with this goal. For instance, if a character is speaking over an explosion or gunshot, dialogue may not record clearly. Therefore, the production mixer might ask the director if there is time to record wild lines as soon as the scene has been shot. That essentially means asking the actor to repeat the line right after the scene finishes, so that a clean recording will be preserved.

You won’t immediately master all these skills. It will be a gradual process to fully learn how to use the properties of sound to full advantage when recording dialogue, with some mistakes along the way. That said, none of the problems you encounter should be caused by a failure to have the best equipment you can access, good backup strategies, a solid knowledge of basic mic placement, and the know-how to properly use whatever recording device you have available.

Recording Sound Effects

Sound effects, by their nature, represent a particularly wide category but also a highly creative one. Depending on your skill level, resources, time, and creativity, you can potentially go anywhere to record sounds you think your postproduction team will need. You might take recording trips to sets and locations separate from principal photography and even to other locales. In fact, most industry professionals proclaim strongly that, when possible, you need to record in the real world. As Gary Rydstrom says, “That’s the discovery part, the cool part—you never know what you will find.” A simple recognition that unique sounds can be captured and used to good effect simply by being enterprising and open minded is important to your creative success. Indeed, Rydstrom emphatically insists that “any recording trip that does not include a surprise is not a good recording trip.”

Thus, Rydstrom’s mentor, Ben Burtt, famously recorded traffic on a Los Angeles freeway through long pipes, and later turned the resulting recordings into the humming sound of the “speeder” bikes in Star Wars. Your job when recording effects is to apply such initiative to your project. At the same time, though, you have a specific mission related to your particular story, limited time and resources, and a need to adhere to your story’s requirements.

As such, recording trips should be thoroughly and logically planned out. Your breakdown of the script and research into locations will cue you about where you need to go to record your sound effects—a train station to record a train, for example. Other ideas will emerge from your creativity—a junkyard, your own backyard, and so on. Pay attention to the section on Foley (see here) to get a clearer understanding on just how creative you can be in sound.

As you head into the field, you will be carrying similar equipment to what you used for production recording: a wide selection of mics; booms; a field mixer with a VU or peak meter (see here); a preamp, a compressor, and other specialized equipment when feasible (see here); recording media; quality headphones; cables; and helpful supplies, such as a notepad and Sharpies, spare batteries, a laptop or external hard drive for backup, and supplies to clean and repair your recorder. Be as diligent as possible about testing your equipment, checking settings, and having backup strategies—such preparations could spell the difference between success and disaster.

Beyond equipment, you might bring along props for experimental recording work—pipes, tubes, hammers, bells, and the like. You might also carry blankets, pads, and pillows in case you find yourself in a space where sound is too live and you need to deaden it somewhat.

Also, if possible, bring an assistant with you. Sound assistants are crucial on major projects, for loading, unloading, and setting up equipment; providing support and backup; pulling cables and placing mics; operating booms; and more. Even if you can’t hire someone, ask a fellow student or friend to help out.

Assistants are particularly helpful because simply recording sound is not enough. You are a data manager in the field. You must label tapes, cards, hard drives, or whatever media you bring; take care in your file-naming conventions; log sound takes with a sound report or sound-take number; and make sure you have backed up everything to other media before leaving the location.

Recording Levels

A big part of your responsibility when recording sound involves setting and controlling the recording volume. Virtually all modern sound recorders and cameras with audio capabilities will have similar audio controls, usually called the pot (short for potentiometer) or fader, with which you control the sound level, sometimes called gain.

Most modern digital recording devices also have peak meters—instruments that read the volume level—typically going from a negative number all the way up to 0 dB, which, ironically given the zero, represents the highest level the device can measure. The abbreviation dB stands for decibels, a unit for measuring the intensity of sound, and the marking dBFS represents decibels full scale—maximum peak levels for decibels on digital systems. Older analog devices may have volume-unit meters, or VU meters, which express the same idea of monitoring the signal but are not as precise—they provide the average sound level but do not indicate peak levels.

Either way, you generally want to record at the loudest possible level without going as far as zero—in other words, loud, but not too loud. Also, when feasible, maintain the same level all the way through the recording as much as possible. However you adjust things, try to be consistent on all tracks—do test recordings before rolling for real. Find a level that works, and stay there unless you have a good reason for changing it.

Also, some recording systems offer automatic level control. As the name suggests, these devices automatically control and maintain gain: boosting it when the signal is too low and lowering it when levels are too high. Be careful in using automated controls in any creative endeavor like filmmaking because you delete human judgment and creativity from the equation once you choose settings. Plus, some automatic systems do not handle sudden noise changes well, so if you are going to use automatic level control, test the system thoroughly. In any case, do not become overreliant on your meters for adjusting sound levels—there is no substitute for listening closely. In an action scene, for example, where dialogue, sound effects, and other noises might collide, you will have peaks and valleys, whispering and shouting. You need to strategize carefully and consider whether you should record at lower-than-typical levels as protection against level surges during such scenes.⁵

Other technologies audio professionals use to control recording levels include limiters, which are separate automated systems that activate if volume levels rise sharply, making them helpful in such scenarios as the action scene just described; compressors, which can, depending on the model, work with a recorder or microphone to compress the sound’s dynamic range if levels spike too high; and preamplifiers (preamps), which usually connect to a microphone to boost a low signal before that signal is sent to the recording device.

Microphones

Obviously, any sound recording requires some kind of microphone. Generally, you have two choices: using a built-in mic on your camera or, preferably, using an external mic that connects to your camera or audio recorder via a cable or wirelessly via a transmitter. The external mic option is often preferable because, in most situations, it provides better sound quality than most built-in mics.

Your mic will either capture a signal that is then directed to the camera’s onboard media—tape, solid-state card, or hard drive—or connect to an external recorder or mixer, a device that will give you the opportunity to adjust sound before recording it permanently to your storage media (see here for more on recording equipment). At a minimum, a good working knowledge of the basic concepts of transduction and polar patterns, and the different types of microphones that result from these concepts, will be useful, because that knowledge will help you make wise choices about which mics to use in different environments.

At the base level, microphones are transducers—devices that convert energy from one form to another. Mics capture sound waves—acoustical energy—and turn them into electrical energy as signals that can then be recorded. When sound waves hit a microphone’s diaphragm—the actual transducer—it vibrates. The device turns those vibrations into electrical energy. At the other end, the electrical energy is converted to an audio signal by the receiving device.

There are, however, methods of transduction besides using an actual diaphragm-style mic, and that is how we get different categories of microphones. Capacitor microphones, electrical condenser microphones, and others use different forms of transduction to send the signal. Dynamic condenser microphones are quite common in the movie world because they are generally rugged in the field. Condenser mics have an electrical capacitor built in to simulate a diaphragm; be aware, however, that because of this design, they do require their own power supply.

There are other important issues related to how microphones pick up, convert, and relay audio signals, including frequency (the rate at which a sound repeats), frequency response (how effective an audio device is in transmitting an audio signal after receiving it), amplitude (the maximum range of a signal when measured from a particular average), and decibel level. But for now, the key concept is the polar pattern, also called the pickup pattern. The mic’s polar pattern, based on its design, determines from which directions it can pick up sounds—in other words, how sensitive it is. This concept is commonly called, for obvious reasons, directionality.

Some mics are designed to capture sound from a broad-ranging area. Others are extremely sensitive and are designed to pick up only a narrowly defined range of sound, which is useful when you are trying to capture a specific sound in an area filled with background noise. Thus, like camera lenses, different mics have different uses. With that in mind, here’s a quick look at the most basic types of microphones—all nicknamed based on their polar pattern design.

Those are the basic categories of microphones based on pickup patterns, but the other key issue relating to mics involves their placement for recording purposes. We have discussed handheld and boom microphones, but as mentioned earlier, it’s frequently necessary to attach a microphone to a person or an object. The most common mic for placement on actors is the lavalier microphone, which gets its name from the fact that it can generally be attached to a person’s lapel, hidden from camera view. Lavaliers are small and are often used with wireless transmitters to make them easier to hide on a person. They are used to pick up the voice of single individuals and are therefore useful for television news, sports, documentaries, and reality shows. They can be designed with any polar pattern, but most lavaliers are omnidirectional or cardioid. Manufacturers offer a huge range of wireless microphones of all types and polar patterns.

Another category is the boundary microphone, sometimes called a pressure zone microphone. This is a small, flat mic that can be attached to a flat surface. Its purpose is usually to record multiple people or musical instruments when conditions don’t permit mics to be situated near each actor.

Recording Equipment

Along with a microphone, you need a safe and reliable way to record your sound. This typically involves the use of a digital recorder in combination with a field mixer—a portable battery-powered mixing device that allows the recordist to combine multiple mic signals and mix them into a single output signal in the field. The idea is to capture sound directly to your recorder if you are only recording a single audio source, or to take multiple-source audio signals and send them to the field mixer to combine before sending the signal on to the recorder.

You can simply record right to your camera’s source media or go from the field mixer to the camera if you do not have an external audio recorder. But either way, you need to have conceptual familiarity with capturing and mixing multiple channels of audio. Sound recorders can capture audio on all sorts of media these days, ranging from analog tape to digital hard drives, solid-state cards, or optical disks, such as CDs or DVDs. For decades, analog field recorders were used to capture sound on quarter-inch tape, and later digital audiotape (DAT), but the digital audio recorder has largely taken over today.

The current generation of digital recording technologies offers dozens of options, including small, handheld devices that provide rich sound at consumer-level costs. Such devices produce sound as digital files and save them to the recording media. You can also record to a laptop or desktop computer, iPad, or smartphone with a wide range of recording apps.

Keep in mind, however, that the world is awash in audio file formats, and many of them compress original data to make it more manageable. During your testing phase, you need to pick not only your recorder and recording media but also your file format and how much compression you can accept. The general rule of thumb is, if you have enough storage space, or enough media, you want to record with as little compression as possible. A good modern recorder will likely give you the option to record uncompressed or to choose which data compression scheme you prefer, such as the popular MP3 format used by consumers or BWF (Broadcast Wave Format), popular in film and television production. Compressed audio can sometimes work fine, but be careful when choosing a recorder to pick one that gives you options and is not limited to a low data rate.

You also need to thoroughly read your recorder’s manual and test it before you head into the field. Know what its limitations are and what its settings will permit you to do. Among the setting choices, you will need to make decisions about the sample rate and bit depth you prefer, the file structure and compression scheme you want, how to name your files, and so on. Sample rate refers to the rate at which the digital recorder “samples” the signal being recorded. Bit depth, as discussed in Chapter 6, is essentially the flip side of the sample rate, impacting a signal’s resolution rather than its recording level. With high-end equipment, you get many options in these areas. For now, you will likely be limited in what tools are accessible to you, but always choose the best sample rate and bit depth available. As a general rule, the higher the sample rate, the better quality your recording will be; keep in mind, however, that the sample rate options available to you may depend on the recording technology you are using, and that the higher the rate, the more data storage will be required. The same concept applies when you increase bit depth—you can improve quality and lower noise in the recording, but you increase the amount of data you need to process and store in the field by doing so.

As mentioned, take care to log everything—including timecode, if possible. Logging timecode means labeling data with the specific time that it was recorded, making it easier to synchronize sound to picture data later if sound and picture were recorded on separate devices. If you do not have timecode available, then slating the shot will be your method of manually creating a sync point to match up sound and picture.