A sound effect (or audio effect) is an artificially created or enhanced sound, or sound process used to emphasize artistic or other content of films, television shows, live performance, animation, video games, music, or other media.
In motion picture and television production, a sound effect is a sound recorded and presented to make a specific storytelling or creative point without the use of dialogue or music. Traditionally, in the twentieth century, they were created with Foley. The term often refers to a process applied to a recording, without necessarily referring to the recording itself. In professional motion picture and television production, dialogue, music, and sound effects recordings are treated as separate elements. Dialogue and music recordings are never referred to as sound effects, even though the processes applied to such as reverberation or flanging effects, often are called sound effects.
This area and sound design have been slowly merged since the late-twentieth century.
History
The term sound effect dates back to the early days of radio. In its Year Book 1931 the BBC published a major article about "The Use of Sound Effects". It considers sound effects deeply linked with broadcasting and states: "It would be a great mistake to think of them as analogous to punctuation marks and accents in print. They should never be inserted into a program already existing. The author of a broadcast play or broadcast construction ought to have used Sound Effects as bricks with which to build, treating them as of equal value with speech and music." It lists six "totally different primary genres of Sound Effect":
Realistic, confirmatory effect Realistic, evocative effect Symbolic, evocative effect Conventionalised effect Impressionistic effect Music as an effect
According to the author, "It is axiomatic that every Sound Effect, to whatever category it belongs, must register in the listener's mind instantaneously. If it fails to do so its presence could not be justified."
Film
In the context of motion pictures and television, sound effects refers to an entire hierarchy of sound elements, whose production encompasses many different disciplines, including: Hard sound effects are common sounds that appear on screen, such as door alarms, weapons firing, and cars driving by. Background (or BG) sound effects are sounds that do not explicitly synchronize with the picture, but indicate setting to the audience, such as forest sounds, the buzzing of fluorescent lights, and car interiors. The sound of people talking in the background is also considered a BG, but only if the speaker is unintelligible and the language is unrecognizable (this is known as walla). These background noises are also called ambience or atmos ("atmosphere"). Foley sound effects are sounds that synchronize on screen, and require the expertise of a Foley artist to record properly. Footsteps, the movement of hand props (e.g., a tea cup and saucer), and the rustling of cloth are common Foley units. Design sound effects are sounds that do not normally occur in nature, or are impossible to record in nature. These sounds are used to suggest futuristic technology in a science fiction film, or are used in a musical fashion to create an emotional mood.
Each of these sound effect categories is specialized, with sound editors known as specialists in an area of sound effects (e.g. a Car cutter or Guns cutter).
Foley is another method of adding sound effects. Foley is more of a technique for creating sound effects than a type of sound effect, but it is often used for creating the incidental real-world sounds that are very specific to what is going on onscreen, such as footsteps. With this technique, the action onscreen is essentially recreated to try to match it as closely as possible. If done correctly it is very hard for audiences to tell what sounds were added and what sounds were originally recorded (location sound).
In the early days of film and radio, Foley artists would add sounds in real time or pre-recorded sound effects would be played back from analog discs in real time (while watching the picture). Today, with effects held in digital format, it is easy to create any required sequence to be played in any desired timeline.
In the days of silent film, sound effects were added by the operator of a theater organ or photoplayer, both of which also supplied the soundtrack of the film. Theater organ sound effects are usually electric or electro-pneumatic, and activated by a button pressed with the hand or foot.
Photoplayer operators activate sound effects either by flipping switches on the machine or pulling cow-tail pull-strings, which hang above. Sounds like bells and drums are made mechanically, sirens and horns electronically. Due to its smaller size, a photoplayer usually has fewer special effects than a theater organ or less complex ones.
Notable early uses of sound effects in film
1897: A Canadian filmmaker premiered a silent film in which a blacksmith was placed outside of the audience view and made sounds to coincide with the visuals of a blacksmith in the film. Kelly Gang (1906): An Australian premiere of this film was accompanied by a symphony to add sound effects to the film as viewers watched it. 1914: Britain began producing sound effect devices that people could buy to play different sound effects for films at home. Blackmail (1929): Uses a woman's voice separate from the main actress on screen for screaming scenes. M (1931): Uses several street sounds such as car horns and the sounds of a ball to increase tension within the film. Spellbound (1945) Uses a Theremin to create one of the first instances of electronically produced sound effects.
Video games
The principles involved with modern video game sound effects (since the introduction of sample playback) are essentially the same as those of motion pictures. Typically a game project requires two jobs to be completed: sounds must be recorded or selected from a library and a sound engine must be programmed so that those sounds can be incorporated into the game's interactive environment.
In earlier computers and video game systems, sound effects were typically produced using sound synthesis. In modern systems, the increases in storage capacity and playback quality has allowed sampled sound to be used. The modern systems also frequently utilize positional audio, often with hardware acceleration, and real-time audio post-processing, which can also be tied to the 3D graphics development. Based on the internal state of the game, multiple different calculations can be made. This will allow for, for example, realistic sound dampening, echoes and Doppler effect.
Historically the simplicity of game environments reduced the required number of sounds needed, and thus only one or two people were directly responsible for the sound recording and design. As the video game business has grown and computer sound reproduction quality has increased, however, the team of sound designers dedicated to game projects has likewise grown and the demands placed on them may now approach those of mid-budget motion pictures.
Some pieces of music use sound effects that are made by a musical instrument or by other means. An early example is the 18th century Toy Symphony. Richard Wagner in the opera Das Rheingold (1869) lets a choir of anvils introduce the scene of the dwarfs who have to work in the mines, similar to the introduction of the dwarfs in the 1937 Disney movie Snow White. Klaus Doldingers soundtrack for the 1981 movie Das Boot includes a title score with a sonar sound to reflect the U-boat setting. John Barry integrated into the title song of Moonraker (1979) a sound representing the beep of a Sputnik like satellite.
Recording
The most realistic sound effects may originate from original sources; the closest sound to machine-gun fire could be an original recording of actual machine guns.
Despite this, real life and actual practice do not always coincide with theory. When recordings of real life do not sound realistic on playback, Foley and effects are used to create more convincing sounds. For example, the realistic sound of bacon frying can be the crumpling of cellophane, while rain may be recorded as salt falling on a piece of tin foil.
Less realistic sound effects are digitally synthesized or sampled and sequenced (the same recording played repeatedly using a sequencer). When the producer or content creator demands high-fidelity sound effects, the sound editor usually must augment his available library with new sound effects recorded in the field.
When the required sound effect is of a small subject, such as scissors cutting, cloth ripping, or footsteps, the sound effect is best recorded in a studio, under controlled conditions in a process known as Foley. Many sound effects cannot be recorded in a studio, such as explosions, gunfire, and automobile or aircraft maneuvers. These effects must be recorded by a professional audio engineer.
When such big sounds are required, the recordist will begin contacting professionals or technicians in the same way a producer may arrange a crew; if the recordist needs an explosion, they may contact a demolition company to see if any buildings are scheduled to be destroyed with explosives in the near future. If the recordist requires a volley of cannon fire, they may contact historical re-enactors or gun enthusiasts.
Depending on the effect, recordists may use several DAT, hard disk, or Nagra recorders and a large number of microphones. During a cannon- and musket-fire recording session for the 2003 film The Alamo, conducted by Jon Johnson and Charles Maynes, two to three DAT machines were used. One machine was stationed near the cannon itself, so it could record the actual firing. Another was stationed several hundred yards away, below the trajectory of the ball, to record the sound of the cannonball passing by. When the crew recorded musket fire, a set of microphones were arrayed close to the target (in this case a swine carcass) to record the musket-ball impacts.
A counter-example is the common technique for recording an automobile. For recording onboard car sounds (which include the car interiors), a three-microphone technique is common. Two microphones record the engine directly: one is taped to the underside of the hood, near the engine block. The second microphone is covered in a wind screen and tightly attached to the rear bumper, within an inch or so of the tailpipe. The third microphone, which is often a stereo microphone, is stationed inside the car to get the car interior.
Having all of these tracks at once gives a sound designer or audio engineer a great deal of control over how they want the car to sound. In order to make the car more ominous or low, they can mix in more of the tailpipe recording; if they want the car to sound like it is running full throttle, they can mix in more of the engine recording and reduce the interior perspective. In cartoons, a pencil being dragged down a washboard may be used to simulate the sound of a sputtering engine.
What is considered today to be the first recorded sound effect was of Big Ben striking 10:30, 10:45, and 11:00. It was recorded on a brown wax cylinder by technicians at Edison House in London on July 16, 1890. This recording is currently in the public domain.
Processing effects
As shown by the car example, using multiple DAT or multitrack recorders to create simultaneous recordings of the same subject allows sound editors or sound designers to shape a sound effect for realism or effect.
Once the sound effects are recorded or captured, they are usually loaded into a computer integrated with an audio non-linear editing system. This allows a sound editor or sound designer to heavily manipulate a sound to meet their needs.