A Brief History of Motion Pictures and Film Sound

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People have been creating sound for motion pictures for over a century. Though the technology of recording sound has inevitably changed over the years , it is interesting to note that much remains the same. As with many modern-day inventions , sound technology all started with Thomas Edison.

Thomas Edison's The Sneeze

My plan was to synchronize the camera and the phonograph so as to record sounds when the pictures were made, and reproduce the two in harmony . We had the first of the so-called "talking pictures" in our laboratory thirty years ago Thomas Edison 1925

The talking picture he was referring to is called The Sneeze . Edison (Figure 1.1) filmed Fred Ott, a man who worked in his Newark laboratory, sneezing and recorded the sound onto one of his sound discs. The film and the sound recording were then played back together to make one of the first audio/visual works ever created. The Sneeze is only a few seconds long, but the ideas demonstrated by it are the foundations of modern multimedia. Edison went on to create many more films and even built a special building that allowed sunlight to be controlled in a way that was conducive to filming . Throughout the early 1900s, other attempts were made to synchronize sound with motion pictures, but few of these attempts were very successful.

Figure 1.1. Thomas Edison with an original Kinetoscope, one of the first motion picture cameras .

Sound Technology in the 1920s

In 1922, The German inventors Josef Engl and Hans Vogt invented the Tri-Ergon process. This process was an optical audio recording made onto the film itself, allowing sound and movies to be played together. It was accomplished by using a photoelectric cell to transduce sound vibrations into light waves that could be printed onto the edge of the film in a photo-graphic process. When the film was replayed, another photoelectric cell read the light patterns off the film and output an electrical waveform that could be amplified and fed to speakers in the theater.

In 1926, the Fox Film Corporation developed another sound-on-film technique, called Movietone, and began making newsreels with sound. The launch of Charles Lindbergh's trans-Atlantic flight to Paris was one of the first Movietone Newsreels.

In the early 20s, Bell Laboratories developed a sound-on-disc system using 33 ¹ /3rpm discs called Vitaphone. Warner Brothers first used the technology in the release of the movie Don Juan . It was the first major release of a film that replaced the traditional orchestra with music from the Vitaphone system. However, there still was no dialogue in this movie.

Warner Brothers released the first "talkie," The Jazz Singer, in 1927 . No dialogue was written for the film, so its star, Al Jolson, improvised a few lines, and that marked the end of silent movies. Warner Brothers continued to push the boundaries of sound in film with the release in 1928 of Lights of New York , the first all-dialogue feature film. In that same year, Walt Disney created the entire soundtrack for Steamboat Willie in post-production, including dialogue, sound effects, and music.

The 1920s ushered in most of the technological innovations that shape the world of film sound to this day. All of the elements of the soundtrack were created, in some form, during that first decade of film sound. The tools have changed, but the basic goals of creating entertaining motion pictures have remained the same. Just think what Walt Disney might have done with Pro Tools!

Disney's Fantasia

Walt Disney continued his innovation in film and audio techniques with the landmark production of Fantasia. Starring Mickey Mouse (along with many other animated characters ), Fantasia choreographed animation to classical music. To facilitate a truly immersive experience, the Disney technicians came up with many new methods and equipment for recording sound. Multi-track recording was used for the first time to capture an orchestra and then overdub additional instruments, creating a many-layered soundtrack. John Volkmann, the recording engineer for Fantasia , used eight optical recorders to capture the orchestrasix machines recorded different sections of the orchestra, a distant microphone on the seventh and the eighth recorder captured a balanced mix of the whole orchestra. This method gave Volkmann the ability to recombine the levels of each section in the orchestra or even re-record or overdub them if need be. Later, a ninth click track was added as a guide for animators to follow. Cues could be given as to what action should be taking place, and the animators would have accurate timing down to each frame of film. The forty-two days it took to record the music for Fantasia used nearly half a million feet of sound film!

As there was no such thing as time code or electronic synchronization in the 1930s, a different, mechanical method was used to synchronize the nine optical recorders. The same sprockets that insert into the holes on the edges of film in order to keep it positioned and running at the correct speed could be linked mechanically between machines in order to synchronize them physically, as seen in the Moviola machine in Figure 1.2. Once the sound film has been placed on the machine and aligned to the sprockets, it would stay in sync with the other optical recorders connected to it. This way, many machines could be linked to create as large a tape machine as needed. This type of synchronization is still used in the film industry today, although digital technology such as Pro Tools is rapidly taking over.

Figure 1.2. A very early film-editing machine called a Moviola. This type of machine is still in use today, although it is rapidly being replaced by non-linear digital editing systems.

A special playback system called Fantasound was invented specifically for Fantasia . The system employed two projectors. The first projector had the visual images on it, as well as a mono mix of the entire soundtrack as a backup. The film in the second projector, which was mechanically synchronized to the first, was printed with four mono optical tracks similar to the modern stereo optical track shown in Figure 1.3. Track one had control information, in the form of various frequency tones and amplitudes that were used to modulate the volumes of certain speakers during the show. Tracks two, three, and four contained the audio for the screen left, screen right, and screen center speakers, respectively. In addition, there were three other sourcescalled house left, house right, and house centerplaced behind the audience. These channels were derived from the screen left and right channels and were modulated by the control track as well. Thus, the first surround-sound system was born.

Figure 1.3. A piece of modern film showing the stereo optical tracks at the edge of the film. Notice how holes in the film go over the sprockets, helping to align and synchronize the motion of the film through the projector.

As the optical recording process did not offer much in the way of dynamic range, each signal was recorded as hot as possible, in order to reduce the noise level during playback. To achieve the dynamics needed by the film's orchestra conductor, Leopold Stokowski, the control track was implemented to vary the output levels to each speaker in accordance with the dynamics specified using voltage-gain amplifiers . This was a very early form of noise reduction. Today, technology such as Dolby SR provides noise reduction in more sophisticated ways.

William Garity, chief engineer for Disney at the time Fantasia was being made, was charged with creating a device that would simulate motion of a sound source back and forth across the screen. He theorized that fading levels between two speakers would create the desired effect. With that in mind, he designed a three-way differential circuit that allowed mixing down to a three-track master. The device was dubbed "The Panpot." It required six people, conducted by Stokowski, to operate all the panpots and adjust the levels while mixing the film. Stokowski had all the level and pan markings in his score, and he conducted the mixdown session as a film scoring session would be done today. As the VU meter had not yet been invented, a special three- color oscilloscope was used to maintain the proper recording levels.

Fantasia 's 54-speaker system was so expensive that only two were ever installed in theaters, one in New York's Broadway Theater and the other in the Carthy Theater in Los Angeles, at a cost of $85,000 each. The premier showing of Fantasia , on November 13, 1940, did not use a complete Fantasound system. Because of certain technical factors, a live sound engineer mixed the surround speakers during the screening. The Fantasound system was used only during the final "Ave Maria" sequence, and, for the first time, an audience was wrapped in 360-degree sound.

Due to the high cost of the Fantasound system, a smaller version was created that could travel around the country. It filled up half a freight car and weighed 15,000 pounds . It was called "Fantasia Road Show" and was used in only 14 theaters during the tour.

Fantasia has been re-released in various formats five times in the last 50 years. The first rerelease, in 1942, had a mono mix and was edited down by 43 minutes. In 1956, Fantasia was released in its entirety with a four-track magnetic format. In 1982, the soundtrack was re-recorded using a digital format. Although the fidelity of the 1982 recording is better, many fans of the movie considered the performance to be inferior to the original. So, in 1990, Disney restored both the picture and the soundtrack from the original masters. Since the optical recordings had been lost, the 1956 magnetic masters were used. Months were spent researching the original notes about the mix before Disney's Terry Porter was able to re-create the Fantasound mix for the modern 70mm Dolby six-channel surround format seen in theaters. This mix was also used to create the DVD master of the film.

Fantasia must be considered the most important film with respect to technical achievement in film sound. The innovations generated by its creation have fathered many of the techniques still used today in one form or another. It was an amazing accomplishment in animation, audio technology, and entertainment. Its high quality and creative value are still evident today.

NOTE

INNOVATIONS IN THE CREATION OF "FANTASIA"

Multi-track recording using synchronized optical recorders
Overdubbing of different parts by the orchestra
Click track used by conductor and animators to choreograph animation and audio mixdown
Multi-channel surround playback system
"Panpot" used to move sounds across the screen
Control track on film used to regenerate dynamics from optical recording i.e. , noise reduction
Use of oscilloscope to monitor recording levels predecessor to the VU meter.

Film Sound Formats

During the 1950s, film went through many different sound formats. The fear of losing audiences to television drove the film industry to adopt many new film formats using wider screens and more channels of audio to "wow" the viewer and stay competitive. The wide-screen formats of today are a direct result of this competition.

Following is a list of some of the many film formats used in the last 50 years, along with a brief description of related size and audio formats.

Cinerama (1952-1962). Three projectors and eight audio channels played back from a 35mm magnetic film audio tape with a seven-track headstack similar to the machine in Figure 1.4. Abandoned in 1963 due to high costs.

Figure 1.4. A 16mm, magnetic film, audio recorder. The Magnasync Moviola TP1710.
Cinemascope (1953-1967). Used anamorphic technique to achieve widescreen aspect ratio. Four-channel magnetic audio on the edge of the film, plus a mono optical track. This format was replaced by Panavision, with a stereo optical soundtrack with Dolby noise reduction.
Warnerphonic (1950s). Used another machine with sprocketed, magnetic film that was mechanically synchronized with the projector. Cinemascope's combined film made this format obsolete.
Todd-AO (1955-1992). Oklahoma was the first film released in the Todd-AO format. Invented by Michael Todd and the American Optical Company, it was printed on a 70mm piece of film with the audio occupying 5mm of that width. There are five speakers behind the screen, left, mid-left, center, mid-right, right, and a mono surround speaker behind the audience.
Dolby Stereo (1976-present). 35mm with two-track, matrix-encoded optical sound. Left, center, right, and mono surround.
Dolby Discrete Six-Track (1976-present). 70mm, 6-track magnetic master with left, mid-left, center, mid-right, right, and mono surround channels.
6-track magnetic master with left, center, right, mono surround, and a low-frequency effects channel (LFE).
Dolby "Split-Surround" Six-Track (1979-present). 6-track magnetic master with left, center, right, left surround, center surround, right surround, and LFE channels. The Big Daddy!
Dolby Digital (1992-present). 35mm, 5.1 optically encoded digital using AC-3 compression. Left, center, right, left surround, right surround, and the ".1" LFE channels.
DTS (1993-present). 35 or 70mm with accompanying proprietary CD that is synchronized to an optically encoded time code track on the film print. Includes Dolby Stereo compatible optical track as backup. Same 5.1 channel configuration as Dolby Digital.
SDDS (1993-present). 35mm optically encoded 7.1 with left, mid-left, center, mid-right, right, left surround, right surround, and LFE channels. The Big Mama!

NOTE

ANALOG BACKUP

Note that with any of the digital film audio formats there will usually be a Dolby Stereo analog track printed on the film as a backup, in case of any failure of the digital system and for compatibility with older theaters.

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A Brief History of Motion Pictures and Film Sound