Ray Dolby, the Engineer Who Revamped Sound Technology

Before his name became a brand and a household word, Ray Dolby was a pioneer in noise reduction technology. His innovations revolutionized the audio and entertainment industries.

Even today, the name Dolby is synonymous with multi-channel surround sound systems. The fact is that the American engineer and inventor revolutionized sound technology and much of what happens to improve the sound of entertainment can be traced back to his efforts.

Ray Dolby at work in his lab.
Ray Dolby at work in his lab.

Who was Ray Dolby?

Ray Dolby was born on June 18, 1933, in Portland, Oregon. A musician from a young age, he took a keen interest in sound and how it worked. He also developed a fondness for movies and photography. On meeting Alex Poniatoff, founder of tape-recording company Ampex, Dolby soon had his first part-time job and began developing a greater understanding of audio technology.

Then, on leaving school, he studied electrical engineering at Stanford University and went on to receive a PhD in Physics from Cambridge University. During his time studying, Dolby was already working on prototypes for videotape recorder technologies at Ampex.

After he finished his studies, Dolby traveled to India as part of a United Nations team sent to set up a scientific instrumentation lab. It was there that Dolby encountered the problem of tape hiss while recording sitar music and he dreamed up the idea for noise reduction on audio tape recordings.

That very same year, 1965, motivated by the problem, he returned to England and founded the company Dolby Laboratories to look for a solution.

What Technology Did Ray Dolby Create?

Dolby is best known for his noise reduction system, Dolby NR, which was developed at Dolby Laboratories in 1965. The Dolby A noise reduction system employs electronic circuitry devised to reduce tape hiss and other noise inherent in analog audio tape recording and playback.

The process involves passing sound through an encoder as it is recorded and then playing it back through a decoder. The circuitry is amplitude-sensitive and pre-emphasises high frequencies before they are recorded in order to make them larger than the competing tape hiss noise.

When it is played back, a de-emphasis circuit restores the high frequencies to their proper balance. The result is the reduction of background noise with no adverse side effects, creating a crisp, clear, true sound for the listener.

After this, further noise reduction systems were developed. Dolby B, C and S were designed for the consumer market and all worked by compounding or compressing the dynamic range of sound during recording and expanding it during playback.

Dolby moved his company to San Francisco in 1967 and added manufacturing and research facilities. He then focused on developing technology for film production and other industries, including the Dolby Digital Surround Sound system.

A Dolby sound processor.
A Dolby sound processor.

In more recent years, Dolby Labs has developed digital technologies, including home theater systems, digital music file transmission systems and sound technologies for gaming. While Ray Dolby retired in 2009 to focus on philanthropy and sadly passed away in 2013, his technology still lies at the heart of these modern audio systems.

Dolby Revolutionizes the Audio World

The release of Dolby B in 1968 coincided with the first car radio cassette deck and the walkman, thereby contributing to the popularization of the compact cassette. When Advent designed one of the first cassette tapes for high fidelity, noise reduction was one way to fix the problems of background noise.

Once the original reel-to-reel high fidelity tape recorders were replaced by cassette decks for home use, the Dolby B became widely accepted.

Decca Records first used the Dolby system and by 1967 major record labels, including RCA and MCA, were also using it. It wasn’t long before the Dolby name was known throughout the recording industry.

The Dolby cinema in Barcelona, Spain.
The Dolby cinema in Barcelona, Spain.

Then in 1971, the first movie was released with Dolby sound, revolutionizing the cinema industry. The music was rendered more enjoyable and set the trend for what was to follow. In 1976, movie audiences experienced Dolby Stereo with four channels using magnetic technology.

It was Dolby’s clever use of matrix decoding technology that gave cinemas a way to generate surround sound on stereo systems from the same optical print on which the film was recorded.

Ray Dolby’s Greatest Achievements

Ray Dolby was never satisfied with a sound experience that wasn’t realistic, exciting and enjoyable and thanks to him, we get to enjoy these qualities throughout the film and music industry today, both at the theater and at home.

Ray Dolby (left) is inducted into the National Inventors Hall of Fame. NIHF president Rick Nydegger (center); United States Patent Office's Anne Chasser (right).
Ray Dolby (left) is inducted into the National Inventors Hall of Fame. NIHF president Rick Nydegger (center);
United States Patent Office's Anne Chasser (right).

While his greatest achievements were clearly his sound systems, he also has Emmys, Grammys, Oscars and a posthumous star on the Hollywood Walk of Fame to his name.

During his lifetime, Dolby earned more than 50 US patents and his company remains a place where scientists and engineers revel in pushing the limits of sight and sound for all of us to enjoy.

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