Ray Dolby, the engineer who founded Dolby Laboratories and whose innovations ushered in the modern era of sound for filmed entertainment, died Thursday in San Francisco. He was 80.

He had been suffering from Alzheimer’s Disease and was diagnosed in July with leukemia.

Dolby pioneered the noise-reducing and surround sound technology used throughout the entertainment industry.

Sound pros in Hollywood hailed Ray Dolby’s inventions as the key to a new era of motion picture sound.

“‘Star Wars’ changed sound forever. That was the pivotal moment in movie sound,” said Michael Minkler, lead re-recording mixer at Todd-AO Studios. “In 1977, when we mixed ‘Star Wars,’ there’s literally no way a movie of that magnitude was ever going to make it without Dolby Noise Reduction.” At times, said Minkler, literally hundreds of tracks were playing for that picture — but without hundreds of tracks’ worth of the hiss and rumble that all recording media had before Dolby came along.

“He was so driven in creating a cleaner, quieter track,” Minkler said. “If Ray Dolby’s inventions had never happened, (the mix for ‘Star Wars’) could not have happened.”

“Though he was an engineer at heart, my father’s achievements in technology grew out of a love of music and the arts,” said his son Tom Dolby, a filmmaker, and novelist. “He brought his appreciation of the artistic process to all of his work in film and audio recording.”

Dolby’s innovations established worldwide standards for sound, and his company became watchdog of sound quality for filmed entertainment. Wylie Stateman, co-founder of Soundelux, said the standards Dolby created made possible all of modern movie sound design.

“Dolby didn’t just create the playing field, he flattened it. Meaning we were free to explore to our wildest dreams but safe in knowing there were standards,” Stateman said. “You weren’t designing sound for one theater, you were designing sound for every theater on Earth.”

He also revolutionized the theatergoing experience, Stateman said. “He first started with Dolby Surround Sound and was the first to sort of standardize all that so any filmmaker could work in a format that was accepted worldwide. He created a worldwide standard of quality and form that really improved the whole sound experience for the general audience in films across the world.”

Tom McCarthy, sound topper at Sony Pictures, said, “Ray’s innovative mind and company have enhanced the moviegoing experience for audiences around the world. Ray will truly be missed. His vision and insight into the world of sound is legendary. He leaves behind a company that is integral to the moviemaking process and a memory of a man who took sound to new limits throughout his career.”

Dolby and his company were admired — and frequently honored—for their service to the industry. Founded in 1965, Dolby Laboratories has received 10 Academy Awards and 13 Emmys. Dolby holds more than 50 U.S. patents. Among his many honors, he personally received the National Medal of Technology from President Clinton in 1997; the Order of Officer of the British Empire from Queen Elizabeth II in 1987; an Oscar statuette (1989) and an Academy Plaque; several Emmys; and a Grammy.

He was a member of the National Inventors Hall of Fame and the Royal Academy of Engineers.

Dolby was known for his dedication to his work, not the bottom line. “I was never a gold-digger, or an Oscar-digger, or anything like that,” he once said. “I just had an instinct about the right sort of things that should be done in my business.”

Born in Portland, Oregon, he and his family eventually moved to the San Francisco Peninsula.

He started out working on audio and instrumentation projects at Ampex Corp., leading the development of the electronic aspects of the Ampex videotape recording system, and graduated from Stanford with a BS degree in electrical engineering. He was awarded a Marshall Scholarship and a National Science Foundation graduate fellowship, and left Ampex for further study at Cambridge U. in England.

In 1960, he became the first American to be named a Fellow at Pembroke College, and he received a PhD in physics from Cambridge in 1961. While at Cambridge he met his wife, Dagmar, and also served as a consultant to the United Kingdom Atomic Energy Authority.

Dolby became a United Nations adviser in India in 1963, then returned to England in 1965 and founded Dolby Laboratories in London. In 1976, he moved the company to San Francisco.

In 2012 the former Kodak Theater, home of the Oscars, was renamed the Dolby Theater, and its ballroom, which hosts the post-ceremony Governors Ball, was renamed the Ray Dolby ballroom. Sound pros still marvel that such an honor went to one of their own.

He is survived by his wife of 47 years, Dagmar; his sons, Tom and David; and four grandchildren.

Donations may be made to the Alzheimer’s Assn., 1060 La Avenida Street, Mountain View, CA 94043, or the Brain Health Center, c/o CPMC Foundation, 45 Castro Street, San Francisco, CA 94117.

A celebration of his life will be held at a later date.