Backdraft movie poster, 1991Back in 1991, Skywalker Sound Director of Engineering Tom Scott needed to conquer space and time. He wanted movie director Ron Howard to mix his movie Backdraft at the LucasArts ranch in Northern California. But Howard was already at work on the set for his next movie, Far and Away, 400 miles away in Southern California.

To solve the problem, Scott and his colleagues devised a way to use Dolby audio equipment and the then-new fiber optic phone lines to transmit images and sound around the world nearly flawlessly.

Named Dolby® Fax™, the technology sounds like an artifact of tech history, surely superseded by the Internet and high-speed data connections. In fact, though, Dolby Fax is still in use today in producing TV shows like The Walking Dead, Vikings, The Borgias, and Vampire Diaries and movies like After Earth (2013).

For the early 1990s, before the days of broadband and telecommuting, Scott’s proposal to Ron Howard was audacious: they could prepare the audio for Backdraft on 35 mm sprocketed film during the day at the LucasArts ranch near San Francisco. At 5:00 p.m. each day, they would send the playback data over phone lines for Howard to review at Skywalker Sound South in Santa Monica. The audio team would make small changes as they spoke with Howard over the phone and save the more complicated fixes for the next morning, Scott told an audience of Dolby employees in San Francisco recently.

Scott’s team used the Dolby DP501 Digital Audio Encoder up north to compress the analog movie sound for digital transmission and the Dolby DP502 Digital Audio Decoder to decompress the sound files for playback. “The reliability of this thing was terrific,” said Scott of Dolby Fax.

“There’s a Dolby device talking to another Dolby device, and you’re sending a high-quality digital sound mix over a link that is traveling via synchronous data. … Synchronous data is in lockstep: it has a clock that determines where every little bit is supposed to be, so there are no errors and there’s very little jitter because telephone lines are tied back to the National Bureau of Standards, a very beautiful connection.”

The process worked smoothly for Backdraft, and in 1993, Scott and colleagues Tom Kobayashi and David Gustafson left Skywalker to further develop Entertainment Digital Network—ednet for short—to market the new technology. (George Lucas had passed on developing the technology within Skywalker.)

Dolby Fax was an essential part of producing the biggest hit of Frank Sinatra’s career. Grammy® award-winning producer Phil Ramone, known as “the Pope of Pop,” wanted to record Sinatra singing with 13 performers all over the world.

But Sinatra, 78, didn’t want to travel all over the world. So the crooner recorded his parts at Capitol Records in Los Angeles. Then Ramone used Dolby Fax to transmit the recordings to Aretha Franklin in a recording studio in Detroit, Tony Bennett in New York City, Charles Aznavour in London, Bono in Ireland, Liza Minelli in Brazil, and so on.

Frank Sinatra, "Duets" (1993)The resulting album, Duets (1993), sold over 3 million copies in the United States, making it the Chairman of the Board’s only triple platinum record.

“That was a huge success,” Scott said, “and gave us a tremendous kick-start.”

“This new technology changes the way artists record music,” producer Ramone told a New York Times reporter at the time. “And when you hear how wonderful it sounds, there is absolutely no question about its quality.”

Currently Vice President of Technology at ednet, now a division of Onstream Media Corp., Scott said that the advantages of long-distance recording quickly caught on, not least for the savings in time and travel. Famously reclusive singer Barbra Streisand asked Scott to set her up at home in 1997. “We could connect Dolby Fax there to her beautiful stereo. She could just hit the Aux button and be on,” he said. “She supervised an album mix by a lot of different producers around the country, but she never had to leave her Malibu home.”

A few years ago, Dolby announced it would stop making the audio processing equipment Dolby Fax uses. So ednet bought up a stockpile. “Dolby Faxes are perking along just as well as they did 20 years ago,” Scott told the audience at Dolby headquarters. “You should all be very proud that your company makes something that lasts this long and is this robust.”

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