Linear anger at Dolby volte face1 February 2007
Dolby’s recently announced consumer-side loudness control is a retrograde development at best, reckons Linear Acoustic President, Tim Carroll. At worst, he argues, abandoning a decade’s worth of hard work is a tragic mistake.
The recent announcement by Dolby Laboratories of a new technology to address TV audio loudness issues has been greeted with a decidedly mixed reaction from the broadcast and post community. Linear Acoustic president Tim Carroll, an acknowledged expert in multichannel audio, considers the proposed technology, known as Dolby Volume and introduced at the recent CES Convention in Las Vegas, to be a step backwards in the delivery of high-quality soundtracks as producers intended them to be heard.
“We have a well-accepted, standardised technique in place using Dolby Digital (AC-3) which, via its built-in metadata system, can solve a leading issue for consumers: inconsistent volume across channels and programmes,” Carroll said. “I am wary of claims that systems lacking metadata suddenly require the addition of an uncontrollable single-ended process that affects all audio, thereby ‘fixing’ both annoyingly loud commercials and artistically loud scenes in programmes. It is impossible to control loudness in this way without, to some degree, affecting all programs. Further, the fact that it relies on consumer intervention will have predictably variable results – consider how many VCRs still flash 12:00!
“Dolby has always taken the respectable, albeit difficult position of protecting the original audio from being changed, relying instead on the harder path of metadata-guided loudness control. Consumer-side loudness processing has been available from others for several years, but has always met with strong opposition from Dolby.
“Certainly everyone is familiar with loudness issues, and evidence shows that through metadata and tools like its LM100, Dolby was making substantial progress,” Carroll continued. “Effectively abandoning over a decade of hard work is a tragic mistake on Dolby’s part. Put simply, if loudness is now controlled by the consumer’s receiver, broadcasters and post houses will have less need to be concerned with metadata or purchase a level meter or processing system.”
A major problem, Carroll predicts, is that not every TV set will contain this proposed technology. “As a result, to protect consumers that do not possess Dolby Volume”loudness control will need to be done upstream,” he said. “My best guess is that it will not make broadcasters and content producers work harder to author metadata, but exactly the reverse. Why will these professionals go through this effort if the TV set takes away control and sets playback levels? They will simply rely on effective but permanent loudness control at the TV station, much the same as in analogue broadcasting.
“I still firmly believe in the effectiveness of metadata when it is used correctly,” Carroll concluded. “Now that products from other companies finally can include metadata, Linear Acoustic will unveil the next generation of broadcast audio processing and transmission products at NAB2007, showing that the integrity of the original audio can be protected and loudness issues solved simultaneously, supporting the original Dolby vision for digital television audio.”