An Inside Look at Surround Sound Formats

Despite the heavy emphasis on video over the past 15 years, the evolutions of home audio and video have actually taken nearly identical paths.

Looking back on the home A/V market in the mid 1990s the industry began a transition away from the VCR and its low-resolution video and Dolby Pro Logic audio technologies into the DVD optical disc format.

As everyone knows the DVD format offered consumers an improved picture with 480 lines of resolution and progressive deinterlacing options. It also offered a choice of audio formats that included standard PCM stereo, Pro Logic and discrete multichannel DTS and Dolby Digital.

As the decade of the 1990s drew to a close the video category moved onto high-definition (HD) video, while the audio market experimented with the higher resolution Super Audio CD (SACD) and DVD-Audio formats (DVD-A).

More recently the A/V market has fully adopted HD in the form of the Blu-ray disc format. Along with the HD 1080 picture quality of Blu-ray, the format also offers the lossless audio formats DTS-HD Master Audio and Dolby TrueHD. These formats matched the performance of their video counterparts by providing consumers uncompressed audio at levels up to 24-bit/192kHz for 5.1 and uncompressed audio for 7.1 systems.

Music and Electronics Industries Embrace Lossless Sound
Back before the Blu-ray format was established as a quality form of home entertainment, recording and mixing engineers and electronics manufacturers both quickly adopted the potential of lossless multichannel audio.

Now with consumers, recording engineers and CE manufacturers all supporting lossless audio, the technologies are almost taken for granted because they’ve been so widely accepted.

“Audio professionals have embraced DTS-HD Master Audio because it offers high-quality audio and is lossless. That means they don’t worry about what will happen to their recordings and final mixes, since DTS-HD MA delivers precisely what they created--bit for bit exact. Moving one step down the line, DTS tools are intuitive and easily accessible for professionals at any level,” says Fred Maher, audio testing & mixing/mastering specialist for DTS, Inc. “As far as consumer electronics manufacturers go, we estimate more than 100 million households or closer to 120 million worldwide have Blu-ray playback capability/DTS decoding inclusive of BD standalone, PS3 and PC BD. Additionally, all of the major manufacturers have implemented DTS-HD Master Audio technology in some of their AVR models and the PC industry has started to adopt the technology.”

On the pro side of the transition Maher explains that it took the engineering community some time to adapt to DTS-HD Master Audio’s full potential, but once those mixing professionals got acclimated to the technology it actually simplified their jobs. “DTS Digital Surround is our legacy codec [it is a lossy format]... the one that put us on the map. Some engineers used to monitor their mixes in real time, through DTS’s encode/decode hardware to make sure that what they were hearing was what the end user/listener would hear,” he says. “The new technology actually simplifies the process for those professionals as they no longer need to go through the additional step and expense of listening to the output with encode/decode hardware. Instead [they] can just listen.”