A quartet of surround-sound technologies competed here at the NAB Radio 2004 convention for the attention of radio stations planning to convert to digital-broadcasting-based on the HD Radio format.
Although the surround solutions aren't likely to be compatible with one another, they will all be compatible with two-channel HD Radio receivers, which will play the surround broadcasts in two-channel form, their advocates say.
One of the surround technologies, SRS's matrixed Circle Surround II, was demonstrated at January's CES and has been tested and approved for use by HD Radio inventor iBiquity Digital. Home products with Circle Surround decoders are already available, and Circle Surround II encoders are available for sale to radio stations.
The other three technologies deliver five discrete channels, but they are nonetheless said to be backward-compatible with two-channel HD Radio receivers. Two of the technologies are from radio-station suppliers Telos and Neural, which previously demonstrated its technology with XM Satellite Radio service. The fourth technology, called HDC Surround, was developed jointly by Coding Technologies, a developer of audio compression technologies.
Although there might be room in the market for more than one surround solution, said iBiquity's marketing VP David Salemi, the “last thing” that radio stations want is “different solutions.” Should more than one solution come to market, however, Salemi said he doesn't expect a replay of the AM stereo debacle of the early to mid 1980s. Surround sound “is more of a feature of HD Radio,” Salemi said. “If there were two to three competing IBOC (in-band on-channel) contenders, that would be a disaster.”
“It's too early to tell” if iBiquity or the NRSC (National Radio Systems Committee) would test the systems for audio quality and compatibility with stereo-only receivers, Salemi said. He did say, however, that the three new systems, unlike Circle Surround II, “are not yet ready to go to market.” Demonstrations at the convention used PCs rather than prototype receivers to play back music, he noted.
However the technology competition shapes up, “surround sound will definitely be in HD Radio's future,” Salemi said. “If not in 2005, then certainly in 2006.”