Last week's Grammy Awards ceremony on CBS earned kudos from viewers as one of the best HD telecasts ever. It also signaled the beginning of the 5.1 surround sound era for CBS.
"We knew that our ability to not send 5.1 audio to our stations was a big missing element in HDTV," says CBS Vice President of Engineering and Technology Bob Seidel. "When we first started HD four years ago, the early-generation equipment didn't have the feature sets needed to go forward with 5.1."
But now that the equipment is in place, look for CBS to do much more 5.1 audio. The upcoming NCAA men's basketball tournament will be done in 5.1, and Seidel says that, beginning next fall, CBS will accept prime time programming with 5.1 audio. He says that CSI, CSI: Miami, The District
and The Agency
are already produced in 5.1, so those four programs are fairly good bets to be available to viewers in 5.1 next season.
"The fact that DVDs and theatrical movies are mixed in 5.1 has helped people already enjoy 5.1 surround sound," say Seidel. "So I think it's a very small step for viewers to realize the benefit of 5.1 for broadcast programming."
The move to 5.1 began about a year ago when Harris encoders capable of carrying 5.1 as well as other services CBS is interested in (such as closed captioning, V-chip, the broadcast flag, audio metadata and interactive services) became available. Four Harris HD encoders were installed in the CBS New York facility to distribute East and West Coast feeds to affiliates. In December, the network put integrated satellite receivers in the 25 of its 131 stations that have DTV signals. Those 22 markets carried the Grammy's 5.1 audio signal. Dolby E encoders and decoders were also used.
Getting 5.1 capability to the other 106 stations is a priority for CBS, and the network will be providing the stations with two integrated receiver units. It's up to the station to provide Dolby E DP572 Dolby E decoders (one for each receiver) and the DP569 Dolby digital encoder. Dolby estimates that more than 175 TV stations in the U.S. are capable of 5.1 surround sound transmission. The cost of the gear required is less than $10,000.
Sunday's telecast involved the use of a number of production vehicles. The video side was handled by All-Mobile Video's 53-foot Resolution truck. Seventeen cameras were used on the shoot, including Sony HDC-700 HD studio cameras and HDC-750 portable cameras, all outfitted with Fujinon lenses. The production switcher is a Sony MBS-8000 with Tektronix, Telex, and Leitch gear also being used.
That truck's Sony Oxford console was tied to an AMS Neve Capricorn console in Effanel Production's 48-foot L7 Mobile Recording Studio, which handled the primary mix of the 5.1 HD and stereo SD feeds. The overall 5.1 balance of all the elements originated from Effanel's on-site recording unit.
"I was very pleased with the production, especially considering that it was a first attempt," says Effanel President Randy Ezratty, who was in the OSR unit working on its Yamaha DM2000 console as 5.1 sound designer/mixer. "I learned a lot, and it's only going to get better."
Ezratty says sync, bass management, philosophical direction and stereo compatibility were all issues until show time. Ezratty also used a Dolby DP570 multi-channel audio too so that he could hear what the 5.1 mix would sound like in other environments like stereo or mono. CBS and Dolby solved the technical issues while the National Academy of Recording Arts and Sciences (NARAS) pushed Ezratty to take a few chances with the 5.1 mix.
The audio and video signals from the trucks were sent back to CBS's network facility at 4:2:2 and via Dolby E. Dolby DP571 encoder. They were then decompressed, routed through the CBS plant, and compressed to be sent to the affiliates. When the station receives the encoded signal the DP572 decodes it, bringing the audio signal down to baseband and it then travels through most stations in that form.
"That signal is then encoded into Dolby digital with DP 569 before being sent over the air," says Rocky Graham, Dolby manager, DTV applications who also assisted with the Grammy telecast.
"Both audio signals were sent through a five-second delay so we could bleep out [obscenities]," says Seidel. "Keeping the two broadcasts synchronized within a frame so we could do that was a bit of a challenge."
The network facility also handled lip-syncing issues. Seidel says the network recommends that stations keep the audio embedded within the video signal so that there are no delays if it's run through a frame synchronizer or other device.
The feedback from HD viewers on message boards at the AVS Forum were highly laudatory, with some going as far as saying it was the best HD telecast ever. One thing is certain: It definitely made viewers feel they were at Madison Square Garden.
"We have a viewing room at CBS that is designed like a living room," says Seidel. "We were watching on the couch and would turn around when we heard a voice coming from the speaker behind us that was a person in the crowd at the Garden."
Eric Duke, president of All-Mobile Video, says the effort went well on his end as well. Seventeen cameras were used, with the SD version taken from a downconversion done with Sony downconverters. A separate SD switcher was then used for the production.
"For years, we've been working with the digital audio consoles, fighting with the bugs and people that didn't want them in the trucks because it was too complicated or risky," says Duke. "To see it all come together on Sunday night was a real charge for all the people that worked so hard to put it together."
