Know Your Audio

Is 5.1 audio having a big impact on HD?

AMES, IOWA: Last year I finally broke down and purchased an HD set for my home. I hadn't really planned on the purchase but when my old Zenith 50-inch set died, my wife and I decided to make the investment. Now that the holidays are over, I have started looking at 5.1 audio systems.

As part of IPTV's effort to stay connected with our audience as we transition to DTV, we have established a DTV users group throughout our coverage area that for us is the entire State of Iowa and portions of the surrounding states. During our early experimental broadcast tests, these dedicated early adopters helped us confirm digital signal coverage and performance. Now, as more stations are on the air with HD content, we're seeing a second wave of consumers purchasing DTV sets, and our list of user is growing even larger. Over the last few months I have been trading e-mails with a number of these users about potential purchases for the holidays. High on their lists of DTV items to buy is surround sound to go with their new wide screen TV.

PRICE VS. KNOWLEDGE

Since Iowans look to us to educate them about all things digital, we need to understand what is out there and what they are dealing with. In the world of home electronics there are only seem to be two options for the consumer. There are the big super stores where the prices are low but the chances of finding knowledgeable help is slim. On the other hand there are the smaller, privately owned stores where the focus is more on customized support but the prices are often higher and selection more limited. For the early adopters, unless they were extremely familiar with the technologies available the smaller, high-end shops were their only option. However, at last year's CES and again at this year's show, home theater in a box options abound. They are priced for virtually any budget and sized for any room so they are no longer the domain of the high-end consumer.

In an effort to research this article as well as to get an idea of what is in the marketplace I called and visited a number of the stores in the Des Moines area to find out what was moving. There weren't any real surprises in the research as far as what was being purchased. All of the usual brand names are moving. The system types that are moving the fastest are the units that include an integrated DVD/CD player as part of the package and the price is in the $200 to $450 range.

From my limited and admittedly not totally scientific expertise, programming is what is driving this market. I'd love to say that IPTV HD program audio is the chief contributor but in truth it is not. So far as I can tell from talking with the users, they purchased their systems to take advantage of the surround sound offered on DVDs and by accident they have discovered that some sports also use surround sound to enhance the game. The NFL coverage in HD has been a real win and oddly enough, Fox, which was the most reluctant and last entry into the world of HD, seems to be the best at implementing 5.1 audio into its coverage. I have to admit from my own experience, Fox's technicians do put together the best sounding games and as an AFC fan, this is difficult for me. Another interesting fact that has come out of my conversations is that most of the people that commented on the quality of the audio and favored Fox did not notice any significant difference between the Fox 720p and the 1080i offerings from CBS even when flipping back and forth between two games.

The most frequent question I get asked by viewers regarding their surround sound systems involves the speaker placement. Ideally, the viewer is trying to replicate the experience of being at the theater and what makes that experience so memorable is that in that environment they feel like they are in the movie, not in the theater. When I layout a system initially, I assume a clean room with no obstructions to enable a basic design. Left and right front speakers are placed about two feet away from the screen and slightly in front of the screen. Center channel is mounted directly above the screen. If possible, they should be equal level and about at ear level at the primary listening position. The rear speakers are really not rear speakers; typically I place them on the side walls at the primary listening position, not on the back wall. Depending on speaker type, elevation of the rear speakers is a little more critical.

I've done layouts for people by asking them to send me the dimensions of the room they are setting up and sent them basic layout sketches. So far this has been pretty successful and has really helped our viewers get the most out of their investment.

Bill Hayes

Bill Hayes is the former director of engineering and technology for Iowa PBS and has been at the forefront of broadcast TV technology for more than 40 years. He’s a former president of IEEE’s Broadcast Technology Society, is a Partnership Board Member of the International Broadcasting Convention (IBC) and has contributed extensively to SMPTE and ATSC.  He is a recipient of Future's 2021 Tech Leadership Award and SMPTE Fellow.