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Digital TV / Digital Vs. Analog / Digital Sound

The days of vinyl are long gone. I'm not talking about the upholstery in your grandparent's sedan. Instead, I'm getting nostalgic about those old 78 RPMs spinning on the record player and the oh-so-careful lift of the needle. Stereophonic sound!

When CD's appeared on the market, most people were skeptical about the silver discs, but the sound was great. Digital audio recordings on CD have a wider frequency range, finer sampling, and they won't wear down with age (it stays perfect until something like a scratch damages the data). Almost everyone can hear an obvious improvement. Eventually they have taken over the commercial music industry, but television is still low-range analog.

Dolby Digital Sound

Taking the next logical step, HDTV will broadcast sound using the Dolby Digital/AC-3 audio encoding system. It's the same digital sound used in most movie theaters, DVDs, and many home theater systems since the early 1990's. It can include up to 5.1 channels of sound: three in front (left, center, and right), two in back (left and right), and a subwoofer bass for a sound you can feel (that's the .1 channel). Sound on digital TV will be "CD quality" with a range of frequencies lower and higher than most of us can even hear.

Ghosts in the Machine[next]


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