Remember when you used to get your school grades on a punch card? The great Digital Deity was lurking in the shadows even then. As pretty much everyone who uses a telephone knows, the world has been boiled down to a series of ones and zeros. And consumer electronics is certainly no exception.
The compact disc player was introduced in the U.S. in 1982, and that set the precedent for a whole new digital foundation: not just for music, but for video as well. Of course the opposite of digital in CE-Speak is Analog. Analog is derived from the term analogous, which loosely translated means kinda, sorta, but not really. An analog signal is simply a representation of the actual signal.
In audio, the name of the game is to take an acoustical signal, which you can hear, then translate it into an electrical signal, which can be stored. Then the electrical signal is translated back into an acoustical, which you can hear. This magic act is not done with smoke and mirrors, but rather with a magnet and a coil. You see, when a magnet and a coil interact, they produce an electrical charge. A microphone is merely a magnet and a coil interacting-when sound waves are picked up. The sound waves are translated into an electrical signal and then sent to a tape recorder. An analog tape recorder stores a representation of that signal by changing the polarity of the magnetic particles on the tape. And a phonograph needle reads that representation on vinyl groove. No matter how precise your analog equipment, the accuracy of the reproduction is only going to be so good. That’s because there are some problems inherent in analog, which cause distortion-and there’s almost nothing you can do about it. Digital is totally different. Digital uses a series of ones and zeros to store sound waves, and depending upon the length of the digital “word” created, the more accurate the representation. Digital captures the acoustical signal by “sampling” the sound wave at many different places at a certain rate. The more places sampled along the wave, and the faster the sampling is done, the more information is garnered. The more information transmitted, the more realistic the sound, and the lower the level of distortion.
Music for compact discs is sampled 16 places along the sound wave at 44,100 times per second. The technical way to say this is that it has 16-bit Quantization, and a Sampling Rate of 44.1 kHz. This system was agreed upon by a bunch of industry folk, because at that time, it was head and shoulders above anything we had ever heard. And truth be told, not a lot of average listeners could tell the difference between that system (called the Red Book Standard), and something better. That was then, circa 1982: a century ago in Digital Dog Years. Think about your computer and how obsolete it is, even if you just bought it yesterday.
Faster processors, cheaper memory, and better data-compression algorithms have increased the amount of data that can be processed and stored. Translation: If your A/V system doesn’t make you feel like you’re there in the show, you didn’t get your money’s worth.
Dolby Digital, DTS, and ATRAC, and MPEG-2
Before we delve into the new digital products on the horizon, let’s take a step back and discuss the foundation upon which many of these products are based.
Dolby Digital is also called AC-3 and is the newest surround sound format by the surround sound leader. It delivers five discrete channels of sound – stereo main speakers, a center dialogue channel, and stereo rear speakers. It also delivers a sixth channel, which only contains low bass information and is meant to go directly into a powered subwoofer so you can feel the sound as well as hear it.
All of the new digital inventions feature Dolby Digital sound-it has become the standard for the new era. But as is the spirit of American capitalism, there is a competitor to Dolby Digital, Digital Theater Systems or DTS. DTS is partially funded by Steven Spielberg and is very popular among movie theaters across the U.S. DTS executives also claim that it delivers better sound especially for pure music listening as opposed to surround sound for movies.
Both systems use an encode/decode process, which means that you have to have a movie or song, encoded in Dolby Digital or DTS for it to work. Neither will work on non-encoded software, it will just sound “normal.” Which one survives is anyone’s guess at this point (or maybe they both will). ATRAC is an audio data compression/reduction system that is used in the recordable MiniDisc, which will replace your cassette deck. It allows a great deal of audio information to be stored on a 2.5-inch disc. MPEG-2 is video compression system that allows a great deal of video information to be stored on a 5.25-inch DVD, as well as to be broadcasted through the air and received on your Digital Satellite System. It will also be the data compression format utilized by the new Digital Television system.
Video DVD
A replacement for your VCR is here and selling quite well. Although it doesn’t record and might not for a while, DVD delivers a picture that is more than twice as good. It uses Dolby Digital for its surround sound, and MPEG-2 to store the video signal. DVD has massive storage ability and can hold 4.7 gigabytes per layer, which is roughly the equivalent of 7 compact discs or 3,400 floppy disks. Most DVDs will be dual-layer, yielding 8.5 gigabytes. And it’s also possible to produce a double-layer, dual-sided DVD, which can a store a whopping 17 gigs, an equivalent to 11,800 floppy disks!
All of this translates into up to eight hours of continuous full-motion video on a single DVD. The beauty of DVD is not only the almost 500 lines of resolution (as compared to standard VHS’ 240 lines), it is also the fact that it has the room to add really cool stuff for the movie lover. Many movies on DVD feature a director’s cut with scenes that were nixed by the studio, as well as commentary by the director, and biographies of the stars.
As of this issue, there are over 1,000 titles available on DVD with dozens more released monthly. Because of its gargantuan storage capacity, DVD has also become popular with the computer set, but an affordable, recordable DVD player for movies may not be around for a couple more years.
Audio DVD
It’s not time to start selling your CDs yet, but some audio engineers have recognized the storage capability of DVD and have been playing with the ramifications for sound. There is no clear cut standard at this point, but we are moving toward a 6-channel audio format that will pretty much knock the socks off of the existing Red Book compact disc. The public may host a mass lynching when they find out that Audio DVD is not compatible with existing Video DVD players. Down the road a new type of DVD player will become available called the Universal DVD player which purportedly will play Video, Audio, and perhaps computer DVDs as well. More on Audio DVD as it develops.
DSS with Dolby Digital
Recently DirecTV, the major player in Digital Satellite Systems announced that it would begin broadcasting with Dolby Digital sound. This means that you can pick up the same perfect digital surround sound through the air that you can get off of a DVD. And if you have a Dolby Digital surround sound receiver, you can enjoy movies in their entire sonic splendor. DSS delivers a picture that is about 420 lines of resolution and pretty close to the level of DVD. And here’s a segue: DirecTV has also indicated that they are fixin’ to start broadcasting in HDTV as well.
Digital Television
You may have heard about it or read about it: it’s DTV-the latest conspiracy by the consumer electronics industry to sell you something new and expensive. Digital Television does in fact work, and thousands of lucky people have already experienced it at various industry conventions. The most impressive thing is what’s called HDTV or High Definition Television, which utilizes a 1080i or 720p format. 1080i means that there are 1,080 pixels within a square inch of the TV’s screen. It is not really comparable to the Lines of Resolution terminology we have heretofore been bantering around. But suffice it to say, that it is about 4-5 times better than anything you’ve seen so far. The “I” stands for Interlace, which means that the picture is produced in halves and the halves are interlaced quickly on top of one another to form a whole.
This process is done so quickly that you can’t tell. Interlace is the method used by current TV sets. The “P” in 720p stands for Progressive, which means that the entire picture is produced at once. This is the method used by computer monitors. Progressive is generally regarded as a better picture, but there isn’t enough bandwidth to do both, hence the two formats which will rival each other.
One of the good things about the way that DTV is being handled, is that there are currently eighteen different DTV formats-all of which will be compatible with the new sets. So whatever Digital TV set you buy, chances are good that you’ll be able to receive all eighteen. Some formats will be HDTV and some will be Standard Definition Television. STDV is slightly better than today’s DVD picture. The reason for SDTV is that it takes about as much bandwidth to broadcast one channel of HDTV, as it does for five channels of SDTV. As usual it becomes that age-old dispute between quantity and quality. Broadcasters are still deciding on which they like better.
In fact, there are a lot of things that broadcasters must get together before the FCC-mandated start date of 2006. Stations have to make major investments in digital broadcasting equipment. Digital broadcast towers have to be erected. And the way that the signal is to be received by the customer still has to be worked out. The original plan was to broadcast the signal terrestrially, which means through the air like in the good old pre-cable days. The problem is that well over half of all Americans get their programs through cable. And there are so many different cable systems that getting them all onto a single digital standard is tantamount to affecting world peace.
Plus there are rumors that the terrestrial system is fraught with peril as well: signals are having problems getting around aluminum siding and among other obstacles such as leaves (i.e. the things that grow on trees). So if you buy a Digital Television set in the winter, it might be totally useless by spring. By the way, when they come out, Digital TV sets are expected to cost between $7,000-$10,000. You guessed it: More on DTV as it develops.
MiniDisc
The gurus at Sony have a vision: Stick your CDs in a mega-storage CD changer and make copies on MD to take on the road. The theory is that CDs are not exactly the all-impervious medium they were originally touted to be and they get damaged when they’re taken out on the road.
Sony is leading the charge by selling CD changers that accommodate 100, 200, or more CDs. You just stick all of your discs in at once and then leave them there for life (real discophiles can even daisy chain them together). Most mega-storage changers allow you to program the disc’s artist, title and track info so that information appears when the disc is played, and you won’t forget what’s where.
If you want to take the music with you-in your car or for a jog-merely make a direct-to-digital copy on a recordable MiniDisc and you’re good to go. MD’s have a protective caddie (like a computer floppy disk), so you can toss them around and no harm will be done. And MiniDisc recorders also allow for text edit, so you can annotate customized recordings.
Of course for every theory there is a counter-theory, and the folks at Philips feel as though the Compact Disc is quite firmly entrenched at this point. So other companies such as Marantz and Pioneer are investing heavily in recordable CD which can be played in any old CD player. Even though the price of a home recordable CD player has come down dramatically, it doesn’t keep the discs from getting scratched.
