The humble compact cassette, invented for office dictation by Philips Electronics Corp. in the early 1960s, has been about the biggest success story in recorded music.
It’s cheap, portable and recordable, and the world embraced it wholeheartedly from the beginning. Based on a larger cartridge RCA had designed for home recordists, which failed, the small cassette triumphed over 4-track, 8-track and even digital audio tape as well as Philips’ intended replacement, digital compact cassette.
But after an almost 40-year run, the compact cassette may have met its match. Marketers this year are going all out to push the MiniDisc, or MD, first shown by Sony in 1992 and now offered by at least seven makers.
Its proponents say the MD is to the CD what the cassette was to the LP: a highly portable, recordable medium.
But Bob Ankosko, an audio expert and executive editor of Stereo Review magazine, is a little wary of all the hype.
“MD is a wonderful format for audio recording enthusiasts who like to make their own compilations. It’s far superior to tape in terms of convenience, although the sound quality of a cassette made with Dolby S noise reduction can be excellent–some would even argue slightly better than MD.
“As to whether or not MD will succeed in this country–that depends on such factors as product availability, pricing and consumer predilections,” he said.
“The real question is,” Aknosko said, “how many people are making their own recordings these days? And of those who are into recording, how many will opt instead for recordable CD?”
The 2 1/2-inch MD resides inside a plastic caddie, very similar to the 3 1/2-inch computer floppy disk. Being digital, the MD eliminates nearly all of the noise and distortion of analog recordings, and being a laser-scanned disc, it allows near instantaneous random access like CD. Unlike CD, its small size and mandatory memory chips in all players more suitable for portable use.
An MD stores the same amount of sound as a CD, 74 minutes. Most important, it records.
If it’s so cool, why has it taken six years to catch on? Maybe because Sony at first didn’t really know what it had.
Early marketing campaigns make it seem that Sony saw MD as a version of CD.
The MD took off in the market about as fast as Howard Hughes’ fabled Spruce Goose. But after an initial flurry of interest, and portable models shown by a handful of manufacturers, MD faded into the background.
What kept the format alive was its marketing as a replacement for the tape cartridge machines used by radio stations. The format swept that market and drew rave reviews from its influential users.
A unique data structure explains much of MD’s success in the broadcast market. Like a computer disk, it uses a table of contents that, combined with memory chips for storing audio read, allows the laser to skip around the disc without interrupting the audio.
Thus, selections can be re-ordered, added or deleted without erasing and re-recording. The user simply presses a couple of buttons on the control panel. Every MD and every track on the MD can be electronically labeled.
The label scrolls across the player’s front panel display. (Although CDs can also be electronically labeled, recording companies only recently began implementing this feature.)
The first push for consumer use of MD came in Japan, where now it eclipses the cassette. Sales are rising in Europe as well.
Worldwide, 6 million people purchased mini disc players in 1997, according to Sony. At the Consumer Electronics Show in Las Vegas in January, Pioneer, JVC, Kenwood and Yamaha showed their first U.S. MD units. Denon and Sharp showed new models and Sony introduced nine new models, including the first home mini disc changer.
Notable among the new entries was a three-CD changer/MD recorder combination from JVC as well as a car stereo that can load a compact disc or a mini disc through the same slot, saving space on the dash. Sharp showed an even more intriguing application, the MD-X8 mini-system with an optional PCMCIA modem card, designed to record music from the Internet using Liquid Audio (a competitor of the more popular RealAudio) from a laptop computer.
Cadillac recently began offering MD unit as a replacement for the tape player in the 1998 Seville.
JVC, inventor of VHS and long known as Sony’s staunchest competitor, is making an American push for MD, too.
Grant Lansdell, JVC’s National Product Specialist, Consumer Audio Division, said, “MD has begun to hit that critical mass, which is so important when you’re talking about mass market, which is what we cater to.
He thinks MD will soon replace traditional cassettes.
“We live in a digital world now. It seems silly that we take all these digital originals and record them on an analog medium. I wouldn’t be surprised if we start looking at cassettes the way we started looking at LPs a couple of years ago at this time next year.”
2 1/2-INCH DISC SCREAMS TECHNOLOGY
MiniDisc records using magneto-optical technology that can erase and re-record up to one million times.
The beam of a small laser heats a tiny spot on the recording layer to almost 400 degrees, at which point a magnetic head on the other side of the disc, modulated by the input signal, flips the polarity (changes the reflectivity) of that spot on the recording layer, creating a binary 0 or 1.
Pre-recorded MDs are pressed almost exactly the same as CDs.
Storing 74 minutes of stereo sound on a 2 1/2-inch disc (with a capacity of 140 megabytes) requires substantial data compression. Sony uses a 5:1 compression scheme called ATRAC, or adaptive transform acoustic coding. The company says its system is based on the way the ear perceives sound and the masking effects of some frequencies at various levels over other frequencies.
Because of the high-data compression, data can be efficiently stored on memory chips. All mini discs must have at least three seconds of memory; most have 10 seconds. The disc feeds data to the buffer faster than the actual playback heard by the listener. So if the laser skips or mistracks from shock or vibration, it is inaudible
