Is There A Future for the MiniDisc?

 



 

 Introduced by Sony in 1992, the MiniDisc (MD) is an erasable, laser-optical format that employs a 2.5-inch disc housed in a protective caddy resembling a 3.5-inch computer diskette. MDs come in two types: premastered (prerecorded) and recordable (blank). Premastered MDs, recorded at music studios, can be played back virtually endlessly. However, they can't be recorded on--or over--like audiocasettes.

To record, a recordable MD must be used. The laser inside the recorder applies heat to the MD, demagnetizing the magnetic layer of the MD. The recorder then applies a magnetic field to the layer which corresponds exactly to the audio signals generated by the connected source. The north and south polarities equate to digital "1" and "0". This process also can be repeated a virtually endless number of times.

While compact discs store digitized audio data in linear PCM fashion, the MD uses a data-compression system to acquire either 60 or 74 minutes of stereo audio information. The system--nown as ATRAC--utilizes a psychoacoustic model to eliminate portions of the audio that are masked by other portion or otherwise deemed inaudible. This model has been widely used to encode both the audio (Dolby Digital) and video in DVDs and digital satellite broadcasts, in addition to the forthcoming digital television system.

MDs appeared to particularly well suited for portable applications (beside being small, it is inherently resistant to shock during playback) and is more flexible than CD-Rs/CD-RWs in terms of editing. In addition to being able to record up to 255 tracks (compared with 99 on a CD), the user can delete, combine, move, and divide tracks after they have been recorded. MDs also enable the user to label recordings with disc and song titles, artists' names, etc., for display during playback.

On the other hand, MDs fall far short of CDs in terms of marketplace penetration. Few prerecorded titles are available, and--because the format is not compatible with CDs and the number of people owning machines remains small--the opportunities for using them are severely limited.

Damned by audiophiles (who regard its compression system as an inferior form of digital storage) and little known by educators (who rarely seem to be in the vanguard of AV technology), the format has remained marginal since its inception. As the price of recordable CD equipment and blank discs continues to drop (as of 1998, both are already much cheaper than competing MD hardware and software), the future for MDs appears to be in considerable jeopardy.