Mini disc: an editable disc with 'near CD' quality

Lee Chin (Editor: Scott Partridge)

Since the 1950s, music lovers have been using cassette tapes to record their favorite songs. But after the compact disc (CD) debuted in the 1980s, consumers started to feel the recorded quality of tapes from CDs was not good enough because tapes cannot present the exact sound quality of CDs. Now it’s the 1990s and there’s finally an effective way to record CDs – Mini Disc (MD). Mini Disc was first introduced by Sony in 1992 as a disc based digital audio system with a characteristic of 'near CD' in quality. It is only about half the size of a CD (64-mm in diameter), but it can hold just as much music (up to 74 minutes). Mini Disc has been designed to be easier to handle, more durable, more portable, more superior digital recording technology. Consumers are starting to see Mini Disc as a great complement for CDs, and it’s not a replacement for CDs, but rather a replacement for conventional compact cassette tapes.


Mini Discs are magneto-optical discs that can store a wide range of data, including sound, images and text. Two distinct types of discs are conventional premastered disc, which is similar to CD for music-software publishing, and recordable disc, which can be recorded repeatedly more than one million times without loss of sound quality. Magneto-optical disc recording technology has been used for computer data storage system since the 1990s. Based on this technology, Sony developed direct overwriting technology with a similar recording density as CD in order to present the sound quality exactly like the CD's. A built-in shock-resistant memory control device is employed in almost every portable MD player. Also, digital audio compression system called by Sony ATRAC (Adaptive TRansform Acoustic Coding) is applied to enable manufacturers to use a 64-mm disc size.


Mini Disc is a hit in Japan and Europe with over six million units sold world-wide in 1997. American customers have also begun to realise the value of this highly portable, recordable digital audio format. The three main MD product lines are portables, stand-alones with home stereo systems, and composite units incorporated into car stereo systems. When MD players first came on this audio market in 1992, only portables and stand-alones were offered. In 1994 appeared the MD radio-cassette tape recorders, and one year later MD car audio system was finally developed. Among these three main lines, portables are currently the big sellers, but composite units have also been gaining market share since 1995.

It took three years for the MD player market to take off after the MD players were first released commercially by Sony in Japan in 1992. Ever since then, the other audio manufacturers like Panasonic, Aiwa, Denon, JVC, Yamaha and so on all started to step into this promising new market. Because of the strong competition and rapidly increasing sales, MD players in 1998 are much cheaper than before and with more features. Portable MD players cost from $250 to $700, some of which are featured with a 40 second shock-resistant memory, long lasting rechargeable batteries, LCD headphone remote and vertical jog dial. The stand-alone units and composite units are more expensive – starting from $450 to $2,600 (Denon DH 1100R Mini Disc Recorder). These units designed for home and car stereo systems usually come with CD and AM/FM stereo tuner and can recorded from a CD directly. Recordable blank discs are available in 60- and 74- minute lengths, and cost from $5 to $16.5. The main suppliers of blank discs are HHB, TDK and Sony.


MD providers define Mini Discs as the replacement of cassette tapes rather than CDs, and the main function of MD is to record audio performances from CDs or meetings with a high sound quality – near CD quality. By connecting the digital output of the CD player to the digital input of the MD recorder, consumers can easily get high digital recording quality sound. With MD, there is no need to cue a tape to fine blank space. You can use editing features such as combine, divide, erase, or move to flexibly edit your own MD album. It offers tremendous recording convenience with a rich digital sound. A 74-minutes disc can be used in monaural in order to get twice as much time (148 minutes). This is common when recording a meeting.


Sony invented the Mini-Disc system and has been the driving force behind its promotion. MD is intended to replace cassette tapes because the recording quality of conventional tapes is not good enough for consumers. Consumers also want to have something that is easy to edit but not so expensive as stereo equipment. When compared to recordable CDs, MDs are smaller, cheaper, re-writable and editable. Sony’s 'Where the Music Takes You' national as campaign led to great improving sales of the MD audio players because it made more consumers be aware of this new product.


The standard policy for portable MD players is the need to have a built-in shock-resistant memory. The portable players are meant to overtake the Walkman, which perform well even when the user is running or jumping. Without shock-resistant memory, both CD or MD portable players may be easily interrupted by shaking or swaying. In addition, the variety of choices, more advanced technology, easier-to-handle editing functions and gradually falling price are also factors that facilitate the growth of sales.


With a 6-year-old market, the sales and development of Mini Discs are definitely still on the rise. After MD has been widely accepted in Japan and Europe, America is the next main market that MD suppliers want to step into. Now with more and more American customers aware of this new technology and willing to try it, the sales of Mini Discs in 1998 are expected to double those of 1997.

But MD manufacturers still has some problems to solve if they want to expand the market. The primary challenges for MD providers to continue expanding the market will be to keep prices moving lower for both players and discs as well as to make the players easier to operate; many consumers still find the editing device too complicated for them. The MD players and blank disc cost still much higher than conventional cassette tape recorder/ player and blank tapes, therefore the manufacturers still have to offer price reductions in order to stimulate more sales. Portable MD players should be made smaller and be more energy-efficient (the longest-lasting rechargeable battery for MD portable can last 22 hours). Additionally, they should be all installed with a record function in every MD portable player, some portable players are without record function and it is hard for consumers to find premastered discs.

I think the most possible prospect for the future MD market would be 'Media on Demand.' It means that customers could order a MD at a record store and have it made (record from CD directly) while you wait. This 'Media on Demand' technology is new, similar to Video on Demand, but the problem of it would be the copyright issue. The MD market in the 1990s is still focusing on its 'recording' function, and now only in Japan are the premastered discs for audio purposes manufactured (many Japanese singers release MD albums). Possibly, in the future, when every household has one MD device as home stereo system, and then we can see all the CD albums in the MD form.


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