Appearance
The MD disc is indeed very small, the size we usually see is 7cm x 6.75cm x 0.5cm, but this time it is the outer protective shell, the real MD inside The diameter of the disc is only 6.4cm, the conventional MD can only store 140MB (data mode) or 160MB (audio mode), while the CD can store 650MB (CD-ROM) or 740MB (CD-AUDIO).
Classification
MD discs can actually be divided into three types: the purpose of pre-recorded MD discs
(Premastered MD), recordable MD (Recordable MD), Hybrid MD (Hybrid MD). Among them, recordable MD and hybrid MD can be repeatedly erased, which is also the biggest difference between MD and CD. The MD machine itself can be divided into a recordable/downloadable MD machine (with a write head and a read laser head) and a single-play MD machine (only the laser head used to read data, not writing). Due to the use of specially developed magnetic heads, laser heads, mechanical parts, etc., it can be said that the MD machine is a product with high technical content that integrates optical, magnetic, mechanical, and electrical technologies. It is compatible with general portable CD players and tapes. Compared with the CD player, the MD player not only has the sound quality close to the CD (the background noise is lower than that of the CD, the actual sound quality is slightly lower than the CD sound quality, but it is sufficient to meet the requirements of music lovers), the more reliable data storage period, and the performance of a tape drive Repeated erasing function. For the average consumer, you can simply think that the MD player is the neutralizer of the CD player and the tape player. The MD machine allows users to record music by themselves (it needs to be realized by the SonicStage software that comes with the machine), and can record all sounds from all audio source devices through suitable connection methods (analog audio cable, optical fiber cable, microphone). At the same time, the user can edit the name, divide, move, and delete the music recorded on the MD disc. Because MD and CD use digital method to record music information, so it can also perform fast track change, fast forward, program sequence play, random play and repeat play like CD. Moreover, the advantage of digitally recording music is that it can avoid background noise during tape playback, and provide users with a purer music enjoyment.