MP3
MP3 is a high-compression coding and decoding system that is now used for transmitting audio signals over Internet links and for storing audio signals in compact computer file form. MP3 allows the construction of small players that store, typically, 40 min of music, but contain no moving parts. Because MP3 is a lossy form of compression, the MP3 deck for hi-fi systems has not emerged so far, but we should remember that the compact cassette was also considered unfit for hi-fi uses in its initial days. The Minidisk uses similar compression methods.
The name MP3 began as an extension to a filename, devised to distinguish sound files created using MPEG-1 Layer III encoding and decoding software. The PC type of computer makes use of these extension letters, up to three of them, placed following a dot and used to distinguish file types. For example, thoughts.txt would be a file called thoughts, consisting purely of text, and thoughts.doc would be a document called thoughts, which could contain illustrations and formatted text, even sounds. A file called thoughts.jpg would be a compressed image file, and thoughts.bmp would be an uncompressed image file. There are many such extensions, each used to identify a specific type of file.
The same MP3 extension is used for sound files that have used MPEG-2 Layer III with a reduced sampling rate, but there is no connection between MP3 and MPEG-3. MP3 files use a compression ratio of around 12:1, so that MP3 files stored on a recordable CD will provide about 12 h of sound. See later for a description of DAM-CD.
The main use of MP3, however, has been the portable MP3 player, which allows MP3 files to be recorded from downloads over the Internet. This has made MP3 very much of an audio system for the computer buff, but like all matters pertaining to computing, this use is likely to spread. MP3 is unlikely to appeal to those who seek perfection in orchestral music (let’s face it, what system does?) but for many other applications it offers a sound quality that is at least as good as anything that can be transmitted by FM radio or obtained from a high-quality cassette.
● The advantages are many. You can load the memory up with music that you like, deleting anything you don’t want to hear again. You can play tracks in any order, select tracks at random, and store other music on your PC until you want it on your MP3 player.
One other attraction is rather an illusion, that music is free. Many Internet sites offer MP3 files at no direct cost, but you have to pay for the large amount of telephone time you need for downloading them. Unless you want only fairly small-scale works you will need a fast Internet connection, such as you get with cable TV firms. The alternative is to spend a lot of your income paying for BT phone calls, although alternatives are appearing almost daily. If you really want to download a lot of music it makes sense to take out a fast line or use one of the offers of a fixed charge for unlimited Internet use. Either way, your music is not exactly free.
In addition, “free” music is often made by unknown artists in strange places. Sometimes you will find an excellent recording made by a Russian orchestra that is unable to raise the money to make CDs or to go on tour. Other recordings may have quite awful quality, and there is always the suspicion about some of the worst recordings that some tracks may even be acquired illegally, using miniature recorders taken to live concerts. Some may even be copied from existing CDs. However, the MP3 system is an excellent way for any person or group to make and record their own music and distribute it worldwide without the costs involved in making a CD.
● There is nothing illegal about possessing MP3 files, no matter how they were obtained originally, on your computer. If you make copies and distribute them, that’s another matter, and the usual laws of copyright apply. It is certainly illegal to convert CD tracks and distribute the music in MP3 format without the permission of the copyright holder.