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MP3 or Size does Matter…

If you have ever heard about MP3 file and wondered what it is or how it works then it will be my pleasure to introduce you „what is an MP3“. Making of MP3 file is based on compressing original music file into the file of smaller size but almost the same quality. Principle of this compression is based on imperfection of human ears, which can’t catch the whole scale of sounds. These are sound which are above or below the scale of tones which can be heared by human (above 20 000 Herz and below 20 Herz). The MP3 format is a compression system for music. The MP3 format helps reduce the number of bytes in a song without hurting the quality of the song's sound. The goal of the MP3 format is to compress a CD-quality song without noticably affecting the CD-quality sound. With MP3, a 32-megabyte song on a CD compresses down to about 3 MB. This lets you download a song in minutes rather than hours, and store hundreds of songs on your computer's hard disk without taking up that much space. However, the quality of this compression wasn’t always as good as now. Before MP3s we knew MP1 and MP2 files, although these weren’t used almost at all.
To make a good compression a technique called perceptual noise shaping is used. It is "perceptual" partly because the MP3 format uses characteristics of the human ear to design the compression algorithm. For example:
• There are certain sounds that the human ear cannot hear. • There are certain sounds that the human ear hears much better than others. • If there are two sounds playing simultaneously, we hear the louder one but cannot hear the softer one. Using facts like these, certain parts of a song can be eliminated without significantly hurting the quality of the song for the listener. Compressing the rest of the song with well-known compression techniques shrinks the song considerably. When you are done creating an MP3 file, what you have is a "near CD quality" song. The MP3 version of the song does not sound exactly the same as the original CD song because some of it has been removed, but it's very close. MP3 today (quality):
MP3 is so popular because of its small size, but mainly because of a high quality which can be found in few megabytes.

For example: A size of 4 minute song is normally about 40 megabytes but after compressing it into MP3 file it has only 4 megabytes and the quality is almost about the same.
For playing MP3 files on computer we use MP3 players. The most popular are Winamp or Sonique. In the last two years portable MP3 players has been introduced. We can devide them into two groups:
The first one looks like standard discman with the slight difference, that it can read MP3 files from a CD, and because these are smaller size, we can keep about 200 songs on one CD. The second mentioned group are players into which we can record songs straight from computer. The numer of songs that we can record to this player depends on size of its disc, but it ranges from 16 songs to 5 000 songs. ---------------------------------------------------------------------------------------------------------------
If you want to have MP3 file you can use one of these two ways:
a) you can compress it on your own computer straight from CD using programmes called grabbers
b) or you can download it from internet ( but this one is not legal !!! ). a) If you have a CD collection and would like to convert songs from your CDs into MP3 files, you can use ripper and encoder software to do just that. A ripper copies the song's file from the CD onto your hard disk. The encoder compresses the song into the MP3 format. By encoding songs, you can play them on your computer or take them with you on your MP3 player.
If you would like to download and then listen to MP3 files on your computer, then you need:
• A computer
• A sound card and speakers for the computer (If your computer has speakers, it has a sound card.)
• An Internet connection .
• An MP3 player (a software application you can download from the Web in 10 minutes)
Knowing about the MP3 format isn't half as interesting as using it. The MP3 movement -- consisting of the MP3 format and the Web's ability to advertise and distribute MP3 files -- has done several things for music:
• It has made it easy for anyone to distribute music at nearly no cost (or for free). • It has made it easy for anyone to find music and access it instantly. • It has taught people a great deal about manipulating sound on a computer. The MP3 movement is one of the most amazing phenomena that the music industry has ever seen. Unlike other movements -- for example, the introduction of the cassette tape or the CD -- the MP3 movement started not with the industry itself but with a huge audience of music lovers on the Internet. The MP3 format for digital music has had, and will continue to have, a huge impact on how people collect, listen to and distribute music.

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