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MP3 players Related Content

MP3 is the international standard MPEG audio compression in the third layer pattern, the sound signal compression format, the Chinese also known as "Computer Network Music." The third layer of MPEG audio compression than the first layer and second layer coding to be complex, but the sound quality than the first and second floors, even in comparison with CD sound quality. CD, sample rate frequency 44.1MHz, 16Bits, the amount of data to 1.4Mbps, while the corresponding amount of MP3 data, only 32kbps ~ 320kbps, is the raw data in 1 / 4 to 1 / 40. That is the traditional one CD can now be stored 4 to 40 times the music, but in the human ear sounds, feel the sound effects are no different.
Mp3 is a kind of compression and decompression of the calculation method used to deal with a high percentage of sound information. Sports MP3 Players generated sound files sound close to CD, the file size is only one-twelfth of CD. If a disc can store about 15-20 first of the CD format music, if saved as MP3 format, can store several hundred songs, which is its charm. MP3 occurs first goal is to reduce the file size to facilitate data transmission in the network, and to maintain the quality of the original close of play. MP3 players can reach the compression rate of 1 / 4 to 1 / 40, but the sounds in the human ear, but no distortion, because it will exceed the human hearing range of the sound removed from the digital audio without altering the most The main voice. In addition, MP3 mini dv player can upload, download any other form of computer files, iPod MP3 Players with removable storage capabilities. MP3 player is actually a function of specific small computer. Small body in the MP3 player, the MP3 player has a memory (memory card), MP3 player displays (LCD display), disney mp3 player central processing unit [MCU (microcontroller) or MP3 player decoder DSP (digital signal processor), etc..
MP3 player is the use of digital signal processor DSP (Digital Sign Processer) to complete the processing and transmission, and decoding MP3 files of the task. DSP in charge of player data transmission, device interface control, file playback decoding activities. DSP can be in a very short time to complete a variety of processing tasks, and this process consumes very little power (this is it suitable for portable players, a distinctive feature).
First MP3 song files from the memory and read out the memory on the chip, the signal → to decode the signal to decode → solution out through the DAC will convert digital signals into analog signals → then converted analog audio amplification → low-pass filtered to the headphone output, the output is what we heard after the music.
Into the 21st century, MP3's rapid development so that people no longer content to MB flash memory capacity of the unit. January 2000, the audio hardware in the field of Big Brother introduced the world's first innovative 2.5-inch hard drive MP3 - NOMAD Jukebox, Hello Kitty MP3 Players using Fujitsu 6.4GB 2.5-inch hard drive as storage media that can store the equivalent of more than 100 Zhang CD, MP3 music, far beyond the capacity of flash memory was MP3, but volume is very alarming, than we have CD players in general bigger, its shape is also very similar with the CD player. Although the use of hard disk media, but in order to ensure smooth movement to music can be played, can support innovation and to design a 5-minute earthquake 8MB cache, even in conditions of moving out and will not appear Music Jumping phenomenon.
Meanwhile, NOMAD Jukebox, or the first with direct MP3 record features one. The emergence of direct recording functions, make MP3 break the limitations of relying on computer access to resources. Of course, this TreadTang CD anywhere, anytime can be converted to MP3 for free, has also drawn the RIAA's "concern", but fortunately innovation comes from Singapore, RIAA can only be beyond the reach of, and now, direct MP3 record-type has long been popular.