Development  Trends of HIFI Digital Audio 

When HIFI Bluetooth audio is concerned, you have to talk about digital audio, and have to talk about HIFI. After passing media changed of records, tapes and CD, we come to the digital age from the analog era. Regardless of how to HIFI analog technology defend tradition, and also regardless of how CD-ROM to defend its territory, they cannot stop the tide of digitization billowing forward. Nevertheless, also HIFI digital creeping forward in the lost, let HIFI fans not know what course to take from assortments of audio equipment, from valuable vinyl equipment to the high price of professional players, from the CD player to DVD, from the PC to your tablet computer, from MP3 to smart phones, from online play to the cloud from the network equipment ...... really dazzling, they are in competition to the last, it seems that computers and smart devices like CD players to get the final approval, which the computer (including the PC and moveable Tablet) to become the highest penetration rate of audio equipment, and the CD drive is the most trusted equipment by HIFI fans. It is the first choice that CD grade and above format of music has become.

CD music is based on the basic principles of the design of the Nyquist sampling theory, human ear can hear sound from 20Hz-20KHz; so it is able to reproduce 20KHz frequency signal if sample rate to take 16bit/44.1KHz, but in recent years Popular 24bit/96-192KHz sampling rate music is super ultimate choice by HIFI audiophile (such a high form of music is difficult to play in CD player). If distortion of CD drive playback music is <0.01%, SNR and dynamic range are is > 100dB, it are high-fidelity music, compared to their original analog tape or vinyl album, noise ratio is improved at least 100 times.

Computer seems to win because of its collection of music files free music storage and management of intelligence, it relies on Internet music resources and then exists. On Internet, now widely popular music format is divided into three broad categories:

(A) Uncompressed Music – CD. Original uncompressed PCM digital music of CD, including WAV/16bit-24bit/44.1KHz-192KHz, which is ripping track of original CD uncompressed file format, a file is 60 minutes 650M , and is a shared format without any copyright issues.

(2) Lossless compression music - APE, FLAC ......, etc., according to rate 1/2 CD compressed files for easy storage and network transmission, compression and decompression without sacrificing the original music details, so 80% network music is this format file, APE is copyright format, FLAC and  others are shared formats.

(3) Lossy compressed music - MP3, WMA and so on. Although MP3 files is smaller, it is based on the loss of detail of the compression music, so that a reproduction sound field cannot achieve full CD quality, cannot meet demand listening of HIFI audiophiles, both have format copyright.

These formats of music is available for free download online popular, but the core of the card-reading system cannot play SD card and U disk or mobile hard disk HD music, only play lossy compression MP3 music format. HD lossless music also relies on a computer or CD drive to achieve replay.

This is why CD player has remnants of a little bit of space still up to now, convenience of computer has been questioned as the source, "CD-ROM is dead" is a foregone conclusion, those major record companies are seeking new distribution methods, where HIFI will go? How to drive high-definition music from your computer and freed, which is the historical mission of HIFI music. WISTAO boldly predicted that a new type of alternative music CD distribution media might be "flash" that is, U disk or SD card, as it is equipped with suitable playback devices, it has all the properties of computer music and CD music both, if add additional features of fast, low cost, and other peripheral attributes, which is sought by HIFI audiophiles is inevitable. This will be a big product system, designed to fully comply with fidelity, fast and low-cost intelligent playback product attributes, set solid tone or a HIFI Bluetooth module receives lossless audio formats, integrated power amplifier IC or discrete components of hi-fi amplifier (or HIFI coaxial speakers) into a system, and equipped with passive speakers, these can be composed of a high-fidelity playback system with designed self-contained, high integration, in one step.

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