1. CD format

In the "Open File Type" of most playback software, you can see the *.cda format, which is the CD audio track. The standard CD format is a sampling frequency of 44.1K, a rate of 88K/second, and 16 quantization bits. Because the CD track can be said to be approximately lossless, its sound is basically faithful to the original sound.

CD discs can be played on CD players or replayed using various playback software on computers. A CD audio file is a *.cda file. This is just index information and does not actually contain sound information. Therefore, regardless of the length of the CD music, the "*.cda file" seen on the computer is 44 bytes long. .

2. WAV

A sound file format developed by Microsoft. It conforms to the PIFFResource Interchange File Format file specification and is used to save audio information resources on the WINDOWS platform. It is used by the WINDOWS platform and supported by its application.

The "*.WAV" format supports multiple compression algorithms such as MSADPCM and CCITT A LAW, and supports a variety of audio bits, sampling frequencies and channels. The standard format of WAV files is the same as the CD format, which is also 44.1 K's sampling frequency, rate is 88K/second, and 16 quantization bits. As you can see, the sound file quality of WAV format is almost the same as that of CD. It is also a widely popular sound file format on PCs.

3. MP3

The MP3 format was born in Germany in the 1980s. The so-called MP3 refers to the audio part of the MPEG standard, which is the MPEG audio layer.

It is divided into 3 layers according to the difference in compression quality and encoding processing, corresponding to the three types of sound files: "*.mp1"/"*.mp2"/"*.mp3".

What needs to be reminded is that the compression of MPEG audio files is a kind of lossy compression. MPEG3 audio coding has a high compression rate of 10:1~12:1, while basically keeping the low audio part intact. Distortion, but sacrifices the quality of the 12KHz to 16KHz high audio part of the sound file in exchange for file size.

Music files of the same length, stored in *.mp3 format, are generally only 1/10 of *.wav files, and the sound quality is inferior to sound files in CD format or WAV format.

Due to its small file size and good sound quality; when it came out, there was no other audio format that could compete with it, thus providing good conditions for the development of the *.mp3 format. To this day, this format is still all the rage.

4. WMA

High-fidelity sound pass-band bandwidth, better sound quality, strong background, sound quality is better than MP3 format, and far better than RA format. It is developed with Japanese YAMAHA company The same as the VQF format.

It achieves a higher compression rate than MP3 by reducing data traffic but maintaining sound quality. The compression rate of WMA can generally reach about 1:18.

Another advantage of WMA is that content providers can add anti-copy protection through DRM (Digital Rights Management) solutions such as Windows Media Rights Manager 7. This built-in copyright protection technology can limit the playback time, playback times and even playback machines, etc.

5. VQF

Its core is to achieve a higher compression ratio by reducing data traffic but maintaining sound quality. It can be said that it is also very advanced technically, but due to poor publicity , this format is difficult to use.

*.vqf can be played with Yamaha player. At the same time, Yamaha also provides software for converting *.wav files to *.vqf files. The document's lack of character, combined with its lack of publicity, is almost a death sentence.