It should be lossless sound quality. The high sound quality is also processed from lossless sound quality.

But if your headphones or player are not professional enough, you may not be able to hear it. Unprofessional people like us can't hear the difference...

[The following is taken from Baidu Encyclopedia]

As a current hot topic, many people are not very clear about lossless audio formats. format. In fact, the main difference lies in understanding the music file format played in MP3. Currently, the music file playback formats are divided into two types: lossy compression and lossless compression. Music files using different formats have huge differences in sound quality performance.

The MP3, WMA, and OGG we commonly see are called lossy compression. As the name suggests, lossy compression reduces the audio sampling frequency and bit rate, and the output audio file will be smaller than the original file. Another type of audio compression is called lossless compression, which can compress the volume of the audio file into a smaller size while preserving 100% of all the data of the original file. After restoring the compressed audio file, it can be compared with the original file. Same size, same bitrate. The current lossless compression formats include APE, FLAC, WavPack, LPAC, WMALossless, AppleLossless, TTA, Tak, La, OptimFROG, and Shorten. The common and mainstream lossless compression formats currently include APE, FLAC, TTA, and TAK.

There is no clear definition of "high quality" or "high-quality audio".