The frequency range from 40Hz to 80Hz is called low frequency. This frequency band includes: bass drum, double bass, cello, bassoon, bassoon, bass trombone, bass clarinet, tuba horn, French horn, etc.

The intermediate frequency spans frequencies between three octaves (320Hz, 640Hz, 1280Hz) from 160Hz to 1280Hz. This frequency band contains almost all musical instruments and vocals, so it is the most important frequency band.

The high frequency range is from 2560Hz to 5120Hz, because except for the upper range of the violin, the high range of the piano, and the piccolo, most other instruments will not appear in this frequency band.

Extended information:

Common audio formats——

1. CDA format. In the "Open File Type" of most playback software, you can see the *.cda format, which is the CD audio track. In fact, for each song on the record, when the CD record format standard was determined, it was earlier than the CD-ROM format used in computers, so of course the CD-ROM drive was not considered when the standard was originally set. CD records can also be recognized.

2. WAV waveform audio format. WAV is a PC standard sound format jointly developed by Microsoft and IBM. The file suffix is ??.wav. It is a universal audio data file. The WAV format is usually used to save some uncompressed audio, that is, audio that has been encoded by PCM, so it is also called a waveform file. It is stored according to the waveform of the sound, so it takes up a large storage space.

3. MP3/MP3 Pro format. MP3 is an audio compression technology, its full name is Moving Picture Experts Group Audio Layer III (Moving Picture Experts Group Audio Layer III), referred to as MP3.

Baidu Encyclopedia-Audio Signal