How does Apple set the best sound effects?

Take the mobile phone iPhone 13 as an example, the specific operation is as follows:

Mobile phone: iPhone 13

System: iOS 15.2

Software: Settings

1. In the opened setting interface, click the auxiliary function.

2. Click to enter the hearing aid device.

3. Turn on hearing aid compatibility.

4. Return to the accessibility interface and click Audio/Video.

5. Turn on the corresponding button switch on the right side of telephone noise reduction.

6. In the setting interface, click Music.

7. Open the corresponding button on the right side of the volume balance, and click to enter the equalizer.

8. After entering the equalizer, just choose your favorite music style.