Music library size: MP3 players can store a large number of music files, far exceeding the number of songs that traditional car stereos can hold. This is a significant advantage for users with large music collections. Sound quality: Some high-end MP3 players provide excellent sound quality. For listeners with higher audio quality requirements, using MP3 players can enjoy clearer and richer sound effects through the car audio system. Convenience: The portability and ease of use of MP3 players allow users to easily switch between different devices, for example, using a computer to download music at home and then playing it through an MP3 player in the car. Diversity of functions: Modern MP3 players are not limited to playing music, but may also include functions such as video playback and audio books, providing users with more entertainment options. To sum up, although the built-in speakers of ordinary cars can already meet the basic needs of music playback,