The principle of musical doorbell means that the music emitted by the musical doorbell is realized through mechanical movement. Most musical doorbells produce music by using a motor to drive a small tambourine or chime. As the motor spins, the tambourine or chime also spins and makes music when it hits the wire or piece of metal. Musical doorbells can also produce music in other ways, such as using electronic components or chips to simulate the sounds of musical instruments.

The mechanical part of the musical doorbell includes several main parts: motor, drive shaft, tambourine/chime and steel wire/metal sheet. The electric motor is responsible for driving the entire system and driving the tambourine/bell to rotate through the drive shaft. The tambourine/chime makes a sound when it hits the steel wire/sheet of metal during rotation.

Music doorbells can also be implemented electronically. In electronic music doorbells, chips or circuits are usually used to store music data and control audio output. When the trigger is activated, the chip or circuit reads the music data and plays the music through the speaker.

The music doorbell can select different music according to needs and customize the music list. Some high-end music doorbells can connect to the Internet, allowing users to store and manage music in the cloud.