If you listen to music at normal volume, it won't spread to the 14th floor, and the sound will be uploaded from the bottom. You can hear the sound upstairs, especially in buildings with poor sound insulation or upstairs windows. It's obvious that all sound sources are in direct or indirect contact with the floor, and the floor can transmit the vibration of sound sources to the upstairs to drive the air downstairs to vibrate, so that people downstairs can hear the sound upstairs.

is spread through the medium. Because of the vibration of objects, sound can be produced. Sound is the fluctuation caused by the vibration of materials, and it can only be heard by media. When sound travels from downstairs to downstairs, the sound source needs to vibrate the air first, then the air drives the ceiling to vibrate, and then the floor upstairs drives the air to vibrate. In this process, the sound will spread through a layer of different media, and all of them will be seriously attenuated.