Scientists from the University of Exeter developed a speaker that does not need mechanical vibration. At the heart of his work is graphene, which when heated and cooled creates sound waves. About their development, researchers reported in the journal Scientific Reports.

A new graphene speaker is a chip the size of a thumbnail.

Inside the device is a speaker, amplifier and equalizer.

The speaker works by means of thermoacoustics, which converts heat into sound. According to researchers, the device can create a "rich sound palette," carefully monitoring how and where electricity flows through graphene. The heating and cooling cycles also allow the speaker to mix, amplify and equalize several audio frequencies simultaneously, which can increase its output power, creating sounds in the ultrasonic range.