Feasibility of a high-powered carbon nanotube thin-film loudspeaker.

The thermophone, conceived in 1917 by Arnold and Crandall, was a unique thermoacoustic loudspeaker. The high heat capacity per unit area (HCPUA) of thin-film materials at that time limited the usefulness of thermophones. Recently, researchers of carbon nanotubes (CNTs) have developed techniques to create a super-aligned thin-film of multi-walled CNTs, possessing extremely low HCPUA.