Carbon nanotube headphones may be reasonably priced
A group of researchers have created a very unique set of headphones that don't use moving parts for the speaker drivers. Rather than using moving parts, the speakers in these headphones use carbon nanotubes. Carbon nano tubes have been researched for a number of uses, including making smaller transistors for computer chips.
The headphones use what's called the thermoacoustic effect to create sound. The thermoacoustic effect uses the expansion and contraction of air to create sound. "We found that processing the carbon nanotube film into thin yarn arrays doesn’t weaken the thermoacoustic effect but can greatly improve the device robustness and durability. And the new designmounts the nanotube structures on silicon chips that are compatible with existing manufacturing methods. The thermoacoustic chips could be easily integrated into circuit boards for speakers with other electronic elements, such as control circuits," said Yang Wei, one of the project creators.
So far, there's no indication of when headphone such as these might be available on the market. However, there is some indication that nanotube speakers may be reasonably priced when they do come to market.