What if I were to tell you that in the future magnetic cone speakers would be replaced by a paper thin cone with no electromagnets or any moving parts for that matter? Sounds like science fiction doesn't it? Well this could become a reality with some old but revisited theories regarding thermoacoustic energy transmission.
A study of heating and cooling very thin platinum foil to transmit sound was introduced by Harold DeForest Arnold (Western Electric Company, Inc.) and I. B. Crandall (AT&T) in 1917 in an article, The Thermophone as a Precision Source of Sound, in the Physics Review: Volume 10. I was reading an article on the BBC Technology page entitled Nanotubes: Can we make speakers as thin as paper? This article talking about a team from China that revitalized this study back in 2008 and has found that they can create thermoacoustic sound from a thin, clear film made from carbon nanotubes (CNT).
Don't get too excited yet though because while the material is perfectly suited for applications such as sonar it isn't clear whether it has a good enough frequency response to compete with a hi-fidelity home sound system. They have also run into issues regarding the level of output with CNT films. They found that they can improve the output performance by adding a flexible membrane filled with inert gas around the CNT films which transfers acoustic vibrations from the CNT into the gas and then into the surrounding air. They can also increase the level by compiling layers of the materials together.
If you're unfamiliar with carbon nanotubes you can watch this short Nova video that will explain some of its extraordinary characteristics.
I don't know about all of you but I would love to see/hear a prototype.
Jared,
ReplyDeleteThat is very interesting; I would love to see and hear what they have come up with as well. The video you linked was hilarious. I always love it when the scientists are extremely in love with their work and they also have the best jokes. It is amazing the properties of the carbon nanotube, I would spend all day spinning them to make something out the thread.
Kyle Schroeder
Tubes and Transistors
I love watching science shows for that exact reason! This kind of reminds me of these glass speakers I came across on Instructables (http://www.instructables.com/id/Glass-Speakers/). Where's a sound museum where I can go hear these things? haha.
DeleteSounds really interesting. Speakers would definitely get lighter, and the quality to cost ratio would definitely increase, but I have a feeling there will still be people who want the old "vintage" sound of true cone speakers. It will possibly be the new vinyl vs. digital debate.
ReplyDeleteAbsolutely; I have a feeling that I will be one of the hesitant ones.
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