According to the researchers, this innovative device has the ability to counteract noise as effectively as a four-meter-thick wall, but with a thickness of just 17 millimeters. The operation of these plasma speakers is based on the generation of sound through a set of parallel cables that create an electric field powerful enough to ionize the air particles that are around. Also, the charged ions are accelerated through the magnetic field lines, displacing the remaining non-ionized air and producing the sound. But, what makes this system even more impressive is its ability to absorb sound, much like the mechanism of headphones equipped with Active Noise Cancellation (ANC) technology.
EPFL experts have harnessed plasma speaker technology to develop an Active Noise Cancellation (ANC) system that is thinner, lighter and more affordable compared to your drivers’ conventional options. This state-of-the-art system dispenses with a membrane and has the ability to extend its operating frequency range, as well as interact more effectively with high-frequency or fast-changing sounds. Stanislav Sergeev, a researcher in EPFL’s Acoustics Group and lead author of a paper published in the journal Nature detailing this breakthrough, explains: “Our goal was to minimize the impact of the membrane, which has significant weight. But what could be lighter than air? Air itself.”
EPFL researchers have taken advantage of plasma loudspeakers to develop an ANC system that is thinner, lighter and cheaper than its traditional counterparts. This new system does not require a membrane and has the ability to expand the range of frequencies in which it can work, as well as interact more effectively with sounds that change quickly or have high frequencies. Stanislav Sergeev, a researcher in EPFL’s Acoustics Group and lead author of the Nature paper describing this discovery, explains: “We wanted to minimize the effect of the membrane, which has considerable weight. But what can be as light as air? The air itself.
Researchers have made a breakthrough discovery by discovering that plasma speakers are highly sensitive and efficient in canceling high and low frequencies, something that has not been achieved in previous experiments. This represents a significant advance in noise cancellation technology, as low frequencies, such as sounds near 20 Hz, are especially difficult to neutralize. Normally, a 17mm thick layer of material is required to absorb noise at these very low frequencies, but with these new plasma speakers, a similar effect is achieved without the need for a membrane and with a much thinner device.
This advance not only offers a more efficient noise cancellation system, but is also lighter and cheaper to manufacture. Plasma loudspeakers could have applications in a variety of fields, from building and office construction to the design of headphones and more advanced electronic devices. Although this technology is still in the research and development stage, the potential for plasma speakers to revolutionize the way we cancel and control noise is undeniable. EPFL scientists are working to improve and optimize this system, which could lead to even more significant advances in noise cancellation in the near future.