Researchers at the EPFL Acoustic Group have made significant advancements in the field of noise cancellation. While active noise cancelling (ANC) technology has proven effective in headphones and cars, implementing it at room scale presents challenges due to the escape of low-frequency sounds. However, a revolutionary plasma-based noise-cancelling technology has the potential to overcome this limitation.
Ancient Technology Meets Modern Innovation
ANC technology relies on measuring sound wave pressure in speakers and countering it in reverse to cancel out the waves and block noise. Current room-scale ANC setups require large arrays of speakers to be installed on walls, resulting in a complex and cumbersome solution. In contrast, the EPFL researchers have pioneered a lightweight approach to address this problem.
The EPFL team has experimented with super-slim sheets of plasma-based ionic speakers as a means to reduce and eliminate noise. These speakers are remarkably lightweight, easy to manufacture, and cost-effective. They function similarly to ionic propulsion systems, which ionize ambient air using an electric field through the plasma.
This process generates both positively and negatively charged particles that are accelerated and exerted against the surrounding air, creating pressure waves. By adjusting the voltage applied to these ionic speakers, the airflow can be modulated accordingly. While these compact speakers may not satisfy audiophiles, they offer a significant reduction in weight compared to traditional speaker membranes used in similar systems.
The Power of Plasma-Based Noise Cancellation
Plasma-based noise cancelling technology offers advantages in canceling both high and low-frequency wavelengths. The EPFL researchers discovered that it performed admirably even in attenuating low-frequency sounds. The effectiveness of this new tech is noteworthy.
A report from New Atlas reveals that using a mere 17 mm (0.6 inch) piece of material, these innovative speakers successfully cancelled out lower frequency wavelengths. In contrast, current mainstream noise reduction foams or sound-absorbing walls require a staggering 4 m (13 foot) thickness to achieve similar results. This breakthrough technology has the potential to create noise-cancelling environments in various settings, including rooms, planes, and automobiles.
A Promising Future
Although immediate implementation is not guaranteed, the field of audio technology is poised for significant advancements with the introduction of plasma noise-cancelling technology and MIT’s paper-thin speakers. These innovations open up exciting possibilities for creating quieter and more peaceful environments in our daily lives.