A sound-suppressing silk fabric

Researchers at MIT in the US developed a thin silk fabric that can be used to create quiet spaces.

There are many acoustic materials on the market, creating less noisy and therefore more pleasant surroundings. Generally, with these materials, whether they are made of biobased resources or synthetic ones, it’s the thicker the better.

The new fabric by MIT is barely thicker than a human hair. It works thanks to a special fibre, which vibrates when a voltage is applied to it. The researchers leveraged those vibrations to suppress sound in two different ways. The first way is to generate soundwaves that interfere with an unwanted noise to cancel it out, similar to noise-cancelling headphones. This works well in a small space, like your ears, but does not really work in large enclosures.

In the other, more surprising technique, the fabric is held still to suppress vibrations that are key to the transmission of sound. This prevents noise from being transmitted through the fabric and quiets the volume beyond. This second approach allows for noise reduction in much larger spaces, like rooms or cars.

The noise suppressing fabric can be made of common materials like silk, canvas, and muslin. It could be used, for instance, to make dividers in open work spaces. When they tested the silk fabric in direct suppression mode, the researchers found that it could significantly reduce the volume of sounds up to 65 decibels (about as loud as enthusiastic human conversation). In vibration-mediated suppression mode, the fabric could reduce sound transmission up to 75 percent.

Image: MIT / iStock