Scientist Develop Novel ‘Acoustic Material’ That Cancels Sound


Scientists developed an Open Ring-like structure that works mathematically for chopping out sounds whereas sustaining airflow. It restricts the sound flow direction and cancels noise

According to the latest research reports developed by scientists created mathematically for chopping out sounds while maintaining airflow, scientists say in a statement.

Although noise-mitigating barricades, called sound baffles, can help drown out the whoosh of rush hour traffic or contain the symphony of music within concert hall walls, the long approach not suited well to these situations where airflow is also critical, said, researchers.

The Scientists sealed the loudspeaker into one end of a PVC pipe. On the other end, the tailor-made acoustic metamaterial was fastened into the opening. With the hit of the play button, the experimental loudspeaker set-up came oh-so-quietly to life in the lab. Standing in the room, based on your sense of hearing alone, you’d never know that the loudspeaker was blasting an irritatingly high-pitched note. If, however, you peered into the PVC pipe, you would see the loudspeaker’s subwoofers thrumming away.

The researchers calculated the dimensions and structure and functions that the metamaterial would need to have to interfere with the transmitted sound waves, preventing sound — but not air — from being radiated through the open shape.

Based on their various calculations, they modeled the physical dimensions that would most effectively use noise cancellation in a significant way. Bringing those models to life, they used 3D printing to materialize an open, noise-canceling structure made of plastic.

The lab suddenly echoed with the screeching of the loudspeaker’s tune. By comparing different sound levels on different variations, the team found that they could feel silence nearly all – 94% to be exact — of the noise, making the sounds emanating from the loudspeaker invisible to the human ear.