We all know how to block the DC offset of an AC signal — that just requires putting a capacitor in series, right? But what if the AC signal doesn’t alternate very often? In that case, things get a ...

The most obvious way to get rid of ambient noise is to employ some form of passive or active noise cancellation (ANC). The type of ANC we’re familiar with today was coined in 1989 by Dr. Amar Bose ...

Soft whirring sound of low-frequency vibrations cannot be easily detected because it is not loud. But once detected, it can be hard to ignore. Often, residents complain of the annoyance caused by ...

Pusan National University researchers developed a novel meta-silencer that reduced broadband low-frequency noise by leveraging the acoustic black hole and rainbow trapping effects, resulting in ...