Key is Inverse audio.
The basic concept of how active noise cancellation works is simple. Think of a sine wave on a graph, with the height of its arc in positive territory. Now, imagine the exact inverse of that, with its lowest point lining up with the peak of the positive sine wave. Just like adding 1 to -1 results in 0, these two waves cancel each other out. So if the waves represent audio signals, they essentially nullify each other, creating silence.

That’s what ANC is. Microphones built into our ANC headphones capture surrounding noises and audio processing circuitry then takes those noises and generates their inverse to cancel them out in real time.