Noise cancellers are devices that use advanced signal processing techniques to reduce or eliminate unwanted noise from audio signals. They are commonly used in audio systems, headphones, and other applications where noise can interfere with the quality of sound. Noise cancellers work by analyzing the incoming signal and generating an inverse signal that cancels out the unwanted noise. They can be designed to work with different types of noise, including white noise, pink noise, and ambient noise. High-quality noise cancellers are essential for achieving clear and accurate sound reproduction in noisy environments, as well as for improving the overall listening experience.