How do noise cancelling headphones work? Royce Wilson, news.com.au, writes about noise cancelling headphones, the cure-all to our modern noisy world. But have you ever wondered how they actually work? Wilson reports that there are “two types of noise cancelling technologies for headphones — passive and active,” and he asked University of Queensland School of Information Technology and Electrical Engineering research fellow and lecturer Dr Konstanty Bialkowski about the different approaches. Dr. Bialkowski said that the passive technology is “like having a cup around your ear that reduces high-frequency noise” (“people talking or high-pitched squealing”), while active cancellation is for low-frequency noise (e.g., low-pitched hum like a car engine, aeroplane engine or a fan). With active cancellation, the headset, which has a microphone, “knows the distance between the microphone and your ear and it makes [a] complete opposite noise” to cancel out the distracting noise.
Click the link for the full article, which includes a review of the Sony’s MDR-1000X wireless noise cancelling headphones.