Noise-canceling headphones from Sennheiser are always equipped with active noise-canceling technology. There are also noise-isolating or noise-reducing headphones on the market, which only provide passive noise reduction. Noise-isolating and noise-reducing headphones do not contain the same technology and only protect from ambient noise through the construction of the headphones.
Over-Ear Headphones, for example, completely cover the ears and help to block out ambient sound. Earbuds sit directly in the ear canal, so that users perceive less ambient noise. However, noise-isolating headphones always carry the risk of hearing damage – for example, if listeners turn up their music too loud to mask background noise.