{"podcast":{"title":"Smile with Daniel","slug":"smile-with-daniel-7904799","podcast_index_feed_id":7904799,"rss_url":"https://media.rss.com/smile-with-daniel/feed.xml","website_url":"https://www.instagram.com/smilewithdaniel/","image_url":"https://media.rss.com/smile-with-daniel/podcast_cover_20260609_080604_29f16c286804786aa21b84148324d60c.jpg","author":"Smile with Daniel","episode_count":53,"summary":"Every night, Daniel asks his mom a question. Why do we call money \"bucks\"? Why do we get dizzy when we spin? Why do we knock on wood? The answers are always surprising, and a lot more interesting than you'd expect. Smile with Daniel is a short podcast for curious kids and the adults who love them. Real questions. Real answers. No dumbing it down. New episodes every week. Find us @smilewithDaniel everywhere.","last_synced_at":"2026-08-02T04:19:07.455261+00:00","page_url":"https://stenobird.com/podcast/smile-with-daniel-7904799"},"episode":{"title":"The Science Behind Noise Cancelling Headphone","slug":"the-science-behind-noise-cancelling-headphone","published_at":"2026-07-21T19:33:03+00:00","page_url":"https://stenobird.com/podcast/smile-with-daniel-7904799/the-science-behind-noise-cancelling-headphone","show_page_url":"https://stenobird.com/podcast/smile-with-daniel-7904799","url":"https://rss.com/podcasts/smile-with-daniel/3010577","audio_url":"https://content.rss.com/episodes/390398/3010577/smile-with-daniel/2026_07_21_19_32_56_835ea6e8-dad2-45dd-8ef5-8b10211e2d91.mp3","summary":"Daniel put on his noise cancelling headphones on a plane and the engine noise just disappeared. He assumed it was thick padding blocking the sound. He was wrong -- in a really interesting way. Noise cancelling headphones do not block sound. They create more sound. And that new sound cancels the old sound out. You fight sound with more sound. Here is how it works. Sound travels in waves -- peaks and troughs repeating over and over. If you take two identical waves and line them up so peaks match peaks, the sound gets louder. But if you create an exact opposite version -- peaks matching troughs -- the two waves meet and the sound becomes much quieter. When the timing and amplitude line up very closely, they can come very close to cancelling it out entirely. This is called destructive interference. Noise cancelling headphones do this in real time. A tiny microphone on the outside of each earcup listens continuously to whatever sound is coming from the environment. A small processor analyzes that sound almost instantly and generates an opposite version of the wave. That anti-sound is played through the speakers so both waves reach your ear at the same moment -- and the sound is dramatically reduced. The system does this thousands of times every second. Without you noticing any of it. It works best on low, steady, predictable sounds -- the hum of an airplane engine, the drone of air conditioning, the rumble of traffic. Those are easy to analyze and cancel. Voices are much harder. Their pitch, loudness, and direction keep changing -- and often several people are talking at once -- which makes it much harder for the headphones to create a good opposite wave. The physical padding of the earcups is also doing something. It is especially good at reducing many higher-frequency sou…","meta_description":"Daniel put on his noise cancelling headphones on a plane and the engine noise just disappeared. He assumed it was thick padding blocking the sound. He was…","key_points":[],"chapters":[],"topics":[],"duration_seconds":486,"processing_state":"not_requested","actions":[{"name":"request_transcript","method":"POST","url":"https://stenobird.com/v1/public/podcasts/smile-with-daniel-7904799/episodes/the-science-behind-noise-cancelling-headphone/transcription-requests","description":"Idempotently request low-priority transcript generation for this episode."},{"name":"read_markdown","method":"GET","url":"https://stenobird.com/podcast/smile-with-daniel-7904799/the-science-behind-noise-cancelling-headphone.md","description":"Read the agent-friendly Markdown representation of this episode resource."}]}}