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This maybe https://www.ntu.edu.sg/eee/news-events/news/detail/-noise-cancelling-device-by-ntu-eee-scientists-halves-noise-pollution-through-open-windows https:/

• ghusbands 2y ago
  That's active electronic noise cancellation - there have been many of those described and very few delivered over the past thirty years. Presumably because it's the sort of thing that is angle-sensitive and hard to set up and maintain. The thing I saw was just a pane of glass or plastic with large round holes in it to attenuate/dissipate sound waves while allowing significant airflow.