Podcast:99% Invisible Published On: Tue Nov 29 2016 Description: The NBC chimes may be the most famous sound in broadcasting. Originating in the 1920s, the three key sequential notes are familiar to generations of radio listeners and television watchers. Many companies have tried to trademark sounds but only around … Continue reading → Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to ad-free new episodes and get exclusive access to bonus content.