The famous three-note NBC chime (G-E-C) originally consisted of seven notes, which were proved difficult to play correctly, so the sequence was shortened to five, then four, and finally three notes. The notes were manually played on four-bar chime sets manufactured by the J.C. Deagan Company of Chicago. Additional reports state that the initial sequence was G-C-G-E-G-C-E, which became G-C-G-E and then just G-E-C (which, contrary to popular belief, were not meant to represent former parent company General Electric Company's initials (GEC)). November 29, 1929, is sometimes reported to be the date that the three-tone sequence was adopted, however, the longer intervals were still in use until 1931, according to surviving network recordings. User Powernugget has found the audio recording of the original chime as of 3/25/2022. You can view it here: http://www.theradiohistorian.org/audio/NBC_chimes_and_WGY_ID_1929.mp3
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