NBC Chimes

The NBC chimes, named for the radio and television network on which they have been used, consists of a succession of three distinct pitches: G3, E4 and C4 (middle C), sounded in that order, creating an arpeggiated C-major chord in the second inversion, within about two seconds time, and reverberating for another two or three seconds. The intervals of this progression are up a major sixth from G3 to E4 and down a major third from E4 to C4. The chimes were the first ever audio trademark to be accepted by the United States Patent and Trademark Office. Contrary to widespread belief, the "G-E-C" sequence is not a reference to the General Electric Company, which did not acquire NBC until 1986; however, GE's radio station WGY in Schenectady, New York, was an early affiliate of the NBC Red Network, and GE was an early shareholder in RCA, which founded NBC by creating it as a subsidiary.

The chimes were originally used as a cue for radio stations across the network to begin broadcasting their station identifications or local feeds. After their use as a formal network communications signal ended around the 1970s as the result of automation, the chimes have been used ever since as an audio logo or signature for NBC.

The chimes were originally conceived to help solve a problem inherent in early network radio broadcasting: the vast majority of which was live, rather than pre-recorded. At the top of each hour, any individual broadcaster (on radio, television or other broadcast band) must identify itself by their callsign and the name of the community where its broadcast license has been issued, in compliance with Federal Communications Commission (FCC) regulations. For example: "This is WHYY, Philadelphia." Therefore, it might seem efficient for a small radio network (three to seven stations, for instance) to accomplish this chore by having a single announcer "on the network," whose voice is transmitted to all the local stations, read the short list of local callsigns and corresponding communities for about ten seconds each hour, during an extended broadcast period. However, this practice becomes quite inefficient as a network grows, consuming valuable commercial airtime. Hence it was determined in early big-network radio days that this job, among others, had to be done locally, on a predetermined cue from the network itself.

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