A Short History of a Short Tone: The Dial Tone

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Did you ever pick up the phone in another country and miss our North American dial tone? When I spent three years abroad, I never got used to the various tones I heard in my ear, both the dial tones and the ringing tones. It seems like a small thing, but when I finally moved back to New York, the dial tone was one of the most comforting things I experienced!

So what’s the deal with our warm dial tone? Well, for starters, it’s not just one frequency, it’s two tones that modulate or “beat” together quickly between 350 Hz and 440 Hz. Most of Europe, by comparison, uses a single 425Hz tone.

In the old days, when operators used to place calls for people, there was no dial tone. But then, in the 1940s, when automated systems were developed, phone companies figured out that their customers were seriously confused by the lack of response/silence. You can imagine why, right? For eons, you’d pick up the phone and a polite woman would ask where you wanted to call. Now you picked up the receiver and nothing! To avoid this confusion, exchange systems started playing what they called a “comfort noise” – and like that, the dial tone was born.

If all this dial-tone-talk has got you itching to actually hear one, by all means, that is what we've loaded on the play bar below:

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December 2, 2010 - 10:19am
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