Monday, April 05, 2021

The Great Black Out of 1965

When New York has black outs they can make history. Readers may remember the 2019 New York black out that left 73,000 New Yorkers in the dark if only for 5 hours. I can attest that it was hard to sleep that hot sweaty night in July of 1999 without power for the Air Conditioner for 18 hours... There was a similar black out back in 2003, affecting more of the North East, and back in 1977 they had one that stretched into the next day. But back in 1965 was the big daddy of them all: The North east black out affected 30 million people stretching from New Jersey deep into Ontario, Canada. The worst spots were without power for 13 hours. In New York City, six deaths were reported. More here.

History dives deep into the human story: people dying of carbon monoxide poisoning, and falling into elevator shafts; the apartments without heat slowly getting colder, the sardine tin panic inside stalled commuter trains and the parallel disaster control story at Con Edison. The story played out live on television on back up generators. But on an aircheck of 77 WABC from November 9th, 1965we also can hear evidence of a a subplot playing out on the radio band.

That evening between 5:15 PM and 5:27, just before the city was "sucked into the maw of darkness" as the New York Times wrote, there was a brown out.  The frequency of electrical power in America is standardized on 60 Hz. That means the voltage changes from positive to negative, and from negative to positive voltage 60 times per second. This process is literally driven by the rotation speed of  the rotor of the generator which is 60 cycles per second. At some point after 5:00 PM that day that speed began to drift. To quote Eric Alper [SOURCE]

"The station’s music playback equipment used motors that got their speed timing from the frequency of the powerline, normally 60 Hz. Comparisons of segments of the hit songs played at the time of the broadcast, minutes before the blackout happened, in this aircheck, as compared to the same song recordings played at normal speed reveal that approximately six minutes before blackout the line frequency was 56 Hz, and just two minutes before the blackout that frequency dropped to 51 Hz. "

 For reference, the drop from 60 Hz to 56 Hz is a 6.7% frequency shift and 51 Hz is a 15% shift and the rotational speed of the LP is directly affected by the speed change in the motor. This changes the playback speed, and therefore the pitch of the music in that recording. In western music an octave has a frequency ratio of 2:1 and is divided in to 12 parts (semitones). Pitch changes works on a logarithmic scale, so that 15 percent change does not change the pitch 15%. In fact the first 2% had already lowered the pitch by a full half-tone. This is eerily similar to the way that Varispeed was used in recording studios in the same era. There is a fun calculator here.

WABC disc jockey Dan Ingram was hosting his afternoon drive time show and playing the song Jonathan King's "Everyone's Gone to the Moon." It sounds noticeably slow, as did the ads that followed it. Ingram even remarked that the King record "sounds particularly slow" and "was in the key of R." 

After the ad break for hotel bar butter and the station jingle he again notes that "it's slow" and during the ad for Adams Sour Orange gum you can hear the pitch continue to drift.  "It sounds like it's running in slow motion." Then the song "(Up a) Lazy River"by Si Zentner starts to play (very slowly) and Ingram notes that the lights in the studio are dimming. The power continues to dip as they segue into news and the power is lost  about the time newscaster Bill Rice starts into the second story about the gubernatorial election... If you're interested, David Nye wrote a good book on the subject, When the Lights Went Out : A History of Blackouts in America.

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