SUMMARY
The famous "Armistice Day recording" from November 11, 1918, is not an audio file but a photograph created on 35mm stock. An American crew used a harp galvanometer, a device employing light-sensitive material and a tuning fork clock, to record the sound of artillery fire. The resulting image, titled "The End of the War: A Graphic Record," shows the transition from active shelling to silence, with the most widely shared version being an excerpt highlighting this contrast. The apparatus automatically developed and fixed its output, allowing for rapid analysis of gun locations.
TAKEAWAYS
The "Armistice Day recording" is a photograph, not an audio recording.
It was made on 35mm stock using a harp galvanometer and a tuning fork clock.
The image captures the shift from artillery fire to silence on the front lines.
The widely circulated version is an edited excerpt emphasizing the contrast.