Early Sound Recordings
From my journal of April 11, 2011. In case you can’t read my scrawl: “I’ve read that early sound recordings were made with devices resembling phonographs: the music was played into a horn and the vibration of the horn was transmitted to a cutting needle, which was used to create an oscillating groove in a disc. The disc then became the master for a negative impression of it, which was then used to press vinyl playback disks. At this time the playback was achieved by running a needle along the grooves of a playback disk, the oscillations within the groove sending vibrations to a horn which amplified those vibrations into sound. I’ve always loved the symmetry of that process.”