For Digital Drumset, Video Synthesis and Octophonic Sound Projection
“Visualize the fineness of a record groove, and then consider that it combines two distinct channels of information, each with completely different modulations. Some of the signal modulations in the groove are on the same order of size as a wavelength of light, which means the stylus has to “read” a signal as small as a millionth of an inch…
For the half a mile or so of record groove per LP side, the stylus must precisely trace abrupt changes in the direction of the undulating groove, sometimes traveling at speeds several times the acceleration of gravity, without ever losing contact with either wall or blurring together the modulations.
Groove friction heats the stylus up to 350 degrees Fahrenheit and the groove vinyl momentarily liquefies each time the stylus passes over it. (This is why one should let a record rest for at least 30 minutes before replaying it, and preferably for 24 hours.)
Even though the cartridge tracking weight is commonly set at only about 1.5 grams, the entire weight is supported on the minute edges of the stylus. As a result, the downforce applied to the groove on a per-square-inch basis is several TONS.
Combine these extreme conditions of weight, heat, speed, and need for exquisite maneuverability, then add in the scale of environmental vibrations that interfere with the stylus as it retrieves the music from the groove, and it’s extraordinary that ANY music (as opposed to noise) is heard through an audio system.” Laura Dearborn