It's more than just quietness between tracks. Many components always produce a certain amount of background noise, like preamps and amplifiers as well. There is something called a noise-floor, the point of audibility for this type of noise. Record players have a noise-floor too. The lower the noise-floor, the more actual musical information surfaces, as the more delicate less audible details, resonances and so forth, get wiped out by a more prominent/higher noise-floor. A turntable's noise floor is determined not just by surface noise, but also by environmental noise coming across the air or through the feet/stand, noise from the motor, from the belt-and-pulley or idler-wheel or whatever system, and from its own bearing and plinth design's ability to cope with these various sources of noise. A turntable with an especially black background reduces the noise floor to a greater extent than one with less black backgrounds, which translates into more detail and various other types of information, which means it is audible (by not being there) during music as well. So "quiet between tracks" doesn't quite cover it. Hope this helps!!
