Question

As you listen to a vinyl record, how does the speed on the needle on the record change as the album progress (the needle move from the outside in)? How compensations made (if any) for this?

Answer 1

If you think of cutting a record as sort of playing a record in reverse, it'll make sense. Instead of the needle being vibrated by the record groove, in cutting, the needle is vibrating in order to cut the grooves. So, as the platter spins, and the cutting needle moves in, it vibrates at the same rate, even as the circumference become smaller, and a revolution is quicker. So when you play it back, everything is as it should be, speed-wise.What does happen though, is that the information gets more and more compressed as the needle moves inward. This is because, again, the needle vibrates at the same rate, while the vinyl "slows down" as you get closer to the center. The faster the disc turns, the more "spread out" the information is, and therefore, the more information can be packed in.