heisenberg wrote: > Some slight differences in the way the LPs were pressed, or handled, or > packaged etc., contributed to the variation in the sound quality. I > guess the technology was immature back in the day, coupled with shoddy > quality assurance etc. > > I wonder if the same consideration holds true for the modern pressings, > or if the technology had advanced to the point where there is much more > reliability in terms of the quality assurance?
The biggest variables in record pressing comes from two factors - where in production run was a particular copy pressed and the purity of the vinyl. The master disc is used to make multiple stampers which, in turn, are used to press the records. Because the stamping process is physical, a stamper may only produce perhaps 1,000 records before it is too worn and has to be replaced. Think of a sharp knife which progressively dulls as it is used until it needs to be resharpened. When you buy a record in a store, it is sheer blind luck as to whether you get a LP that was stamped early during the production run with one of the first stampers made from the master or whether you get a copy from the end of the production of a stamper made toward the end of the master's useful life. There is nothing about modern LP production plants that has fixed the issue of progressive wear during the manufacturing cycle. (In fact, I believe most LP factories use machines that were made 30 or more years ago.) One only hopes the pressing plant cares enough about the quality of their product to trade out stampers and masters often enough to keep audible differences minimal between the start of a run and the end of it. ------------------------------------------------------------------------ mlsstl's Profile: http://forums.slimdevices.com/member.php?userid=9598 View this thread: http://forums.slimdevices.com/showthread.php?t=98603 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/audiophiles
