Pre-emphasis on (some) CD's

[james]

http://www.tnt-audio.com/vintage/pro ... 1_e.html

http://www.tnt-audio.com/vintage/procr ... 2_e.html

The article explains that some CD's from the early days of CD (up to the mid 1990's) had pre-emphasis applied and it is necessary to remove this when transferring them to a hard-drive. The only way to discover if the correction is needed is to run test programs on the original CD.