Thanks steve. This will be useful as we continue to occasionally come across old CD’s with pre-emphasis.
It’s important to note that some of these CD’s reveal their PRE-EMPHASIS flag only in the sub-code of the disc, not in the TOC as they should, and the majority of CD rippers only look for the flag in the TOC (apparently there are legal problems with software applications accessing the sub-code). Such is the case, for example, with Boz Scaggs - Silk Degrees, CBS Japan 35DP-20 which I acquired recently.
Obviously we need to be diligent about when de-emphasis is actually needed!
Here are two useful lists of pre-emphasized CD’s https://forums.stevehoffman.tv/threads/pre-emphasis-list.121188/page-16#post-9740531 http://www.studio-nibble.com/cd/index.php?title=Pre-emphasis_(release_list)
Or if you like to determine these things, yourself, CUERipper for Windows (part of CUETools) can read the disc SUBQ and reveal pre-emphasis flags there.
Or if you have a Linux installation, cdda2wav can also read the SUBQ.