Anybody: I've never messed around with treating CDs in any way. But to those who've found a difference (good or bad) treating them with markers, how exactly should I go about this tweak if I want to experiment? I'll burn 2 copies of a test disk, treat one, and compare the treated and untreated versions and post back here.
Albert: You say Krell confirmed your finding that "overhead halogen lights, shining through the Plexiglas lid of their MD10 CD transport, affected the bit stream to the D-to-A converter". This implies that they actually found a change in the measured datastream, and also that they controlled for any effect that such lighting fixtures may have on the powerline (presumably by measuring the data with the lights on, versus with the lights still on, but blocked from shining into the player). I hope that is the case, otherwise it seems to me no causal link could be established. Of course, as you also indicated, either way this probably has little relevance for the vast majority of disk-players made.
Mlsstl: You wrote "I've also compared the audio quality of CD's to bit-for-bit verified hard drive copies (which involve zero light of any kind) and heard no differences". While I can't do the bit-verification thing, using my Alesis MasterLink with its digital output fed to a Theta DAC, I've compared the 'live' playback of CDs with that of the same CDs ripped to the unit's internal hard-drive, and they don't sound the same (the hard-drive sounds better -- but both sound inferior to the same CDs played 'live' on a Theta transport).
Albert: You say Krell confirmed your finding that "overhead halogen lights, shining through the Plexiglas lid of their MD10 CD transport, affected the bit stream to the D-to-A converter". This implies that they actually found a change in the measured datastream, and also that they controlled for any effect that such lighting fixtures may have on the powerline (presumably by measuring the data with the lights on, versus with the lights still on, but blocked from shining into the player). I hope that is the case, otherwise it seems to me no causal link could be established. Of course, as you also indicated, either way this probably has little relevance for the vast majority of disk-players made.
Mlsstl: You wrote "I've also compared the audio quality of CD's to bit-for-bit verified hard drive copies (which involve zero light of any kind) and heard no differences". While I can't do the bit-verification thing, using my Alesis MasterLink with its digital output fed to a Theta DAC, I've compared the 'live' playback of CDs with that of the same CDs ripped to the unit's internal hard-drive, and they don't sound the same (the hard-drive sounds better -- but both sound inferior to the same CDs played 'live' on a Theta transport).