I can't say it changes the sound of CD players generally--players are all different, and anyway you can't put tubes into a solid-state one to see if it changes the sound. (OK I lied, there was once an AMC unit you could do that with, and it was said to be an upgrade.)
Rolling tubes in a CD player does change the sound, though. I've owned two tubed players and they both sounded better (to me) with the right tubes. If that's what happens with a tube preamp (and many say it does) then I guess your answer is yes.
Rolling tubes in a CD player does change the sound, though. I've owned two tubed players and they both sounded better (to me) with the right tubes. If that's what happens with a tube preamp (and many say it does) then I guess your answer is yes.