there is no black and white answer to this question. one of the functions of a preamp is to act as a buffer between source components and amp. in other words match impedence. the same issues will occur when you go direct and depends on how good the audio setion is in the CD player.
CD player connected directly to Amplifier?
I've been noticing some CD players which can be connected directly to the amp; in many models, its the recommended way to play them. I've never done this, but it seems like a good way to go assuming one has a nice high-end cd player equipped for such a task. I see the obvious advantage of foregoing the expense of a separate preamp, especially in a combined HT/2 channel rig like my own. Is there an obvious advantage in performance? Anyone have any thoughts or experience with this method?