Hi,
I can't tell about the pre-amp. But for sure, the CD23 is a really good value.
Of course, you could keep the Rotel CD player and use it as a transport. But considering the really low pirces of second hand CD23, I think it is more than worth a thought to get one. Just for your info, the 2 last ones offered on eBay have gone for 600 dollars and browsing around, you can find them for 650 dollars + shipping. YOu'll then have one box less to place on your rack and you'll be the proud owner of a dCS DAC, which is something among the best that have been built. According to all Arcam "fans", the CD33 and CD36 are really good players... but they all have some nostalgia for the CD23.
What's good about the CD23, is that it is a really well balanced player. Soundstage is amazing for the money : as well in width as in depth (keep in mind this won't necessarily apply if you have a huge rack in the middle of your speakers). I love the low dry bass it offers (some other player/amp/speakers combination have a bass that is so present that it litterally eats up the medium range ! Some even the high range...) and the detailed, but yet warm sound it delivers.
It may lack a little of fastness... but isn't that more natural ? And doesn't this allow a fatigue free audition for hours ? I think it does... but of course, everyone might have different thoughts on this.
So my advice would be as follows : try to get someone who can arrange an audition of a CD23 and compare it to your Rotel CD player. Then decide for yourself :-) But I am convinced that you'll hear the improvement provided by the CD23.
Regards.
Penguin HiFi