C.d player with built in Pre amps i.e Wadia

I also use the Opus 21 and still prefer it through a pre.

To clarify my prior response, I have the GNSC modded Opus 21 as well and its a wonderful CDP. When I first got it, I used it as a pre and it did an admirable job; however, inserting a pre into my system really allowed the Opus to do its job as a CDP. The sound stage opened up, etc. Again, this is all system dependent. You have to consider input/output impedences, gain requirements, etc., just as you would in selecting any pre. In MY system a separate pre works better. In yours, using a CDP as your pre may work wonderfully. You will just have to experiment.

Krell made the KPS 25sc which was a pre amp and a CD player and its a fantastic unit. It has a Anolouge vol control and complete pre amp functions!