Given your response as to what you are hearing, I advise the following:
One, get the dedicated circuits. This WILL help with the bass. It did with my stereo. Plus it provides a blacker background, which allows the music to come through cleaner. (I have the Revel Studios, which are pretty similar to your Wilson Sophias, so I think it will do the same thing for you.) You might also try to adjust the room accoustics. (Sometimes this is not possible, as there is the W.A.F. to consider, as in my case!)
After having done that, listen to stereo again, and see if this works. If not, I would consider replacing either the source (your Wadia) or your pre/pro. (Note: I am not a huge Krell fan, but if you like the sound of their amps, stick with it. me, I am a Levinson fan, so what do I know, huh?!)
If it were me, I would replace the pre/pro, but that would mess up your HT setup, wouldn't it?! I would consider a dedicated two channel preamp, possibly a tube one, as they can inject some life back into the music.
Or..... You can try an analog setup and see if that is what you are missing. (Yeah, I'm harping on that again. If you haven't tried analog (seriously tried it), and you are serious about having the music sound special, give it a shot. It really turned me back on to listening to music again.)
Anyway, my two cents worth. Good Luck in your quest!
PS If you want to try a different source, I recommend the Resolution Audio Opus 21. It is the best, most analog sounding CD player I have heard, that is reasonably priced. (Reasonably priced for us Audiophiles anyway.)