krell kct, pass labs xp 10 or 2.5, spectral?

Hello All, my current system is:
* B&W 801Nautilus (not diamond version)
* MIT speaker cables
* Mcintosch MC500 power amp
* Accuphase DP500 cd
* Levinson 38 preamp

The sound is not bad at all, never unnerving but it just does not emotionally involve me enough, the system doesn't dissappear enough and seems a bit slow. (I had active speakers before). I would like to hang on to my power amp and cd player (which I know are rather warm sounding both).
I just got the speakers, so could another preamp do the trick? I had Mcintosh c46 preamp in the same system and it sounded more open but more coloured? as if the same sauce was added to each music cd?
I can buy (all used) a Krell KCT for 2800 euro, a Pass Labs XP10 for 2700 euro, or a XP 2.5 for 1500, or a spectral dmc 12 for +-1400... O yes and a Nagra PLP for 4000 euro...
Which would u recommend to make me feel drawn emotionally into my music, where there seems to be no more system? I read many reviews but next to that there is also imput impedance that plays a big role? Please help. As all my options are used market ones, I dont have too much time to chose :)
THX guys!