tube vs ss for pre-amp.

am considering changing pre-amps. system now is gfp-750,marsh a400s,marantz sa-1,aerial 10t.low to moderate volume. adcom pre. is used in passive considering roque or audio research tubed. not sure adcom isn't about as good as i can do in this sys.,but am curious about tubed dealers in my area for auditions( there any degree of predictability on what i might hear with this change? also curious about black gate mods for the adcom,but have been unable to contact modifier for this mod only effective in active circuit?any help is appreciated.
The gfp750 mod does only apply to the active circuit.
Happy Listening!
The Eastern Electric MiniMax tube pre for about a grand. Galen Carol Audio,, can even let you try it before you buy it. A giant killer of a unit.
I'm using an ARC LS 16 with my Marsh A400s through some VMPS speakers and love it. Very smooth and transparent sound. The Audio Research does not lose any dynamics or extension at the frequency extremes. If you are looking for tube euphonics you'll need to try something else as the ARC has just a taste of it. I tried a Cary and it had a lush midrange but dynamics and detail were lost. The ARC loses no detail and is Very smooth. Wished I would have tried a tube preamp years ago.
What kind of change are you looking for, or what do you feel you're missing now?
If you can swing it, the Hovland HP-100 sounds great with the Marsh. I used to run these into B&W Nautilus 803s & 802s.
Here's a nutty thought -- how about the Marsh P2000t preamp? Should be some nice synergy there.