ARC Pre + which SS amp?

Rwwear, can you be more specific as to which Krell it is, what speakers, etc?

I use LS-25 with Pass Labs X250.5 and I think this combo synergizes extremely well. Also, there is a nice difference between running ARC balanced or single ended. Balanced is always better. I tried.
I see you use B&W speakers.
FWIW, I found the X250.5 with LS-25 to work great with my B&Ws.

I second DNA-500.
However, one note of caution, with the 500, the input impedance of this amp is rather low at 10kohms, so careful matching with a tube preamp is a must. You can't have too high of a gain or you won't be able to finely adjust the volume.