Suitable tube preamp for pass labs x250

The CAT Ultimate mk1 is my brothers choice. Has only vynil and an an old tube tuner for source and no digital at all with early 70,s era klipsh speakers. VERY VERY SWEET. Another good option and in your price range. Can,t comment on CJ as I have not listened to any of there products. Cheers

Definitely go with a true balanced pre-amp. I ended up with a BAT VK3ix After my search for a pre to match my X150. I liked it better than Pass's own X2.5 pre.

Atmasphere or Sonic Frontiers?

When I had my Pass 250.5 I used it with a Thor TA-1000, absolutely superb match.

I would pay attention to what Tvad said. Great preamps won't sound so good if not matched properly with the input impedance of the amp. One fine tube preamp that can qualify would be the Joule LA150-MKii with the MU follower engaged (400 ohm output impedance set like that), should be able to drive most any load. Though it does not run balanced. THe Atma-sphere MP-3 is also quite good, but I'm not sure what the output impedance is - I think it is 600 ohms, which should work fine.