Pls recommend a tupe pre under 2500 for my system.

I was going to suggest the BAT 3iX, but the VK-31 mentioned earlier has a better user interface (the 3iX is very basic), while also allowing tube rolling. I don't know what the VK-31 users for power tubes (the 3iX uses two 6V6 tubes), but I was quite surprised that most of the improvements in warmth came from replacing these tubes.

Joule Electra LA-100 or LA-150 would probably do the trick, if they can be found for $2,500

If you are trying to get the tube sound I agree with Darkmoebius
You cannot go wrong with the Joule Electra Preamps. At the price they go for here, they are a steal.

I cannot recommend the new Don Allen two tube linestage enough! It is the best I have heard, and that is including a First Sound preamp. Dramatic dynamics, air air and more air around the instruments, lots of detail, and tremendous bass with perfect pitch midrange, and it is only $800.00!

I have an Joule LA-100 and it's great. IMHO, a better choice for the OP's needs than any of the recent ARC preamps that I've heard. However, I'd try to go even further down the "tubey" road to get the result he's seeking. I suspect that an older Cary or C-J might do the trick. There probably will be some cost in bottom end control, however, if this is the chosen route. Ah, trade-offs.

Marty