Your very best value is a VTA SP-13. It has the same circuit as the SP-14, but is about half the price of the SP-14. The SP-14 is the same thing as a Don Sachs preamp (list price at $2500), but in a plain utilitarian enclosure. The SP-13 is $595 in kit form and $760 assembled and tested. Get the kit. You'll get enormous satisfaction, learn a great deal and be much more involved in your system in doing so. Best value in audio.
https://www.tubes4hifi.com/pre11.htm#SP13
Upgrading preamp. Best for under $1K
I am planning on upgrading my preamp and was wondering what would be the best preamp for under $1K. Currently have the Rotel RC-995 with a B&K ST2140 amp and Vandersteen 2ci speakers. I like to stay with SS unless their is tube pre in that price range.