Linear Tube Audio they make a great preamp get it with the max Lundahl transformer ,order with the 6SN7 tubes , and it also has I believe 12at7 tubes or similar 9 pin tubes ,it was originally designed by tube guru David Burning
then improved upon again ,it has several stages of regulation ,clarity best CMR capacitors you can dictate the sound with these tube types and at around $6k retail
will compete with anything in the $10 k range check itout , Mike at Audio Archon
will give you a fair price and check out all the excellent reviews ,use a good quality power cord and high quality tubes , vintage tube service, or Brent Jesse recording
for true NOS tested matched tubes.