First tube preamp recommendations (under $5k)

Considering this being your first go around at a tube Preamp, the Schiit Freya+ would be a great place to start. The unit can be run in tube, passive or buffered mode. It costs around a grand brand new and has great resale value. Starting here may be a beginning as well as an end point. 

@decooney
I am using nos sylvania 6SN7 GTA from the 50's, not the vt231.  
Love the sound, these are reasonable and readily available.  
Even with the stock sovtek rectifier but the sound  did improve with a nos mullard rectifier.  

I have used the deHavilland Ultraverve 6sn7 based preamp for at least 10 years.  Over that time I have had the preamp's designer, Kara Chaffee, mod it with Dueland silver point to point wiring and Dueland premier capacitors. I run this preamp into an ss Bryston 14b3.  The 6sn7 tube you choose has a huge effect on the overall sound of your system...as much, or more, than cable choice.  I like jazz and I have, for the time being, settled on the RCA 5692 red based 6sn7 for my "sound signature".  I highly recommend the deHavilland...a bargain new or used!

I have used the deHavilland Ultraverve 6sn7 based preamp for at least 10 years.  Over that time I have had the preamp's designer, Kara Chaffee, mod it with Dueland silver point to point wiring and Dueland premier capacitors. I run this preamp into an ss Bryston 14b3.  The 6sn7 tube you choose has a huge effect on the overall sound of your system...as much, or more, than cable choice.  I like jazz and I have, for the time being, settled on the RCA 5692 red based 6sn7 for my "sound signature".  I highly recommend the deHavilland...a bargain new or used!

@invalid - I am NOT pushing my services in these threads.  Probably not one person posting on these threads could afford my products and services.  I have offered to help people out by offering to build them a superior product that they can afford and cannot find anywhere else.  If you think you can find a better product have at it.  But for me to take my time to build a point to point wired product using the parts that I offered for around $2K good luck finding anyone to do that for you.  I make about $200 building something like that.  I have been a member here for 20 years.  I have taken my personal time to travel to a homes to help them on my own dime.  I am happy to do that for people.  I have repaired more components than you have even heard.  You are a member since 2016.  You have one transaction on Audiogon. You don't even have your system listed.  Maybe instead trying to call someone out, you should look to their experience to achieve better results in your system.  I bet I have more money invested in parts then you have in your system.

@pfeoffer - excellent choice in a preamp.  Upgrade a few resistors and the transformer plus add an AC filter choke and your unit will sound even better.

Happy Listening