Budget preamp recommendation...besides Schiit.

Townshend Allegri+
I got one new directly from Townshend for cheaper than advertised. 
 

I concur with all the reviews already written about this preamp. 
 

https://the-ear.net/review-hardware/townshend-allegri-passive-preamplifier/
 

https://www.theaudiophileworld.net/2018/05/the-townshend-allegri-real-world-review.html?m=1
 

https://www.hifipig.com/townshend-allegri-passive-preamplifier/

Nelson Pass Nutube Korg B1.

Such a lot on offer for such a little outlay.

Khozmo passives or Hattor passive/active, both made with high quality attenuators and parts plus huge selection of options between the two "sister" companies (i.e., same owner/manufacturer - Hattor is to Khozmo what Lincoln is to Ford).

What’s wrong with Schiit? I have found that the Freya+ is quite responsive to different tubes, thus giving the ability to tailor the sound effectively.

I second Quicksilver or Conrad Johnson .   CJs are tough to find at a reasonable price though.     

The preamp is the most important component in your system, choose carefully