I've owned a few tube preamps. The TAD 150 Signature is one of them. It's a nice preamp, warm, musical. It just sounds right. For its price point it's hard to beat. I now have a VTL 2.5 which is also a good preamp within your price range. There's a Juicy Music Blueberry that's nice as well. Conrad Johnson and Joule come to mind but I have not tried these.
I'm sure other members can offer other choices. Best wishes.
I'm sure other members can offer other choices. Best wishes.