best preamps

There are some great suggestions listed. Here are a couple more -  forgive me if they have already been mentioned.

Conrad Johnson Evolution 20 - Discontinued  - used market
https://conradjohnson.com/vintage-conrad-johnson-products/

Rogue Audio Hera 2 - Discontinued - used market
http://www.rogueaudio.com/Products_Hera_Front.htm

Ypsilon Electronics
http://ypsilonelectronics.com/pst-100/