For around $1,500 .. Linear Tube Audio..
The Microzotl preamp is getting some extremely good reviews, by people who are used to much more expensive equipment..
Very Highly Recommend..
https://www.lineartubeaudio.com/products/mz2mz2-sI’m using a,
Decware (CSP3) preamp/headphone amp.. The only complaint with my preamp is no remote control for volume.. But rolling tubes can be useful while trying to match to your equipment and taste..
I bought the CSP3 to use with my ZMF headphones , recommend by Zach of ZMF headphones.. I was hoping that the CPS3 would be high enough quality to replace my Odyssey Candela .. I placed the CSP3 into my system feeding my 2 channel Odyssey Extreem +++ SS amp..!! It sounded so good that , I sold the Candela, and bought a Decware amp as well..
http://www.decware.com/newsite/CSP3.html