I have the mk1:

https://www.gearspace.com/board/lach...el-583s-g7317/

not mk11, but I think by far this is my most versatile preamp:
583s MK2 500 Series Tube Mic Preamp

The three others I have: (Avedis MA-5, Heritage Audio 73JR, and APA Juggernaut).

rsp