Linear Tube Audio MicroZOTL MZ2 headphone amp designed by legendary engineer David Berning. Comes with upgraded LPS power supply for added depth of soundstage and silent background. Unit features upgraded Tung-Sol 6sn7GTB and Tung-Sol 12AT7 6201 tube compliment; a nice step up in Sonic’s from stock Chinese tubes. Amp works perfectly… a few superficial marks on the face. The plexiglass top is near flawless showcasing the intricacies of the design. Cosmetics: 8.5/10, Functionality: 10/10. My favorite thing about this unit is its versatility in that it has two speaker jacks, allowing it to serve as a low wattage power amp (1 wpc). I have used this to drive my vintage Klipsch Forte 2s with stunning results. Filled my entire home with lush, tubey goodness…tremendous instrument separation. Ultimately what sets this amp apart is the DEAD-SILENT background. It’s just non-existent; that’s the transformer-less technology for ya…a stunning achievement and why this design received the reviews it did. I was using this MZ2 in my office as a headphone amp while also driving a pair of ADS L300C (88 db?, hardly high-efficiency) and it still could drive you out of the room. This unit is now discontinued and will become a collectors item; the only reason I’m passing this along is my wife and daughter surprised me with an MZ3. Continental US only.