I had a Sheer Audio HA-006+ which is a Dynalo design (clone of the Gilmore Lite). While it was a great match for the HD650, It was not very good with the LCD-2. I could never find a solid spec on what it's output power at 50ohm was but I'm guessing it's well under a half watt. It just didn't have the guts to push the LCD-2. When I upgraded to a more powerful amp, they came alive.