I'm selling mine to fund a portable but anyone looking for a budget amp for the HD650 should look at the Yulong A800. Its the perfect combo. You can find it in the US on ebay or from Grantfidelity; both are shipped from Asia.
Here are some quick impressions: "This amp is stellar. IMO, It easily beats the O2, E9, P4 and Asgard.I felt the Asgard was pushing too hard and sounded forced. The Yulong A800 is effortless. The Just Audio AHA-120 gives it a run for its money, but at its asking price, the Yulong A800 is clearly a bargain. It has tons of power. Out of the ODAC, you're not even at 9 oclock and getting too loud for the HD650 (though I tend to listen lower than many). Out of an IPOD line out, it's more like 11 oclock and sometimes that is too loud. (And thats with classical!) Its definitely a solid state amp, with lots of clarity and neutrality. Its dynamics are stellar. I have no idea why we haven't heard more about this amp. I'm going to try a couple high end portables but so far I'm coming right back to the Yulong A800 if they don't knock my socks off. The only reason I didn't bring it home from the office is the pain of cords, etc. But my ears have been addicted to this amp. And while great with the ODAC, I find it a killer combo with an ipod classic line out. I think I even like it better my ipod classic than with the ODAC."
Several AHA-120 owners said the difference between the AHA-120 and Burson HA-160 were negotiable. I would love to compare this with the Burson HA-160. I've drooled over the Burson. From the descriptions I've read of how the HA-160 sounds, I think Yulong was going for that kind of sound.
Edited by imackler - 11/5/12 at 6:08am