This is the latest version. I bought it a couple of months ago. Like new condition come with box and manual. Come with PSU1 power supply. The reason why I sell it is I will go to another town for college soon and I don't want to carry many stuff with me.
Review link: http://www.head-fi.org/forum/thread/491295/review-graham-slee-solo-ultra-linear-headphone-amp
