I'm selling my SSMH + extra tubes because I'm trying to get some funds to upgrade. I am not the original builder and I cannot remember who I bought this from. But it works great and drives my HD580's great. It comes with the power adapter and a bunch of tubes (3 of 12AE6A and 2 of 12FK6). The amp is working fine, however you do need to fiddle a little with the front tube until it gets the right position. and as long as you don't move it too much, it'll be stable. That's the only problem, which is why I'm selling for so cheap. I'm sure anyone with DIY experience can even replace the front tube socket if they wanted to. $65 shipped CONUS.