Happened to me with my Phi 200 once. Check the fuse in the back of the amplifier.
VAC Phi 300.1 won't power on.
Upon plugging in my VAC Phi 300.1 power amplifier I heard a soft pop and then it went completely dead. This was after I had removed and cleaned each of the 8 output tubes. I've contacted VAC but as it's the start of the weekend I wonder if any VAC users have encountered a similar situation. I live in Alaska so sending it back is a massive ordeal.