sorry for this probably dumb question....   but do the valves on one of these amps get very hot? I would be concerned about delicated little fingers getting burnt when I am not looking...

Hi all   first time poster so please be kind ;-).   I have recently entered into the world of cans with a purchase of a pair of 650s. this is due to the new arrival needing sleep or something... anyway I have a Marantz Nr1501 which seems to have a reasonable phone socket (or at least the...