Well this is odd. Everything has been fine all day. Went out and grabbed dinner, came back, and now I have almost zero sound out of the lead channel on the 6505. With the pre/post up around 3:00 I can start to hear some sound.
I uncabled everything, so the signal path is just guitar > amp > cab. All 4 power amp tubes are glowing, but I haven't looked at the preamp tubes yet.
un plug it, reseat all of the tubes. i had this problem with my verellen, reseating the tubes fixed it