No sound in either channel (resolved)

For all of the connections on the octal socket, I would pull a little more wire through them and wrap it around the socket.

The 219V at terminal 9 makes me wonder if one of the black wires in the amp is loose. 

If you happen to have a spare 6080/6AS7G sitting around, it wouldn't hurt to give that a shot as well, but having both 7 and 9 so far off in different directions would tend not to suggest a bad tube.
 
Good morning PB. I rechecked the black wires and couldn't find anything that was loose, but I resoldered them just in case. I don't have a spare 6080 at the moment so I can't test it. However, my 6080 tube is a bit loose at the base (the metal part at the bottom), if that means anything. Rechecked the voltages and got the same readings at 7 and 9.

On another note, I actually remember hearing a noise the first time I turned the amp on a week ago. I'm not sure where the noise was coming from but it stopped working shortly after that. I had a spare 6080 tube (but later sold an amp with the tube) and tested that but by that time the big board stopped working. Do you think maybe the 6080 tube was the one making noise and is it possible that it messed up the big board?

I will buy a spare 6080 for testing.
 
Is one 3K resistor getting much hotter than the other?  You can run the amp for about 60 seconds, then shut it down and wait about 20 seconds, then safely touch the resistors.

The disparity in the voltages would make me wonder if both resistors would be cold. 

 
So 219V DC across a 3K resistor will dissipate 16W.  That won't be enough to completely blow the resistor immediately, but it will get very hot in a hurry.  Since it isn't getting hot, this is almost certainly an issue of loose connections in the amp not properly conducting and giving anomalous readings.
 
PB, I just resoldered every joint in the amp and paid close attention to the connections in the octal socket but I'm still getting the same readings.
 
Hello JimbO and Paul. Paul correct me if I am wrong. In the above photo it appears that the 10K cathode resistor on the left side is connected to B+ which is flowing through it to the output cap which is shorting to ground through the head phone jack?? That resistor should be connected to the same ground point that the resistor on the right is connected to?? Don't plug your phones in!

Chris/AB2KH
 
JimbO , Yes. Disconnect the left side resistor from the red wire, move the red wire out of the way, or better yet remove it from the terminal lug altogether, It has B+ on it. Connect the resistor lead that you just disconnected and solder it to the same point that the resistor on the right is connected to the black wire (ground).  That should be the non speedball configuration. (Disclaimer) Please do not do any fufther testing of your amp until Paul (whom is the official expert on this Bottlehead Forum) confirms that this is correct, I do not want to be responsible for injury to you or damage to your amp.
Chris
 
I would test it with a different 6080, though it would be super unlikely to get one with two bad halves.  Can you confirm that it doesn't say 6082 on the glass?
 
Sure. My new 6080 comes in tomorrow. Most of the markings have faded away so I can't read it. The brand is National. Here are some pics of it.

https://imgur.com/a/DLFl115
 
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