WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
Building, troubleshooting and testing of these amplifiers should only be
performed by someone who is thoroughly familiar with
the safety precautions around high voltages.
My Amp was working fine, but last night I got hum from both speakers and no audio output. The hum is present at all volume levels above zero and does not increase as the volume setting is increased. I would appreciate any suggestions or pointers
I think you could do a lot of damage very quickly to your 5. Even though I've been a DIYer for many decades I'll only change the tubes in my Ref 3. Find a QUALIFIED tech to work your on your baby or send it back to ARC. It might cost you several hundred to get it fixed, several thou if you start yourself.
In general I agree with Steve. However you could do some basic trouble shooting. This assumes that you have the knowledge and skill needed. The 180v supply is nothing to mess with. The capacitor bank can hold voltage for a long time.
Look for the correct voltages from the power supplies. I think that the values are marked on the board. You might be able to fix a bad 317 / 337. I would not mess with the 180volt supply, too many possible parts to go bad. Are there any clear signs of blown components?