Hi. Had the same issue with my Ref3 LE a couple months ago. I was listening to some music one night and suddenly nothing. I looked at my Classic 120´s and all the tubes were lit. I looked in the Ref3 and my vintage Tungsol 6550 black plate is dead. Removed it put it on my Hickok tube tester and it tested strong as brand new????
I replaced it with a brand new SED 6550 I had kept as a spare. The tube would not light up at first but did a few minutes later. It stayed lit for a few hours and then went dead the same as the Tungsol.
I sent an email to ARC detailing the issue. They were very helpful!! They asked me to send the unit to them as there is a major problem in the power supply.
Reading your post I am glad I did not. Anyway, the problem was the solder joint on the tube socket pins were cracked which cause the tube to go on and off intermittently.
I took the unit to a tech I know and he’s redone all the cold solder joints he could find (including the problem socket) and all is well now.
Having sent the unit back to ARC from Canada would have cost minimum $150.00 each way plus a new tube which I didn’t need and they would have missed the cracked solder joints on the tube socket. I got the work done for $80.00.
I replaced it with a brand new SED 6550 I had kept as a spare. The tube would not light up at first but did a few minutes later. It stayed lit for a few hours and then went dead the same as the Tungsol.
I sent an email to ARC detailing the issue. They were very helpful!! They asked me to send the unit to them as there is a major problem in the power supply.
Reading your post I am glad I did not. Anyway, the problem was the solder joint on the tube socket pins were cracked which cause the tube to go on and off intermittently.
I took the unit to a tech I know and he’s redone all the cold solder joints he could find (including the problem socket) and all is well now.
Having sent the unit back to ARC from Canada would have cost minimum $150.00 each way plus a new tube which I didn’t need and they would have missed the cracked solder joints on the tube socket. I got the work done for $80.00.