At long last my UFO2.1 arrived this week.  I installed the tubes, swapped it out for the amp I had been using and after hooking everything up as I thought was correct, I noticed that I wasn’t getting any sound from the amp. I systematically tested various issues but still couldn't determine the problem. All the tubes glow when the amp is powered on but the current meters don't move above zero at all.  During troubleshooting I removed and reinstalled the tubes and I believe the first time I installed the rectifier tube I may have had it in the incorrect orientation, but it still glows when turned on.  I also reconnected my old amp and it is working normally.  Lastly, it wasn't entirely clear to me how to hook up the rca input cables.  They are hooked up 'outside'/'outside' and Ive tried both input selector positions.

Can anyone help troubleshoot this?  I'm hoping I'm just doing something dumb.

Thanks in advance !

Thanks a lot !  One of the internal 250mA 5x20mm glass fuses is clearly blown.  Will order a replacement and report back.

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FYI there are two separate circuits in a tube amp: a low voltage/high current circuit for the heaters, that makes them glow, and a high voltage/low current circuit for the actual music, that is measured by your meters. So having the tubes glow is a necessary, but not sufficient condition for your amp to work, as you have seen.

Hopefully all you need is a new fuse, but it is possible the rectifier itself is dead. If you don't have a set of replacement tubes I would encourage you to organize one soon, because you never know when a tube will go bad. And the best way to check for a bad tube is to replace it with a good one. Same goes for fuses.

Since all the tubes glow that indicates to me his rectifier is probably good, especially as when that particular fuse blows you get rectifier and tube glowing but no sound.

Still good advice to get back up rectifiers, Lord knows I have enough, about a dozen plus.

Great news!