How does a preamp die from sitting unused for a few months?

Many ways to look at this. Some failures are time dependent rather than use dependent. Some time has passed. Some failure are vibration or shock dependent. It has been moved so that could cause those. Some failures are caused by accidental mishandling which could have been caused by a cleaning lady or something unexpected during storage.

It could not be a failure but just a mispositioning. My DAC has pairs of RCA connections vertically and for some reason I tend to hook them up in horizontal pairs and then I have to figure out why one channel isn’t working.

Hopefully your failure will be fairly easy to diagnose.

I assume you mean the tubes aren’t lighting up. If multiple tubes aren’t lighting up that points to a fuse or powr problem. I’d open it up and see if there is an internal fuse.

If tubes are lighting up but no music, make sure you have all the connectiions correct. Make sure you don’t have a switch in the wrong position. then replace any tube that feeds both channels.

Jerry

makes no sense

something simple is wrong.

Probably died from loneliness. 

By checking the fuse did you do a visual inspection or did you do a continuity test with a multi-meter? A fuse may look fine but can be broken inside. If you don’t have a DMM replace the fuse and try again.

If that doesn’t work then maybe the power cord is not reaching the connector’s pins. To test this you need DMM. Put in a good fuse, open the bottom plate of the amp, plug in the female cord to the amp’s inlet receptacle (leave the other plug end unconnected from a wall outlet) and test for continuity between the cord’s hot plug and both tabs of the fuse holder. If there is continuity through the plug to the fuse holder tabs then the problem is inside, which definitely requires a service from the factory .

I'm guessing danager is probably right.  😉

I only visually checked the fuse and didn't do a continuity test with the power cord connector.  I'll try those next.

None of the tubes turn on.  I'm leaning toward the toggle power switch gave out as there is nothing remotely loose or broken off inside.  DHad does some great work!

If the rectifier tube is burned out would the rest of the tubes and power indicator light light up, or would all electricity be stopped at the first tube (here I'm assuming the rectifier is the first tube)?

Thanks, all.