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DAM Broken tube?

When putting the KT90 output tubes in my new Rogue Cronus Magnum, I heard something rattling around in one of them. The other three are quiet. Does that mean the tube is definitely bad and I should not power the amp up?

I wanted to have it up and running in a couple hours.

When I picked it up at UPS, they had the box standing on it's side despite arrows on the box showing it should be laid flat and fragile symbols. When I pointed it out they said "Oh we don't do that", referring to following handling instructions on boxes.
bajaed
chuck
201 posts
 
Bajaed,

sometimes pieces of glass break in the the tubes. It does not mean that the tube is definitely bad. Do you see any physical damage to the tube structure? If you have access to a tube tester I would check it for shorts.
mofimadness's avatar
mofimadness
4,152 posts
 
I had that same thing happen a couple of times. The tubes worked just fine each time. It could just a loose piece of wire or structure that will rebond once it gets hot enough.
rodman99999
3,557 posts
 
Have it tested for shorts, before installing and powering up. Generally; there will be no problem. I would hate to use my power amp as a tester though. A shorted tube could get ugly, in your output stage.
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