So I just bought a 1989 JCM 800. Plugged it into my new cab, a Berhinger 4x12 (it was $50!)

So basically, I had the amp's selector switch at 4OHM, and the cab's mono is at 16OHM. So anyways, 10 minutes in, the amp smokes, blows, and shuts off. Won't turn back on.
1. What happened?
2. What needs to be fixed?
I hope this is trolling...

Anyway if it isnt
you dun goofed.
You probably fryed the output transformer and tubes

take it to a tech immediately..
yah... possibly you should always match the ohms...

Just take it to a tech they'll be able to gauge the damage.
That's my plan.
Also, for who ever owns a JCM 800, the impedance switch has 3 positions. 4OHM, 8OHM, and a blank position. Is the blank position the 16OHM one?
The third position should be 16 ohm, yes. You'll be pretty unlucky if you've done the output transformer but smoke is never a good sign. You need a tech to take a look at it.
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Have you checked the fuse at all? It maybe that simple, if your very lucky. If not you'll be shelling out $250+ for an OT and about $80 for new tubes. This will probably not include labor, and that will run you probably another $100-$200. And from what I know yes the position with no ohm listed should be your 16 ohm, but don't quote me on this.
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