Hi. I feel really bummed out and feel stupid. I accidently plugged in my 4x12 cabinet, Marshall MX, into my bugera 333xl amp line out jack. The amp popped with a puff of smoke and shut off, it won't turn back on. Did I ruin my cabinet and amp? Is it fixable? How much would it cost to fix?
You likely killed just the amp. Take it to a local tech to get a quote for the repair.
If it was just a pop it might just be a fuse and some caps. Risk the loss of the transformer though.

I agree get it to a tech. If just a fuse or caps should be easy for him. If the transformer, then that will be spendy.
You've likely blown the output transformer up. For an amp like a Bugera, that's probably not worth fixing.

Buy a new amp.
Quote by TheSennaj
And well yes, I'll enjoy the carpal tunnel and tendonitis, because trying to get one is clearly smarter than any word you have spoken thus far.
Quote by T00DEEPBLUE
You've likely blown the output transformer up. For an amp like a Bugera, that's probably not worth fixing.

Buy a new amp.

+1 unfortunately
WTLT 2014 GG&A

Quote by andersondb7
alright "king of the guitar forum"

Quote by trashedlostfdup
nope i am "GOD of the guitar forum" i think that fits me better.

Quote by andersondb7
youre just being a jerk man.

****** NEW NEW NEW!
2017-07-07 2017-07-07 Update and a Chat On Noise Constraints *** NEW FRIDAY 7/7
2017-04-13 RUN AWAY from COMPUTERS!!! TCE? RANT ALERT!!!
2017-03-02 - Guitar Philosophy 1001- Be Prepared For the Situation (Thursday 2017-03-02)
2017-02-21 How to Hot-Rod the Hell of your Stratocaster for $50! (Tuesday 2017-2-21)
Resentments and Rambling from a Guitar Junkie
---> http://trashedengineering.blogspot.com/
Your speaker cab is fine, the amp not so much, as has been said take it to a tech for a look over, maybe you got lucky and its an easy fix.
Going from the line out to a cab? Actually nothing should have happened, My guess is you have one of the older pre Infinium Bugeras and it was just a coincidence that the magic smoke escaped at the same time you tried to supply your cab with 3v, .010mh line level power, (not enough to shock a piss ant) Give or take of course for those that know anything about amps, how they work or how to repair them, Granted I'm not a Bugera expert but I doubt they put the line out circuit on the pre or power amp side of the circuit, Meaning that smoking a transformer is highly unlikely, Pop, smoke and shut down? I'd guess a capacitor. But then again being a Bugera? Fried the PCB, Throw the amp away, Cabs fine, I've actually been screwing around with an 09 first gen TriRec Infinium, Had it apart last year for a bad internal switch/relay, easy fix and found two questionable 12ax7 on the preamp side, replaced them with some old but good Slovtek's out of my Kustom, So 9 out of 11 valves are still the stock Bugera's and its still running strong, Its an experiment, don't judge guys,