So I have this HUGE bassman head and cabinet. Problem is they won't work. I've replaced the tubes, fuses, and nothing works, the head turns on, the tubes warm up but I get nothing from the cabinet. I plugged my phone into the amp and I heard the music I was playing on my phone very faintly through the head, but barely any noise. I can't tell if it's the head or the cabinet causing the issue. Any ideas? I really need this cabinet and head to work but I can't figure out what could be the problem. Thanks!
Are you any good with electronics?  As in, can you work on it without killing yourself?  Lethal electricity in there.  

Take it to a tech.  If it is an older bassman from the 60's it could probably use a cap job and general check-up and clean up.  
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I know a good bit about electronics but I can't figure out what might be causing it not to output to the cabinet. It was given to me for free, and since it's a 200 Watt tube amp head with a huge cabinet, I am extremely lucky because they are expensive, but I don't have money to go to a tech lmao
Seems your between a rock and a hard spot, as there is no one size fits all fixes here, you can either diagnose and repair the problem or you cant,  And yes there are some capacitors in that puppy that can end you in a heartbeat if not discharged correctly before fooling around in there willy nilly.  Meaning just because its not plugged in doesn't mean it cant still kill you,  There are several online tutorials on tube amp trouble shooting you can try but your better off leaving it to a pro with an amp of that caliber. If not absolutely sure or capable of the repair you could end up costing yourself more in the long run, Or your family when they have to bury you,   Personally if someone were to give me an amp like that not working, and I can do some rudimentary repairs, I'd send it straight to my amp guru, Might cost a few hundred to repair and mod to better than new, but a bargain in the end, short of a blown power transformer of course, then its a break even deal, as that can be a bit spendy,  Which come to think of it may be why someone gave it to you, 
Could you possibly link me to the videos that could help me troubleshoot the amp? I want to at least try to fix it myself before I result to paying a specialist to do so
Any chance you have access to other cabs/heads? You could use them to figure out which one is the problem.

I'm guessing the head is the problem. Could be something simple, could be expensive. I'd bring it to a tech to find out.
Originally posted by primusfan
When you crank up the gain to 10 and switch to the lead channel, it actually sounds like you are unjustifiably bombing an innocent foreign land.

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Disconnect the speaker and with the amp powered down, measure the resistance across the output of the amp. Lets check the biggest possible problem first - the output transformer.
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