What happened amp is quiet now

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I had a buddy jam on my tsl 122 and had it plugged into a cab with two 15s wired for 4 ohms and plugged it in left stereo on 4 ohms with the stock speakers in the right channel and it was amazing now there's no sound, power tubes or speaker output transformer?? How do I check and get it working I guess I had it running at 3.2 ohms instead of what it's rated for 2 x 8 ohm cabs..

I did the bias mod board on it and had replaced the tubes a few years ago when I got that done I love how it sounded with this bass cab that was the third time I used it with the bass cab and it died on me after a power down silent next day
 

Pete Farrington

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Were the amp’s parallel 4 or 8 ohm sockets set for 4ohms or 8ohms?
If 4, the combination of that and the combo’s 16ohm cab in the 16ohm socket would put half the intended load impedance on to the output valves.
If 8, the combination would put 1/3 of the intended load impedance on the output valves.
Neither should cause a problem, unless the amp was turned up high and the output valves were worked hard.
 
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Check the HT fuse....if your are lucky this one protected the amp on the FUBAR
BTW: there is nothing bigger SNAFU you can do then connecting two Cabs to different Output Windings
You got it the HT fuse has a break in the middle I just ordered a 5 pack of marshall 1 amp fuses last night when I saw
 
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Were the amp’s parallel 4 or 8 ohm sockets set for 4ohms or 8ohms?
If 4, the combination of that and the combo’s 16ohm cab in the 16ohm socket would put half the intended load impedance on to the output valves.
If 8, the combination would put 1/3 of the intended load impedance on the output valves.
Neither should cause a problem, unless the amp was turned up high and the output valves were worked hard.
I had the amps switch on 4 ohms and had the 4 ohm cab in the parallel jack, with the combo 16 ohm load in the other parallel jack and it sounded really good. I had it on about 6 volume and everything else dimed tone shift engaged and deep engaged showing a friend the modern tone I had and we only worked it for about an hour that night
 
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Ok, apologies, you were correct then, a 3.2ohm load on a 4ohm output, not a big deal. I assumed that the combo speaker was left in the 16ohm output.
I replaced the fuse with one from home Depot and it's working again. Should I be concerned that something inside is wrong since the fuse blew? What's a good bias for the amp so I can tell it's not going haywire
 

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