Blown Bass Amp (help!!)

[j. river]

So in an unfortunate incident, two of my amps got blown up from connecting them via their speaker outputs while they were both on. My guess is that this blew the output transformer?

One of them, a Kustom 200, still turns on, however it makes a thick hummmm. The other, a Hartke 3500 300 watt bass head won't turn on at all, it blew a fuse in the process, so I changed it out, and it keeps coming on for a second then getting blown again and it turns off(it's definitely the right fuse amps/volts).

Does this mean the amp is totally crapped out, or is there another explanation for why it would blow a fuse off the bat?
I'm accepting that the Kustom is a lost cause, but my hopes are that there is a better way to solve the issue with the hartke as opposed to needing a new output transformer.

Any help would be greatly appreciated!

[Enzo]

HI
Solid state amps do not have output transformers

Transistors, yes.

The output stages of the two amps were likely damaged. I see no reason why they both would not be repairable. They blow fuses because the outputs are shorted. DC on the speaker leads can damage speakers, and will draw max current from teh amp, blowing fuses.

We start by looking for shoprted output transistors on the power amp boards, and driver transistors amd assicoated resistors, etc.

[Wonker]

HI

We start by looking for shoprted output transistors

How do you test a output transistors?

[Enzo]

You don't really have to understand how a part works to see if it is shorted inside. Power transistors either have three legs, or two legs and an electrically active case. if any two or three of those are shorted together - that means have a very low resistance - then the part is likely bad. Remove it from the circuit and test again to verify it was the part itself that was shorted, and not the circuit around it. Use your ohm meter for this. And of course the amp is not powered at the time.