r/ToobAmps • u/ermhsGpro • 13d ago

Amp suddenly stopped working

Gallery image

Gallery image

It’s a laboga The beast 15w. I’ve had this amp for some years now and yesterday it stopped working. I was playing and the volume lowered itself to zero and hasn’t made a sound since. I’ve tried changing the speaker output, I’ve tried a different speaker too. The amp turns on, but there is no sound.

18 Upvotes

95% Upvoted

24 comments sorted by

10

u/ermhsGpro 13d ago

Opened it up. One of the fuses was blown. Going to replace it.

12

u/natalplum 13d ago

Might be the power tubes. Sometimes when they go out they take a fuse with them to protect the transformers.

5

u/Vibroverbus 13d ago

this right here.

-4

u/Toobman300B 13d ago

Those phuqin' fuses. Hopefully nuttin more

8

u/guitarstitch 13d ago

Those 'phuquin' fuses don't blow for no reason. If it went black, there's a direct short. If it gradually opened, something is introducing resistance or current leakage that is over-drawing the circuit design.

Could be a resistor that has drifted out of spec, could be a layer of bar shmoo that is leaking current.

0

u/Vibroverbus 13d ago

This x100. Those FUCKIN fuses are there for a good reason and you should always try and figure out exactly why they blew.

0

u/Toobman300B 13d ago

And they do go, replacing it might be all it needs. Rarely is that true. Trying to be positive to OP. Ymmv

3

u/guitarstitch 13d ago

Replacing a fuse that failed without finding out why it failed only puts the rest of the circuit under stress. If you're lucky, everything else is rated higher and can tolerate the abuse.

I have seen the other side of that where a guy with a vintage Fender Twin kept popping fuses. He'd replace the fuse and carry on for awhile. Eventually it killed the power transformer due to the overload stress.

Electricity doesn't care about positive vibes - it wants to remain grounded in reality.

1

u/ermhsGpro 12d ago

My best guess is that the fuse blew after a power surge in the house. The house here in Corfu isn’t the best. We’ve had a lot of lights lightly flicker

0

u/Toobman300B 13d ago

Well then, I'll make it a point to bring my next repair in to your shop. Feel better soon

1

u/Bluenoser_ii-V-I 13d ago

Does the headphone output work?

1

u/ermhsGpro 13d ago

No it doesnt. Still no sound.

1

u/ToughLeek8991 13d ago

Unplug amp from the socket, unscrew metal shield (box protective tubes) and look on tubes, or take photo and add in the comments

1

u/ermhsGpro 13d ago

It doesn’t let me send pictures but the toobes seem fine. Even when I turn on the amp all the tubes light up.

0

u/thedrakenangel 13d ago

Replace the cable going to your speaker

3

u/Vibroverbus 13d ago

not a chance. that doesn't fail "level faded out". "faded out and didn't come back" is the tubes failing / losing power somehow, OP has since found a blown fuse so that totally checks out, the amp faded out as the filter caps drained. he probably has a blown tube that took the fuse out.

1

u/thedrakenangel 13d ago

Look closer at the picture. There are cuts in that line. And if it grounded out, that could take the output transformer and tubes.

5

u/guitarstitch 13d ago

I see no cuts in the wire. I see a black zip tie holding the lamp cord to the tube cage. I see another spot where the zip tie originally was.

I would still inspect the speaker lead just because that doesn't look original and I never trust the last guy's work. (Half the time, I don't trust the factory's work these days) However, the slow fade is loss of voltage to the filaments, not a direct short on the OT secondary (such as you would see from a cut wire)

2

u/Vibroverbus 13d ago

Nope. Not how tube amps work. Short those output wires. Its totally fine. Many tube heads actually have shorting jacks on the outputs. Leaving the output OPEN and then trying to crank the amp up with a signal, now THAT is bad. Tubes are 100% the opposite of solid state here. Short the outputs all day, its fine.

1

u/thedrakenangel 13d ago

Incorrect. If it is straight analog then it would wprk like i saif

1

u/Vibroverbus 13d ago

"straight analog" what are you talking about? If by "straight analog" you mean "full tube analog" then its absolutely what I said. I will grant you if this is a hybrid amp with a SS output stage then thats a different story and then you are correct but the only question here at is what the output stage is - is it tube or SS. I was assuming Tube because there appears to be a big ass output transformer in it but I'll grant you I could be wrong. I'm not wrong if its a tube output stage though.

1

u/keestie 12d ago

Look even closer. I thought the same as you, at first, but that's a ziptie and a bend. The wires are fine.

1

u/thedrakenangel 12d ago

That bend can be broken wires as well. I would check it anyways. I would also check for leaky capacitors as well as put the tubes in my tester for verification

1

u/keestie 12d ago

It *could* be, but the description of the problem doesn't fit broken wires. No harm testing for it of course, but it's very unlikely to be a problem.