Sudden death of my old Alligator AP150W - Pics.

[The_Theramist]

So, I recently picked up an Alligator AP150W amp purely for nostalgic reasons.
It was one of the first amps I ever used in my first proper band.

Also because they are geared to work as a guitar, bass and keyboard amp which is great as I needed a bass amp too.
It has a 2x12 cab and is separate unlike most versions of this amp. According to the previous owner this one is a one off, built for a trade show. You can see clearly that the amp part would fit fine into the top part of the cab.

I was planning to slave one to the other and have a bit of a stack.
I did do this using the dual outputs on my overdrive pedal, but I now know I could use the slave out on the Alligator.


I had to replace all the pots on the front panel when i bought it as they were all shot.

So I go to fire it up yesterday and it's silent. Seems to power up but no sound coming through to the speaker.
Time to get out the soldering iron and check all the joints and for anything obvious.
Then I notice something odd I've not noticed before.


The two holes where the heatsink should be are not used and they are somewhere else.

I open and something seems odd:


The actual amp board has been replaced:


Something about the board looks familiar so I google it.
It's been replaced with a Maplin standard kit amplifier.

I also notice one of the main capacitors is swollen:


The transformer:



So where do you think I should start?
Replace the capacitors, the transformer or just dump it and keep the cab?

I've tested all the output fuses and they seem to be fine. I've not even moved it since I last used it.

Any suggestions?

!m!

[Tortuga]

Is it really worth any trouble? There's a hell of a lot of good amps that can be had for less than the time, effort, and $$$ it'll cost to salvage what may not be a very good amp. If someone already replaced that power section it's probably not gonna sound like what it did before. And, considering it's probably had a transistor (or two) suicide, it's telling you that it's time to buy a Katana.

[The_Theramist]

Yep. That's what I've been thinking.

Last night, just to add to my equipment failures, my Line 6 floorboard failed to work at all while I was at the local jam night.
Time to say bye-bye to that as well I think.

Good call on the Boss Katana's, but I've been looking at the Bugera 333 2x12 combo's. They look like a lot of amp for the money.

!m!

[Devin]

I'm surprised to see a redface Line 6 Spider amp that still (presumably) works. I bought the 2x12 version of that amp when it was first released and I dont think it even made it 5 years for me

[itchyfingers]

Yep. That's what I've been thinking.

Last night, just to add to my equipment failures, my Line 6 floorboard failed to work at all while I was at the local jam night.
Time to say bye-bye to that as well I think.

Good call on the Boss Katana's, but I've been looking at the Bugera 333 2x12 combo's. They look like a lot of amp for the money.

!m!

Public service warning - careful of those Bugera's, they could burn your house down.

Also, you get SO much amp for the money with the Katana. This is a pic of my rig from my gig on Saturday...

Amp: $260 used
Cab: $125
Speaker: $40
Tuner & Bion Boost: $120
Pittman Strat: Priceless.

[clipless bumper]

.....
Pittman Strat: Priceless...

Yeah - I've never been able to figure out what one of them costs.......

[mgraves]

spend a few minutes to build an audio probe and start tracing the signal. i'm betting a dead mosfet (or both), but i'd trace the signal before i replaced anything. it' not a very complicated circuit, so it'd should be too much trouble to suss out.

[The_Theramist]

Thanks for the replies guys.

While on the hunt for a new amp in the local music stores, I happened across a Peavey ValveKing 2x12 for £200.
It's really nice and sounds huge. My only issue is it's a bit too loud, so volume pedal on the effect loop and it's usable at home levels.

I'm surprised to see a redface Line 6 Spider amp that still (presumably) works. I bought the 2x12 version of that amp when it was first released and I dont think it even made it 5 years for me

I am surprised too, but I've had mine for about 15 years now and it's still going strong, just not quite what I want right now. I managed to sort out the floorboard as it turned out just to be a bent pin in the socket. I keep trying to get rid of it, but I just cant bring myself to do it.
I offen lamented not getting the 2x12 but maybe I shouldn't.

spend a few minutes to build an audio probe and start tracing the signal. i'm betting a dead mosfet (or both), but i'd trace the signal before i replaced anything. it' not a very complicated circuit, so it'd should be too much trouble to suss out.

I will do that, thanks. I probably shoudl just throw it but I just cant bring myself to do it. When I have more time and motivation I'll do some investigation.


As for the ValveKing, the only main issue I've had is getting a footswitch to work properly. It seems that it is a simple latching sleeve to ring for channel and sleeve to tip for boost, but i really dont know how they get the LEDs to work. With an LED in the circuit the boost does not work but the channel select does. I purchased a cheap footswitch from Amazon witht he intent of rewiring but have only had success without the LEDs on. Just to mess with you too, the LEDs light but obviously the Relay is just a little underpowered with the resistor.
More investigation is required.

!m!