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Fishman LoudMini Charge smoked

Started by sratell, November 22, 2024, 08:08:29 PM

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sratell

Plugged wrong power source into my Fishman amp. Quilter 24v instead of original 12v. Now I have flashing lights - thats all! Does anyone have experience with one of these amps? Fishman ignores my calls and emails. My tube tech wont touch it. Great amp, would love to resurrect it. Any help appreciated. Thanks.

Loudthud

#1
You can't really expect anyone to reply without knowing exactly what model amp you have. A quick ooogle search shows at-least a dozen models. With only a 12V supply, my guess is it's probably a Class D design. If Fishman won't fix it, trash it and buy another.

Edit Oooge shows no "Loudmini". There is a Loudbox mini, but it has an IEC connector for a line cord. No input for a 12V supply

Edit 2 Ok, found it. Its a Loudbox-Mini-Charge. Uses a 12V 5A power supply. Same advise applies. If Fishman won't fix it, trash it and buy another.

g1

Fishman offers circuit boards at a very reasonable cost, cheaper than you can repair them.  If you are not doing SMT level repairs, you would not be able to work on the board anyway. 
You just have to figure out which board you need.
I'm not sure why they are not responding to you, I would try calling the phone number on the support page of their website.

sratell

Thank you for your responses. I was mainly trying to find out Fishmans integrity from other experiences. My amp guys negative response, the unreturned phone calls and emails with Fishman and the fact I was not finding schematics gave me the impression I was going to find a dead end no matter what. I called the support number on their website to no avail.

For what its worth it is Fishman Loudbox Mini Charge - model #494-000-582.

Thank you sincerely for your responses. I will probably buy a new one with Black Friday sales and maybe this one can be resurrected in the future...

J M Fahey

Just grasping at straws, but since you already decided to replace it anyway:

Very interesting design, main point is that you do NOT get 60W from a meager 12V supply, so I am quite certain that it is somewhat more complex than you think.

Instead of a 12V car radio type chipamp, bridged Class AB or D which can put out 14-18W tops, this one must include an internal step up converter, from 12V to something more substantial, at least +24V (suitable for a TPA3118 putting out 60W into 4 ohms).

Charger feeds an old school Lead acid 12V (7A?) "alarm/bike" Battery, which typically are well fused, because a short can make amp catch fire or explode.

So I *pray* some internal fuses blew and are replaceable.
*Only* "repair" which can be tried without schematic and SMT parts experience (and tools).

So I would open it and take some closeup pictures, showing power supply area and power amp, we might find a couple fuse holders there.

Mindou, there are also


Loudthud

There are surface mount fuses that look like a small dowel slightly smaller than the body of a 1N4007 diode with the leads cut off. Easy to remove if you have two soldering irons. Next, clean off the pads with solder wick. Add a small lump of solder to one pad. You'll need tweezers to hold the part, melt the solder on one end and position the part in place. Solder the other end, add solder to the first end if needed and you are done. I recommend you clean up any flux with flux-cleaner or isopropyl alcohol.

J M Fahey

True.

I have also seen (and replaced) some like these



which are still recognizable as fuses, but there are sneakier ones



or worse: