advice needed, Monitor Audio RXW-12 Subwoofer power supply

Switched supply for Subamplifier

Hi.

I got this subwoofer with defective switch mode power and wonder if anyone
could tell me what voltages it delivered?
I see mentioned +-40VDc but there is more connections coming from this power supply so i believe there should be several more Voltages, someone who got this amplifier and maybe could measure them all?

Thanks,
ManUtd.
 
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Picture mentioned above

Picture
 

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Do you have any idea what's wrong with it? Did you try to measure voltages? It may be that the main is down and rest are discrete, more likely they are step downs from main.

Have you looked online for a schematic? They normally take some hunting down but tend to have things like voltage clearly labelled once you find them. Also double check on the board, it looks like there's some writing next to at least one jst connector. You may be able to trace to some components that give you clues to voltage spec.
 
Thank You for info.
I changed the four caps on right side in picture
They had Bulbs on TOP and measured badly.
After change i powered it and one Mosfet in middle
popped with smoke. So i Am thinking of replacing the
Powersupply module. Therefore i need info about voltages. There is No info on the Board itself neither
on the amplifier Board.
 
Hi There - I just joined the DIY Audio forum to post an update on the RXW12...

I recently Googled faulty RXW-12 as mine has also developed a fault on the power board of the integrated amplifier.

Just to let you know that when I stripped it down, the U6 IC on the power board had completely burned out.

I reached out to the tech team at Monitor Audio on technical@monitoraudio.group and they were incredibly helpful and sent me a full list of schematics for the PCBs. They also advised that the whole amp unit shares the same footprint with the current W12 model and can be used to replace the failed amp, meaning my 10 year old but near mint cab wouldn't go to waste.

The U6 turns out to be a LNK364PN, easily available through Element14 in Australia. Now that I have the schematics I will take a while to check all the components and have a try at repairing my amp first. Wish me luck, especially with all that black gunk on the boards! :)

Many thanks to the previous posts on the forum for inspiring me to have a go, as electronics repair is a new hobby for me.

Cheers
 
Please find attached the schematics for the boards inside a Monitor Audio RXW-12 Home Cinema Active Subwoofer. Mine has the LNK364PN completely burned out. I would welcome your suggestions on where else to check before I dive headlong into soldering in a new one just in case any other components failed first and cause the meltdown.
I had a quick look at the diodes in the area and they appear to read OK.
Thanks in advance.
 

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  • RXW-12_PREAMP_SCH.pdf
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  • RXW-12_MAIN_SCH.pdf
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  • predrive.pdf
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  • power_supply.pdf
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  • drive.pdf
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  • ac_input.pdf
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