Subwoofer Amplifier Repair Help!?

[Rewiu]

Can you tell me if it can be repaired and if so, what parts do I need? And for the context, my subwoofer started making a loud noise when is on. I opened it to look at the amplifier and noticed that there was a melted brown substance that I removed, you can still see the traces where it was. And now I see that some parts at the base are melted!? What can I do?

 

[Nigel Goodwin]

The brown substance looks more like over-heated glue than anything else, was it hard? - if so, it's supposed to be there, and it commonly turns brown due to age and heat exposure.

If it was liquid, then it might have been leakage from one of the capacitors? - but from the picture my first impression is just glue.

 

[Diver300]

My suggestion would be to change the capacitors. The voltage and capacitance of the capacitors will is written on them. You can use higher voltage and / or larger capacitance. Make sure you match the polarity.

The diodes are probably OK. If you have a multimeter you can test them, as they should conduct one way and not the other, but you will need to unsolder one end before testing them.

 

[Tony Stewart]

If the loud noise was 100 Hz hum, then the bulk capacitors have deteriorated. Get same or equivalent high RMS rated cap. I agree, change all caps. e.g. https://www.digikey.ca/en/products/detail/rubycon/35ZLH1000MEFCG412-5X20/3568159 lowest ESR for this price