I need a schematic for a KEF 25B subwoofer plate amplifier model SP2298.
Or a replacement plate amp cheap.
Or a replacement plate amp cheap.
This is about 100 watts, mono (transformer couldn't do more than that). Looks like 4 large tab/screw output devices, and 1 small device thermally coupled to the heat sink. There's a lot of heat discoloration around the crappy little power supply diodes, but that could be symptom rather than cause (or neither).
Maybe I'll just close up the hole with a plate and make it passive, but I have no mixer or mono amp nor small bridgeable amp, and the voicecoil is not a dual coil.
The surround is intact, but it feels like the type of foam that gets a bit sticky before it crumbles completely. Stamped frame. I'm not impressed.
I guess what I have is one bass-reflex box for a 10". Just what I never wanted. And I paid $50 for it. There's another on eBay with the exact same problem (blows fuse), but then shipping makes it unreasonable. Unless repairing the pair on amps would become cost-effective.
The surround is intact, but it feels like the type of foam that gets a bit sticky before it crumbles completely. Stamped frame. I'm not impressed.
I guess what I have is one bass-reflex box for a 10". Just what I never wanted. And I paid $50 for it. There's another on eBay with the exact same problem (blows fuse), but then shipping makes it unreasonable. Unless repairing the pair on amps would become cost-effective.
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Getting desperate. I no longer have the equipment to do this myself, but I suspect I could replace the powersupply rectifier diodes and all the output tansistors for much less than getting a new plate amp.
Can you post the static ohms of your driver. Mine must be shorted because it checks at .2 ohms. I have not been able to locate any source of a schematic. Mine is blowing the AC use. Mine also has the discoloration on the board at the diodes.
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