This Dayton Audio SA100 100 watt subwoofer amplifier with adjustable crossover, high and low level inputs, auto on/off and phase reversal switch is perfect for building your own powered subwoofer. This plate amp offers very stable operation, with full overload protection.
https://www.parts-express.com/dayton-audio-sa100-100w-subwoofer-plate-amplifier--300-802
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