Sure Electronics 2 X 25W 6 Ohm Class D Audio Amplifier Board - TDA7492 A perfect "Class D" architecture Gain adjustablefour fixed gain settings: 25.6 dB, 31.6 dB, 35.1 dB and 37.6 dB Line level audio signal input Excellent heat sink eliminates your worry on heat dissipation Click & Pop Noise Reduction