240W. The power amplifier power of Yajia am75 is 240W. The power of the power amplifier refers to the maximum output power, and the distortion is also very large. Yajia AM69 and AM75 are pure power amplifiers with decoding. Schematic diagram of preamplifier and power amplification board. , the original operational amplifier is composed of Mitsubishi 5238, C2910 and A1208 tubes K170 and J74.