Here the TDA2050 amplifier with current environmental protection. In this scheme, there is a current environmental protection: the signal from the output passes through the connecting cables and chains of the column (in this case takes into account the reactance of the circuit section of the 4th pin of the chip to R3), then the signal is removed from the NFB by R2 R3 and fed to the inverted input circuits .
Parts list : R1, R2 : 22KΩ R3 : 2,2Ω C1 : 1uF/25V C2, C4 : 220uF/50V C3 : 100nF DA1 : TDA 2050
