500 Watt Audio Power Amplifier What can be done to increase available audio power amplifier? The answer is either decrease load impedance or increase supply voltage. The lower the impedance, the more current is needed, making the construction of low impedance output stages more difficult (there are some other practical limits), so let's increase supply voltage! Components/parts list : R1,R11 47K R2,R3 33K R4 1K5 R5,R7 2K2 R6,R8 100R R9,R10 56R R12 820R R13 10R/5W C1 220nF C2,C3,C4 100uF/100V C5,C6 100pF C7 100nF/100V D1,D2 IN4002 TR1,TR2 D438 TR3,TR4 B560 TR5,TR8 A958 TR6,TR7 C2168 TR9,TR10 C2922 TR11,TR12 A1216