Amplifier circuit is very suitable for use in car audio speakers that use a subwoofer, with a power output of about 60W and impedance of 4 Ohm. Supply voltage ranging from 12V to 35 volts with currents +, -, and ground. If using battery then use 12V DC to DC converter which produces 3 voltage +, -, and ground.
C4 = 10uF
C7 = 100uF