50 watt Mosfet amplifier Circuit

50 watt mosfet amplifier circuitThis 50 watt Mosfet amplifier Circuit comprises a differential amplifier composed by Q1 and Q2. Serves as a decoupling capacitor C8 so that the DC voltage is not exceeded. While C1 and R1 will remove unwanted high frequencies.

Transistors Q3 and Q4 will serve as a driver to be sufficient to drive the amplifier level by the end MOSFET IRF9530 and IRF530. this mosfet amplifier output inductor L1 will pass before to the loudspeaker. While the C5 and R15 will reduce the noise that does not come out through the loudspeaker.

In order to obtain optimal results, it is recommended to use a power supply with a minimum flow of 10A with a voltage of 35V symmetrical.

50 watt Mosfet amplifier Circuit Parts list :

R1, R12 : 4.7K
R2 : 47K
R3 : 15 K
R4 : 1.2K
R5 : 47K
R6 : 1K var
R7 : 820 ohm
R8 : 10K
R9 : 680 ohm
R10, R11 : 2.7K
R13 : 560 ohm
R14 : 2.2K
R15 : 10 ohm 2W
C1 : 220pF
C2, C3 : 47uF
C4, C6, C7 : 100uF
C5 : 68nF
D1 : 1N4002
Q1, Q2 : BC556
Q3, Q4 : BC546
Q5 : IRF530
Q6 : IRF9530
K1 : 8 ohm


  • Assemble the circuit on a good quality PCB.
  • Use the + / -35V DC dual power supply to power the circuit.
  • To make the L1 12turns enamelled copper wire on a diameter of 1 cm
  • C6 and C7 should be 50V; other electrolytes can be 10 or 15V.
  • The heat sink is required for the MOSFET. A 8x4x4 inch finned heatsink.