MOSFET amplifier with MOSFET for your build in electronic hobby.
I would like to show you here a basic MOSFET amplifier or power Amp which Output power is plus/minus 100 Watt/RMS with
8 Ohms or ohter plus/minus 160 Watts /RMS with 4 ohms.
Regarding this circuit simplicity, The distortion is plus/minus 0.1 %.
For band-width -3 db(decibel) is gain for 4 Hz to 96 Khz, it is limited by C1, R1, C2 and R2.
In the two transistors are T1 and T2 makes a first differential stage part, So,current source(I) of +/- one mA is set with resistor R3.


For the upgraded project, The current source(I) is more efficient in stability. Coil P1 allows a fine tuning of direct current voltage at amplifier’s output. Place the Coil P1 with it’s half value for first power up, then turn it slowly for a lowest DC output voltage. Use a first quality compoment.

Electronic Part

C1 = 2,2 µF MKP, MKT 100 V
C2 = 330 pF céramique 50 V
C3 = 100 nF MKP, MKT 100 V
C4 = 100 µF 40 V électro-chimique
C5, C6 = 18 pF céramique 50 V
C7 = 100 nF MKP, MKT 250 V (C8 = 47 µF 100 V)
R1, R3 = 47 K (R3 = 330 -> 470 Ohms)
R2 = 2K2
R4, R5 = 3K9
R6 = 1 K
R7 = 27 K
R8, R9, R11 = 100 ohms
R10 = 10 K
R12, R13 = 470 ohms
R14, R15 = 0.33 ohms 5 watts
R16 = 10 ohms 3 watts (R17 = 1 K R18, R19 = 10K)
T1, T2, T9,T10 = 2SD756A,2SD716A, BC556B (attention au brochage différent – take care for pin layout)
T7 = IRFP240, 2SK1530, 2SJ162, BUZ900DP, BUZ901DP (attention au brochage different – take care for pin layout : GDS GSD)P1 = 100 ohms (25 tours – 25 turns)

Source: http://www.free-circuit.com/power-amplifier-mosfet-100w-with-irfp240/