Simple Power Amplifier 60W

With the TR1 we set the DC voltage output from the amplifier at low levels [20 to 50mV is] a good level. Good thing they are the two transistors Q1-2 of the differential amplifier, they have the appropriate characteristics. With TR2 trimmer we set the bias current transistor power output stage, around 50mA for each sector. This regulation is to be without any input signal, the digital multimeter at the terminal since the resistors R22-23-24-25 and set himself TR2 should we know, about 25mV DC, which is appropriate in the current 50mA

Part List :
R1=1.5Kohm R21=10ohm 1W D1=5V6 0.4W zener
R2-9=10Kohm R22-23-24-25=0.47ohm 5W Q1-2-3=BC557
R3=2.7Kohm TR1=100ohm trimmer Q4-8=BD140
R4=5.6Kohm TR2=470ohm trimmer Q5-7=BD139
R5=3.3Kohm C1=2.2uF 100V MKT Q6=BC549
R6-12=470ohm C2=330pF Q9-10=TIP2955 [MJE2955]
R7-11=1.2Kohm C3=100uF 16V Q11-12=TIP3055 [MJ3055]
R8=560ohm C4=100pF
R10=220ohm C5=27pF F1-2= 3A slow Fuse 5X20mm
R13-14=47ohm C6=3.3nF 100V MKT
R15-16=33ohm 1W C7-8-9-10-13-14=100nF 100V MKT All resistors is 1/2W 1% metal film except for announce differently
R17-18-19-20=220ohm 1W C11-12=220uF 63V