This is the circuit of 30W stereo amplifier. It is small and compact stereo amplifier is powerful but can easily be used to replace your broken amplifier or new construction, or to make an active speaker.
Using only active component (the right and left channel and IC1 TDA1521 monolithic integrated circuit, which contains a double line-end audio amplifier completely is integrated each capable of providing from 10 to 12W to the load 8ohm or 15W into 4ohms (30W music). Voltage gains of the amplifier is fixed at 30 db.
Power supply: 12 V symmetrical dual voltage
Maximum Power Output RMS: 2 x 15W / 4 ohms
Maximum power output music: 2 x 30 W / 4 ohms
Input sensitivity: 300 mV / 20 kilo ohm
Frequency: 7 Hz to 60 kHz (-3 dB)
70 dB for each channel
Output power (R = 8 ohms): 2 x 10 W RMS
Output power (R = 4 ohms): 2 x 15 W RMS
Bandwidth (-3 dB): 7 to 60 000 Hz
Sensitivity to maximum power (8 ohms): 290 mV rms.
Sensitivity to maximum power (4 ohms): 250 mV rms.
Input impedance: 20 kilo-ohms
High quality stereo amplifier
Protection against overload
R1 = 8.2 Ω 1/4 W
R2 = 8.2 Ω 1/4 W
C1 = 22nf ceramic
C2 = 22nf ceramic
C3 = 100nf multilayer
C4 = 1uf 63 V Polyester
C5 = 1uf 63 V Polyester
C6 = 4700uf 25 V electrolytic
C7 = 4700uf 25 V electrolytic
D1 = 1N5404
D2 = 1N5404
D3 = 1N5404
D4 = 1N5404
IC1 = TDA1521
Note- For IC’s protection used a Heat Sink. To reduce its heating effect.