12-volt audio amplifier manufacture

According to the manufacturer, the TDA2002 is 8W and the TDA2003 is 10W.
The connections, the values ​​of the components and voltage are the same.
For test instruments they can work with 9 Volts, as power amplifiers work perfect with 14 volts, and it is better not to reach 18V.
Parts List:
Pot1 is a logarithmic potentiometer from 10K to 50K.
C1 if not for "Woofer" can be 1 or 2.2 microfarads of 10 volts and up.
If you want better bass it can be 10 microfarads.

Cf can be 470 picofarads, if there is noise it can be of higher value
trying not to sacrifice high notes (treble or treble)

R1 is 1000 ohms, can be small (less than 1 / 8W)
R2 is 3.3 ohms (less than 10 ohms *, greater than 2)
R3 is 390 ohms (can be: R2 x 100)
If we want more profit we increase the value of R3.

C3 1000 microfarad 16 volts (in 10 volts works fine)
R4 1 ohm (coffee, black, golden, golden)
C4 0.1 microfarad, in some it is represented as 104.
C5 1000 microfarad 16 Volts or greater.
If the source is well rectified and there is not much cable distance it can be