When you use 4 ohm speaker then you get 14 Watt output power, and around 8 Watt if you use 8 ohm loudspeaker. Make sure the 100n and 100u capacitor is wired as close as possible to the power input pin of the TDA 2030. You might wonder why we use 100uF and 100nf in parallel, if you think that we need 100.1uF capacitor then you’re wrong. All we need is just a capacitor around 100uF with small equivalent series inductance. At low frequency, the “relatively high” series inductance of the 100uF electrolytic capacitor can be neglected, but not for the high frequency. At high frequency, the TDA2030 is protected from instability by the 100nF capacitor, because the signals find the low inductance path here to bypass the fast power source variation.
