Every audio amplifier is made basically of three blocks, each one with different purposes:
- Voltage Amplifier – it receives the input signal with high impedance (tipically 47kohm) and amplifies it so that can drive the driver stage
- Driver Stage – is places between Voltage Amplifier and Output Stage and adapt and sometime “processes” the signal so that can drive the output stage
- Output Stage – is the final block in charge of deliver high currents, so that the amplifier can handle low-resistance loads such as a speaker
The project that I’m about to present is an output power stage, capable to handle more than 500w if mounted on a suitable heatsink.