On the left: Darlington pair capacitance multiplier (2pcs NPN transistor)
On the right: Sziklai (Compound) pair capacitance multiplier (1pcs NPN + 1pcs PNP)
The resistor before the capacitors emulates the ESR. On lower frequencies it is does not matter. On high frequencies makes difference.
The capacitance appearing at the base of the output device is effectively multiplied by the gain of the device.
You can adjust the voltage drop with the resistor to sink current to ground from the capacitor. You need to adjust the voltage drop to bigger than the voltage ripple.
https://sound-au.com/project15.htm
https://sound-au.com/articles/cmpd-vs-darl.htm
https://youtu.be/wopmEyZKnYo
Sziklai (Compound) Pair β = βQ1 × βQ2 + βQ1
Darlington Pair β = βQ1 × βQ2 + βQ1 + βQ2
