Load impedance compensation circuit in audio power amplifier

Shown is a load impedance
compensation circuit commonly used in power amplifiers . In the circuit, Ri and cI are "Joubert" nets, and
R2 and Li are also compensation networks .
    This compensation network consists of two parts: one is Rl and CI.
This network can compensate for the inductive impedance of the speaker so that the total load
impedance of the amplifier does not increase significantly in the high frequency band. In addition, the network has an attenuating effect on ultra-high frequency signals, causing the gain of the amplifier to decrease
in the high frequency band outside the passband .
Helps suppress high-frequency self-excitation. The second is L-
and Rz. The combination of these two components is used to eliminate
the unstable effects of the amplifier's high-frequency band caused by the speaker's distributed capacitance.