A closed loop amplifier system comprising a modulator that provides a pulse-width modulated (PWM) output signal based on an input signal, the modulator having a variable closed loop transfer function. The system also comprises a ramp generator that provides a ramp signal to the modulator, the variable closed loop transfer function of the modulator varying as a function of the ramp signal. The system further comprises a controller that controls the ramp generator to provide the ramp signal to adjust the variable closed loop transfer function during transitions between operating states of the amplifier system.