A Class-D amplifier system may include an input stage that includes an N.sup.th order filter, where N>1. The input stage filters an input signal to provide a filtered output signal, an input of the input stage being configured to receive the input signal as a digital pulse-width-modulated (PWM) signal. A comparator provides a quantized output signal based on the filtered output signal. An output stage is connected between a first voltage rail and a second voltage rail. The output stage provides a switching output signal at an output that varies between the first voltage rail and the second voltage rail based on the quantized output signal. A feedback path connects the output of the output stage with the input of the input stage, such that the N.sup.th order filter compensates for variations in at least one of the first voltage rail and the second voltage rail.

 
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