An amplifier circuit has a transducer biasing node for outputting a transducer bias voltage for biasing the capacitive transducer and a signal node for receiving the input signal. An amplifier arrangement comprising a feedback resistor network provides an amplified output signal. A voltage buffer provides a buffered bias voltage at a buffer node which is connected to a terminal of the feedback resistor network, to at least partly define the quiescent level of the output signal. The buffer node is electrically coupled to the transducer biasing node via a capacitance which may form part of a bias filter.