Abstract: A charge amplifier includes an operational amplifier having first and second voltage dividers across its output connected to a capacitor and a resistor, respectively, in an R-C network returned to one input for magnifying the apparent value of the impedance of the capacitor and of the resistance of the resistor. Its output is also connected to an integrating network including another operational amplifier having its output supplied to a third voltage divider supplying signal to another input of the first operational amplifier. A pair of differentially coupled piezoelectric charge sources supply signal to the amplifier through filters and the second voltage divider has a portion shunted by a parallel connection of back-to-back diodes and another resistor for effectively attenuating response to low frequency signals.