Abstract: A switching amplifier drives balanced piezoelectric or other capacitive or reactive loads with a minimum physical electronics volume, enabling a compact arrangement that can combine amplifier and transducer at the same physical location. Power supply current is minimized by using two or more transducers driven with phase-shifted signals, resulting in stored energy being cycled between the transducers rather than being carried over the power supply lines for storage in a power supply. Auxiliary power supply capacitors to store energy coming out of the load can thus be minimized. The modulation scheme puts the switching frequencies in common-mode while the baseband signals are differential mode. The common-mode switching frequency signals are blocked from the loads by a common-mode inductor. The common-mode inductor can be physically small as a result of the large baseband load currents being in differential mode.