Abstract: Various examples of systems for powering a linear motor with a multi-phase amplifier are described herein. In some embodiments, an apparatus includes a plurality of current sources for supplying power to an electronic device. The plurality of current sources are configured to supply a substantially constant direct current to a load, and each of the plurality of current sources is configured to supply a periodic alternating current that is out of phase relative to the periodic alternating current of one or more of the other current sources. A sum of the periodic alternating currents from the plurality of current sources is configured to provide the substantially constant direct current. Embodiments of the systems can be used in vibration testing equipment such as electro-dynamic shakers.