The DA Series multi-channel digital power amplifiers are ideal for multi-zone distributed speaker systems and professional sound applications. Engineered with Class D technology, the new DA Series amplifiers operate at 85 percent efficiency and consume almost one-third less power than conventional analog amplifiers. The compact and lightweight single or dual rack-space design and ultra-low heat dissipation allow designers to rack-mount up to five units without open space between units. The DA Series is comprised of high and low impedance four-channel models each equipped with an independent power supply for each channel to assure continuous operation and unmatched reliability and performance. Other features include recessed stepped attenuators for precise gain calibration, removable dust filters for easy maintenance and optional isolation transformer.