Choose the number of channels based on how many independent speaker zones or audio feeds you need, with ENERGY STAR amplifier options supporting one, two, or more channels for low-impedance and high-impedance systems. Select output power based on the connected speaker load and desired headroom, using per-channel ratings for 4- or 8-ohm systems and bridgeable or 70V and 100V modes when a higher-power mono output is needed.

Low-impedance ENERGY STAR amplifiers drive speakers rated at lower impedances, commonly four or eight ohms, and are suited to shorter speaker runs or higher-power direct connections. High-impedance ENERGY STAR amplifiers support distributed audio systems using 70-volt or 100-volt lines, which can simplify connections to multiple speakers over longer cable runs.

Consider whether the amplifier must fit a rack, table, wall, or plenum space, and confirm its enclosure size, cooling method, and support for low-impedance or 70V and 100V high-impedance systems. Match the amplifier’s channel count and wattage to the loudspeaker load, then verify the available AC supply and whether features such as bridgeable outputs or selectable stereo and mono operation support the system design.

ENERGY STAR amplifiers support efficient operation in distributed audio systems through energy-conscious designs, including Class D amplification, convection or fanless cooling, and standby modes that reduce power use when the system is not active. Depending on the model, selectable low- and high-impedance outputs support distributed speakers on 70V or 100V lines, along with stereo or multi-zone configurations.