The QD-4240 is a quad, four channel power amplifier amplifiers capable of driving 4O loads. Their clean sound quality makes them ideal for permanent installation in professional PA systems or for portable use for live performances.Primarily designed for multi-zone use such as in bars and restaurants, where separate control of the music in several areas is required, these designs may be applicable for use in any situation where a number of low-power amplifiers are required, such as for cue-feeds, effects-loudspeakers, museum displays etc.Three models are available; each combines four separate low-impedance amplifiers in a single 2U rack-mounted case. Each amplifier has an individual input XLR/TRS "Combo" balanced input connector, a level-control with associated signal-present and clip LEDs, and 5 way binding-post speaker output terminals. For added versatility, an input-selector switch allows each pair of amplifiers to be driven either separately (stereo), with inputs in parallel (dual mono), or bridged into mono. Clip-limiters are supplied on each channel to help prevent distortion due to excessive signal levels.All units have soft-start protection circuitry and feature power, signal, protection, and clip indicators on the front panel. These amplifiers are fan-cooled with circuit-protection and turn-on delay. The quad series amplifiers are powered by 100-120VAC or 220-240VAC 50/ 60Hz (depending on country requirements).FeaturesFOUR CHANNEL AMPLIFIERFour channels in a single chassis.ADVANCED PROTECTION CIRCUITRYThermal overload protection, DC detection circuitry and power-on delay help protect your amplifier and system components.BRIDGED MONO OPERATIONCan operate in monaural mode for high- power and performance.SLIM DESIGN, COMPACT SIZEStreamlined design fits in a compact 2RU space.