MR1200PA 4-Channel 1200W Full Range Class A/B AmplifierFeatures:Weather Proof 1200 W MAX Power 4 Channel225 W X 4 RMS @ 2 ohm113 W X 4 RMS @ 4 ohm450 W X 2 RMS Bridged @ 4 ohmFull Range, Class A/B, MOSFET Power SupplyHigh and Low Level InputsFixed High Pass Crossover, Variable Low Pass Crossover, Variable Bass BoostInclude Remote Subwoofer Control2 Ohm StableThe lowest impedance accepted by this amplifier is 2 ohms. Amplifiers that are 2 ohms stable produce more power resulting in more volume. This amp can comfortably power speakers or subwoofers with all channel(s) being used at a load of 2 ohms.BridgeableBridging an amplifier means to combine channels of a multi-channel amplifier to get more power or flexibility out of it. For instance, on a 4 channel amp, channels 1 and 2 could be used normally for your speakers, and channels 3 and 4 can be bridged for more power to a single subwoofer. A 2 channel amp can also be bridged to power a single subwoofer.Class A/BClass A/B amplifiers have long been known for their ability to produce great quality sound while performing more efficiently than pure Class A amplifiers. We have developed a specific linear circuitry that further reduces distortion while increasing both sound quality and power output.Fixed High Pass FilterFixed High-pass filter gives you the ability to filter the frequencies that pass through to the full range speakers from a fixed frequency point.Fully MarinizedFully Marinized is the term we use for our Marine and Outdoor products that are Weather Proof. We integrate high-tech, state-of-the-art waterproofing materials plus special UV coatings for plastic surfaces, coated circuit boards and connections to protect the product against the harsh outdoor elements and resist corrosion.High and Low Level InputsAn amplifier with both high-level and low-level inputs provides flexibility by allowing you to build an audio system using virtually any standard factory or aftermarket source unit. High-level (speaker level) inputs accept the signal from the speakers, while low-level (RCA) inputs accept the signal from the pre-amp outputs of the source unit.MOSFETMOSFET stands for Metal Oxide Semiconductor Field-Effect Transistor. MOSFETs are used either as a switch or to amplify a signal. MOSFETs are superior to other FETs, because they require less current to operate, which makes them better suited for car audio.ProtectionIf the amplifier gets too hot, the thermal protection circuit turns the amp off and allows the amp to cool down before turning it back on. If a speaker fails causing an electrical short, the protection circuit will automatically cut the output and remain in that state until the short is resolved. These safety features give you peace of mind knowing the amplifier is constantly monitoring conditions to protect itself.Subwoofer Level ControlThe ability to boost or attenuate the sub level when an amp and subwoofer are connected to the subwoofer pre-amp output.Switchable Input SensitivitySwitchable Input Sensitivity gives you the freedom to connect the amp to any standard source unit and have peace of mind it will be within range to properly match the output of the source unit allowing you to use the volume controls on your source unit the way it was designed.Variable Bass BoostVariable Bass Boost allows you to adjust the low bass within the boost range to just the way you like it.Variable Gain ControlVariable Gain Control lets you balance the amps output with the speakers or subs the amp is driving. To much gain will lead to distortion and to little will lead to clipping.Variable Low Pass FilterVariable low-pass filter gives you control over the frequencies that pass through to the subwoofer.WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.