Full Range, Class A/B Topology A class A/B amplifier uses two groups of transistors and it is generally considered to be the best compromise of the two classes put together. Class ‘A’ and class ‘B’. A pure class ‘A’ amplifier typically has an enormous amount of current flowing through its output transistors with no audio signal. A pure class ‘B’ amplifier has NO current flowing through its outputs with no audio signal. This eliminates virtually all of the crossover distortion that’s possible with class ‘B’ amplifiers. A class A/B amplifier is much more efficient than a class ‘A’ but without the possible distortion of a class ‘B’. As if that wasn’t enough, with a Full Range amplifier you not only have the option to run your speakers, but also your subwoofers. By just a flip of a switch from Full to Low, the PH4.600 will change from offering a complete range of frequencies that you need to be able to listen to your 2/3/4 or 5 way speakers to the “Low” that you need for a subwoofer application. MOSFET Power Supply Metal–Oxide–Semiconductor Field-Effect Transistor is a transistor used for amplifying or switching electronic signals. In our computers, our telephones, game consoles, cars, electrical appliances, and in this case, our amplifiers. They are found in systems where information is processed or stored. A MOSFET is basically an electrical switch that allows the flow of electrical current. An electrical switch has two possible states, ON or OFF. This is where the MOSFET performs its most important role in our D Class amplifiers by allowing or preventing the flow of power and creating an efficient amplifier. General Features Bridgeable outputsTri-Mode capable2 Ohm stable stereo operation with output power increaseThermal and speaker short protectionSoft Turn-On CircuitRemote turn-on/turn-off circuitBlack anodized heatsink View larger 4/3/2 Channel This feature comes in handy for a few different installation applications and is very multi versatile.The “4” channel means that you are able to simply use the PH4.600 as a 4 channel amplifier by hooking up 4 speakers to it. Fronts and rears. The “3” channel lets you hook up 2 speakers to channels 1+2 and use the remaining 3+4 channels for 1 subwoofer in bridged mode. Lastly, the functionality of the “2” channel. Channels 1+2 can be bridged to accommodate one speaker OR one subwoofer. Channels 3+4 can be used in the exact same above application. View larger Variable Bass Boost You have Bass Boost and Variable Bass Boost. The difference between the two is that with Bass Boost you either have extra bass or you don’t. But with Variable Bass Boost you have the control of exactly how much bass you want to pump out to your subwoofer(s). This is what you get with the PH4.600 Amplifier — Variable Bass Boost. View larger Low and High Level Inputs The Phantom series amplifiers have two different ways that you can get a signal into it. One is called low level input and the other is called high level input. A low level input is measured in voltages. It comes in the form of RCA outputs from the back of your receiver and goes to the RCA inputs on your amplifier. A high level input is measure in wattages. It comes in the form one positive and one negative wire from the back of your receiver to and goes to the input terminal of your amplifier in the same wire form. Low-level (RCA) input wiring is preferred for best audio performance. Always use a high-quality RCA cable for best audio performance. NOTE: Do not connect BOTH the high level and low level inputs from your receiver to your amplifier at the same time. View larger Variable Crossover Speakers reproduce sound based on high, low or mid-range frequencies. This process is called the crossover effect and occurs because the vast majority of audio systems cannot cover the entire spectrum sufficiently to minimize sound distortion and maintain an appropriate frequency ratio.In the case of our PH4.600 amplifier, a variable crossover is offered so that you, the listener, can have the ability to set the frequency at which the crossover occurs, thereby setting specific sound specifications such as the bass, mid-range and high frequency reproduction. View larger Gold-Plated RCA Low Level and High Level Inputs View larger LED Power and Protection Indicators