Background: A power supply must be large enough to handle the maximum voltage and current necessary for the amplifier to drive its maximum rated power into a specified load. In the process of achieving this requirement conventional power supply designs produce large quantities of heat, are heavy, and take up precious real estate. It's no secret that heat is a power amplifier's greatest destructive factor. The larger the power supply, the more heat the output stage will be required to dissipate. An articulated power supply, like VZ, can bypass much of this dilemma by reducing the voltage applied to the transistors when less voltage is required. Reducing the voltage decreases the heat. Subsequently the amplifier runs cooler allowing more power to be safely packed into the chassis. The VZ supply is divided into segments to better match the voltage and current demands of the power output stage. Bear in mind that audio signals are complex waveforms. The average level of music is always much less than the peak level. This means a power supply does not need to provide full voltage all of the time. The VZ supply is divided into two parts. When the voltage demands are not high, it operates in a parallel mode to supply less voltage and more current. The power transistors stay cooler because they are not forced to needlessly dissipate heat. This is the normal operating mode of the VZ power supply. When the voltage requirements are high VZ switches to a series mode to produce higher voltage and less current. The amplified output signal never misses a beat and gets full voltage only when it requires it. Sensing circuitry observes the voltage of the signal to determine when to switch VZ modes. The switching circuitry is designed to prevent audible switching distortion to yield the highest dynamic transfer function-the customer hears only the music and not the amplifier. You get not only the maximum power with the maximum safety; you also get the best power matching to your load.