In the Evolution One, the output impedance of the final gain stages is one hundredth that of the final gain stage in most power amplifiers. This provides extremely wide bandwidth and very high current capability. The Evolution One does not employ global negative feedback–the final gain stages use only 8 dB of local, nested negative feedback. This is one-five hundredth of the amount used in most solid-state power amplifiers. The result is an extraordinarily open, liquid, effortless sound.
The new Evolution Bias system features 12 individual bias levels for optimum performance and efficiency. Evolution Bias constantly compares the audio signal at the input stage with impedance at the output stage, and adjusts the bias current accordingly. In addition, a proprietary bias monitor continuously measures and adjusts the output stage bias, eliminating the need for future adjustment or calibration.
If the DC level at the amplifier inputs exceeds a safe level, the microprocessor control automatically switches in DC blocking capacitors to prevent damage to the input stages or the loudspeakers. The microprocessor control measures the load impedance in real time to optimize the performance of the amplifier and power supply or, in the case of a short circuit, to shut the amplifier off. It monitors the regulator output voltages, the symmetry between the two halves of the balanced output stages, and it monitors the operating temperatures of the three main heat sinks.
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