Accuphase E-4000 Stereo Amplifier - Class AB Amplifier The E-4000 is part of Accuphase’s 12th generation of high-powered Class-AB integrated stereo amplifiers. The E-4000 integrated amplifier has emerged from separate amplifier technologies. The preamplifier section features AAVA using ANCC to allow for volume adjustments that maintain high levels of vibrancy. The power amp section employs balanced transmission utilizing the instrumentation amplifier principle to drive noise suppression to its limit. The E-4000 is equipped with a four-fold parallel push-pull configuration of power transistors driven in Class AB in the output stage to extract every last ounce of potential from the speakers and create soundscapes filled with subtlety. AAVA Volume Control Circuit Conventional preamplifiers use variable resistors to adjust volume, which can cause contacts to deteriorate and create rasping as well as increase noise at normal volume levels. AAVA, however, produces multiple, widely varying signals from the input signal and controls volume by changing the combination of those signals. This achieves minimum noise levels at all volume levels without any grit. ANCC (Accuphase Noise and distortion Cancelling Circuit) The E-4000 uses ANCC topology for the I-V converter amplifier. This innovative topology adds a sub-amplifier for effectively cancelling noise in the main amplifier circuit. The use of low-noise technology in the sub-amplifier (noise density: 1.5 nV / √Hz) further enhances the benefits of ANCC. By incorporating ANCC in the I-V converter amplifier and the balanced amplifier of the AAVA section, a further drastic reduction in noise is achieved, especially at low to medium volume level positions. Instrumentation Amplifier With balanced circuits in the signal input section, the amplification stage is comprised entirely of an instrumentation amplifier principle that equalizes input impedance on the + and – sides, for excellent external noise suppression, and providing optimal circuitry for this high-end audio amplifier. Balanced Remote Sensing Balanced remote sensing improves damping factor by feeding back the GND at the same time as the signal is output from the speaker terminals. Robust Power Amplification Stage The power amplification stage on both the left and right sides is equipped with a large heat sink and employs four-fold parallel push-pull power transistors driven in Class AB to provide rated, high-power output of 180 watts into 8 ohms and 260 watts into 4 ohms. High Damping Factor Brings Out the Full Potential of Speakers The damping factor represents the amplifier’s ability to drive the speakers. A damping factor of 800 (guaranteed) extracts the maximum potential from the loudspeakers. Power Supply Circuitry Designed for Optimum Stability A strong power supply featuring a massive toroidal transformer and two high-voltage, large filtering capacitors (40,000 μF/80 V) offers a stable power supply at all times. Why Choose The Accuphase E-4000 Integrated Amplifier? The Accuphase E-4000 is a refined integrated amplifier that blends elements from separate amp designs into a cohesive, high-performance unit. It’s part of the brand’s 12th generation of Class AB stereo amplifiers, with thoughtful engineering throughout. Volume control is handled by Accuphase’s AAVA system, which, alongside ANCC noise-cancelling circuitry, helps keep the signal clean and detailed at any listening level. The power amp stage uses a four-fold parallel push-pull setup in Class AB, supported by a robust power supply and balanced circuitry that keeps interference in check. A high damping factor ensures it partners well with demanding speakers, bringing out nuanced textures without fuss. Overall, the E-4000 feels like a careful evolution - solid, capable, and quietly confident in its design.
