Accuphase A-36 Class-A Stereo Power Amplifier

Description

Tecnifi announces the availability of the power-packed Accuphase A-36 Class-A Stereo Power Amplifier. The new A-36 inherits many of the outstanding design technology features developed for the higher-end models. It redefines the baseline for pure class-A power amplifiers and embodies the same unflinching attention to detail and dedication to sound quality for which Accuphase is justly famous. In the output stage, power MOS-FETs renowned for their excellent frequency response, sonic performance, and superior reliability are used in a triple parallel configuration and driven in pure class A. This is sustained by the strong power supply featuring a massive transformer and two large 47,000μF filtering capacitors. Output power in each channel is rated for an impressive 150 watts into 1 ohm, 120 watts into 2 ohms, 60 watts into 4 ohms, and 30 watts into 8 ohms. Even speakers with ultralow impedance or drastic fluctuations in impedance curve can be driven reliably by this impressive amplifier. In the output circuitry, MOS-FET switches are used in place of relays, to cut out mechanical contacts and improve long-term reliability.

Instrumentation amplifier topology for fully balanced signal paths
The instrumentation amplifier principle ensures that all signal paths from the inputs to the power amp stage are fully balanced. This not only results in excellent CMRR (Common Mode Rejection Ratio) and minimal distortion, it also makes the amplifier highly resistant against external noise and other external influences. The result is a drastic improvement in operation stability and reliability.

Current feedback principle assures excellent phase characteristics in high range
The A-36 uses the output signal current rather than voltage for feedback. Since the impedance at the current feedback point is very low, there is almost no phase shift. A minimal amount of NFB therefore results in maximum improvement of circuit parameters.

Further refined MCS+ topology for even lower noise
Accuphase’s original MCS (Multiple Circuit Summing) principle uses a number of identical circuits connected in parallel to achieve superior performance characteristics.