Accuphase A-75 – Stereo Power Amplifier

Description

Tecnifi announces the availability of the power-packed Accuphase A-75 Stereo Power Amplifier. Instrumentation amplifier topology using discrete semiconductors realizes ideal gain allocation. Balanced Remote Sensing optimizes the efficiency of negative feedback. 10-parallel push-pull configuration in the power amplification stage. The overall result is an outstanding S/N ratio and amazingly high damping factor. Furthermore, constant-voltage drive manages even drastic speaker impedance fluctuations with utmost ease. Power MOS-FETs and other judiciously selected components and materials make this Pure Class A Stereo Power Amplifier a total delight to experience.

High S/N ratio results in sparkling clarity
The Accuphase A-75 uses a balanced instrumentation amplifier circuit configuration throughout all amplification stages, minimizing susceptibility to noise and ensuring outstanding characteristics. The signal input stage is configured with discrete semiconductors as a push-pull circuit. This makes it possible to allocate a high gain of 22 dB (factor of approx. 12.6) to this section and conversely keep the gain of the power amplification section to a low 6 dB (approx. x2.0). As a result, even large signal amplitudes are conveyed accurately from the signal input stage to the power amplification stage, and noise components processed in the amplification stage are kept low. Compared to the previous model, this results in a noise reduction of 11%. S/N ratio is rated at an astonishing 122 dB (at max gain setting), which manifests itself in superb sonic clarity.

Output power characteristics suitable for constant voltage noise
A massive toroidal power transformer and large filtering capacitors (100,000 μF x 2) in the power supply ensure that plenty of power is available for handling high amplitude input signals, and large heat sinks efficiently dissipate any excess thermal energy. As a result, the power amplification stage is rated for a continuous 60 watts into 8 ohms, 120 watts into 4 ohms, 240 watts into 2 ohms and 480 watts into 1 ohm (music signals). This linear power progression demonstrates that constant voltage drive has been successfully realized. The maximum output rating is 131 watts into 8 ohms, 232 watts into 4 ohms, 370 watts into 2 ohms and 547 watts into 1 ohm (music signals). Although a Pure Class A Stereo Power Amplifier, the A-75 can easily drive even large and demanding speakers.