Inheriting many outstanding technology features of the A-200, the A-70 represents a full model change from the A-65, ready to take its place as the ultimate pure class A stereo power amplifier. While reflecting this tradition, the A-70 also implements latest technology such as the ultra low-noise instrumentation amplifier principle realized in a discrete configuration, along with optimized signal input and power amplification stages, resulting in an astonishing 127 dB S/N ratio (at -12 dB gain), surpassing even the formidable earlier Accuphase stereo amplifier lineup.
The output stage of the A-70 features power MOS-FETs renowned for their excellent frequency response, sonic performance, and superior reliability. In the output circuitry, ultra-heavy-gauge edgewise coils with a surface area more than three times larger than conventional units, combined with MOS-FET switches are used in place of relays, to eliminate mechanical contacts and improve long-term reliability. Top-grade materials, sophisticated circuit pattern technology, and various other measures result in low impedance and enable the realization of a damping factor of 800, which represents a two-fold improvement over the A-65.