By developing Class A+ operation that provided amazing 350 W + 350 W output power, Technics aimed to achieve the highest level of power amp performance with the SE-A1. Theoretically, Class A operation does not generate switching distortion or crossover distortion. On the other hand, it is low in efficiency, so it is difficult to produce a high-power Class A amp. The Class A+ operation employed in the SE-A1 was similar to the Class A operation, which constantly requires electric current, but with floating ground potential. This system supplied high voltage from a separate power supply amp as needed in sync with the audio signal amplitude. This achieved high output power without using a forced air cooling fan, thus enabling a compact housing. The SE-A1 was a full-fledged DC amp, and boasted excellent waveform transmission performance. The active thermal servo circuit suppressed DC drift. The power supply section featured a dual monaural structure with four power supply units per channel for a total of eight power supply units. The peak meter was a quick-response type. The SE-A1 and SU-A2 were made-to-order, and only one unit was produced per day. The SE-A1 developed in pursuit of the highest possible performance had a considerable impact on the industry.