The Sanyo Plus C-20 is a preamplifier that was part of Sanyo's Plus Series, produced from 1979 to 1982 in Japan. It features a sleek silver design consistent with other models in the series, presenting a visually appealing addition to any audio system. The Plus C-20 is designed to provide high-quality audio signal handling, allowing users to connect multiple audio sources for a more comprehensive sound experience. It was offered at an approximate original price of 550 DM, which reflects its positioning in the market during its time. The unit shares its underlying design with similar models from Siemens, highlighting its robust construction and functionality. For audio enthusiasts, the preamplifier plays a critical role in managing sound signals before amplification, making it an integral component in high-fidelity audio setups.