Luxman has successfully upgraded sound quality by adopting designs to choose each earth lines, using high-purity gold-plated terminals, and arranging discrete wiring layouts for avoiding noise through circuit loops. The AS-44 and AS-55 use 6N (00.99997% copper) wire in their wiring diagrams to offer high performance compared to that of high quality separate amplifiers. The AS-4III and AS-5III, modern refined models of the long-selling AS-4 and AS-5 have incorporated more headphone terminals and index space for enhancing operating ease. The AS-50R now offers a remote control, enabling users to easily select more than one system without having to get up and disturb their listening.