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At US$900, this Onkyo M-506RS asks exactly the median of our recent comparable USD listings, where the 25th percentile sits at US$775 and the 75th at US$1,300, making it a fair price rather than a bargain. New in 1983, this Grand Integra unit cost ¥188,000 (roughly US$780 at then-current rates), so today’s US$900 reflects modest appreciation for a rare, high-performance vintage amp.
The M-506RS is well-regarded for its super-turbo servo design delivering 140W–190W per channel with astonishingly low distortion (0.0015% at 70W) and a 1Hz–100kHz bandwidth. Its 20.5kg build, FET output stage, and 120dB signal-to-noise ratio make it a musical, stable power source that still commands respect among vintage enthusiasts. Since the price is fair and the listing notes unknown condition, a recapped unit or one with original accessories would be a clear buying opportunity; if it’s untested, budget for a professional recap, but the upside remains strong for a clean example.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Onkyo traces its roots to postwar Japan, founded in 1946 in Osaka by Takeshi Goda, an engineer at Matsushita Electric who envisioned high-quality Japanese loudspeakers. Initially established as Osaka Denki Onkyo K.K., the company began production in 1948 with the acclaimed ED-100 speaker featuring a 25 cm driver, quickly building a reputation through LP concerts and innovative designs that resonated with audiophiles.
The brand excels in premium home audio, renowned for AV receivers, hi-fi amplifiers, and surround sound speakers that deliver exceptional clarity and power. Its portfolio spans turntables, DACs, headphones, and cables, bolstered by acquisitions like Pioneer's home electronics division in 2015, enabling cutting-edge integrations such as internet radio and high-resolution streaming.
Onkyo holds a solid mid-tier position in the hi-fi market, prized by discerning buyers for reliable performance and value rather than ultra-high-end exotica. Despite bankruptcy challenges in the late 2010s, its revival under new ownership preserves a legacy of technological innovation and pure sound enjoyment, appealing to both vintage enthusiasts and modern home cinema setups.
See all Onkyo listings on RADAR.
