RADAR is a price search engine. We link to the original listing — we never sell direct. Transactions happen on the source site.
Condition is listed as unknown, which makes the price harder to judge in practice, but US$499 is exactly the median of four recent comparable asks. It is fair rather than a bargain, sitting above the US$453 25th percentile and below the US$549 75th percentile; a fully tested example would justify that level.
The AP-1000 is a particularly capable vintage preamp, with versatile MM/MC phono, strong line-stage specifications, useful subwoofer and high-pass outputs, tone defeat, and a substantial dual-supply design. It has a reputation for a warm yet detailed presentation, good soundstaging, and an unusually strong phono section. At this price, confirm both channels, switches, controls, phono operation, and quiet volume tracking; evidence of service or original accessories would make the fair asking price more compelling.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Proton Electronic Industrial Co., Ltd. emerged from Taiwan in 1981, establishing its base in Banciao, Taipei-Hsien, as a manufacturer targeting the U.S. consumer audio market with high-quality components. Linked to Fulet Electrical, which produced notable NAD amplifiers, the brand launched around 1984 to expand into consumer electronics, including acclaimed TV monitors like the 600M and 602M models. By 2009, it remained active, building on a heritage of precision engineering from shared facilities with brands like NAD and Dynaco.
The company focused on premium hi-fi gear optimized for real-world performance, emphasizing tuners, receivers, amplifiers, and integrated systems that drove everyday loudspeakers with exceptional clarity. While not delving into headphones or cables, Proton's lineup prioritized robust playback under practical listening conditions, from radio reception to vinyl and cassette sources, earning praise for its engineering rigor in the 1980s.
Proton holds a solid reputation in vintage hi-fi circles as a mid-tier powerhouse, favored by collectors for its reliable, high-value sound that punched above its price point. Positioned as an accessible alternative to elite brands, it appeals to discerning buyers seeking durable, no-nonsense performers rather than boutique exotica, with ongoing interest in its schematics and restored units.
See all Proton listings on RADAR.
