RADAR is a price search engine. We link to the original listing — we never sell direct. Transactions happen on the source site.
£746 looks like a strong buy, not an ambitious ask: recent used comps for the HA4 cluster around roughly £1,000 to £1,100, with a broader current used spread that reaches higher when condition and presentation are strong. At that level, this listing sits comfortably below the going used market and closer to bargain territory than merely fair.
The appeal is straightforward: this is a serious class-A headphone amp that also works as a compact preamp, and it has a long-standing reputation for a calm, detailed, non-fatiguing presentation with plenty of drive. At £746, a clean example is the kind of piece that can be bought and enjoyed rather than flipped, and the only things worth checking are the usual age-related basics — functionality, cosmetics, and whether the original box, manual, and remote are included if you care about resale.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Sugden Audio: British Heritage and Class A Excellence
Sugden Audio was founded in 1967 by James Edward Sugden in Cleckheaton, West Yorkshire, as a division of Research Electronics, his earlier scientific instrument manufacturing company. Sugden's background in precision engineering and broadcast equipment design at EMI informed the company's founding philosophy of meticulous craftsmanship and sonic integrity. The brand has remained rooted in British manufacturing throughout its history, maintaining its West Yorkshire base and family involvement through successive generations, most recently under the stewardship of the Miller family alongside the long-term Sugden team.
The company is synonymous with Class A solid-state amplification, having pioneered this technology with the legendary A21 integrated amplifier in 1967—widely recognized as the first commercially produced pure Class A solid-state amplifier. Sugden's product portfolio centers on high-end electronics, particularly integrated and power amplifiers, alongside preamplifiers. The brand's design philosophy emphasizes minimalism and musicality over unnecessary features, captured in their tagline "Rescuing Music from technology." All products are hand-built to exacting standards, reflecting Sugden's commitment to quality over mass-market appeal.
Sugden occupies a distinctive position in high-end audio as a niche boutique manufacturer with deep credibility among serious audiophiles and collectors. The A21 remains in continuous production—now in its A21a iteration—making it one of the longest-running models in specialist hi-fi. Vintage Sugden equipment has become highly sought-after by collectors, while contemporary designs maintain the brand's reputation for sonic excellence and engineering precision that has defined British audio craftsmanship for nearly six decades.
See all Sugden listings on RADAR.
