RADAR is a price search engine. We link to the original listing — we never sell direct. Transactions happen on the source site.
With unknown condition, £183 looks good value rather than a stretch for this Stax driver. Recent used asking prices I can see are around £440 in the UK, with other used examples generally landing in a mid-hundreds bracket, so this sits comfortably below typical market levels and reads as a bargain if it’s working properly.
That’s why it’s worth a look: the SRM-313 is a well-regarded solid-state electrostatic energizer, with a clean, direct presentation and enough drive for Lambda-class Stax headphones. At this price, the upside is strong even without original packaging, but do confirm it powers up cleanly, switches bias correctly, and has no channel imbalance or crackle after warm-up, since age-related service issues matter more on older electrostatic amps.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Stax traces its origins to 1938 in Tokyo, Japan, when Naotake Hayashi founded Showa Kouon Co., Ltd. in Chiyoda-ku. Initially focused on wax disc recording, metal master production, and audio equipment for film soundtracks, the company evolved through the postwar era. In 1950, it launched its first high-frequency condenser microphone, adopted by NHK, and renamed itself STAX Co., Ltd. in 1963, honoring its pioneering Stax-1 mic. A brief suspension in 1995 due to economic pressures gave way to revival, preserving its legacy under family leadership.
The brand specializes in electrostatic headphones, known as "EARSPEAKERS," debuting with the world-first SR-1 in 1960. This innovation spawned enduring lines like the SR series, produced for decades with incremental refinements for superior resolution and staging. Stax complements these with dedicated electrostatic amplifiers and select accessories, eschewing conventional speakers, turntables, DACs, or cables to hone its transducer expertise.
Stax commands a niche high-end position among audiophiles and professionals, revered for unmatched transparency and fidelity that rivals cost-no-object loudspeakers. Its 85-year heritage cements it as a boutique icon in electrostatic technology, far from mass-market fare, appealing to discerning buyers seeking pinnacle sonic transduction.
See all Stax listings on RADAR.
