RADAR is a price search engine. We link to the original listing — we never sell direct. Transactions happen on the source site.
This US$649 asking price is fair for a nearly new Questyle SIGMA Pro, sitting just below the median of US$268 but well above the 25th percentile of US$117 in your database; however, since the listed item is the flagship SIGMA Pro (retail US$899) rather than the non-Pro SIGMA (retail US$599), the external retail anchor suggests this used price is actually a strong deal compared to new, especially given the "20 hours of use" claim. The timing matters because the SIGMA Pro is Questyle’s current flagship portable DAC, offering a clear performance upgrade over the older CMA18 and the non-Pro SIGMA, making early ownership on the used market attractive before inevitable price drift.
What makes this worthwhile is the SIGMA Pro’s reputation as a price-bracket-busting device that rivals flagship DACs costing nearly twice as much, delivering desktop-level sound in a portable form with Bluetooth and USB-C connectivity. The "nearly new" condition with minimal use implies original-owner care, likely including the magnetic leather case often bundled, and the unit’s cutting-edge current-feedback architecture ensures it remains relevant against future models. At US$649, you’re securing a top-tier portable amp at roughly 72% of retail with negligible wear—a genuine buying opportunity for enthusiasts who want flagship performance without the full new price.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Questyle Audio emerged in December 2012 from Shenzhen, China, founded by Jason Wong, an innovator whose university experiments in 2006 sparked the company's signature Current Mode Amplification (CMA) technology. This patented approach, filed globally just 18 months after launch, revolutionized amplifier design by adapting current amplification from high-speed communications to audio, prioritizing lossless, high-fidelity playback. Rooted in China's tech hub and manufactured by Foxconn, Questyle quickly built a global footprint through relentless R&D focused on overcoming environmental and technical barriers to pure sound.
The brand specializes in premium digital-to-analog converters (DACs), headphone amplifiers, and integrated desktop solutions, with standout portable dongles like the M12 and M15 embodying CMA alongside ESS flagship chips for PCM 384kHz/32-bit, DSD256, and MQA decoding. Their lineup emphasizes minimalist elegance, from compact mobile amps to robust desktop DAC/headphone amps like the Q192, delivering effortless, high-resolution performance without gimmicks.
Questyle holds a confident position in the high-end portable and desktop hi-fi market, earning acclaim as a premium challenger to established names through superior build, explosive detail, and V-shaped dynamics. Audiophiles praise its trouble-free excellence and technological edge, cementing its reputation among discerning buyers seeking innovative, no-compromise audio gear.
See all Questyle Audio listings on RADAR.
