Apos has opened pre-orders on the SJY Argos ES Lab Hydra pairing, a new electrostatic headphone and matching integrated amplifier built to revive the mid-century Japanese hi-fi philosophy that STAX pioneered six decades ago with the SR-1.
The SJY Argos Electrostatic Headphones use a 580V Pro Bias driver for the speed, imaging and detail electrostatics are known for, while the Apos x ES Lab Hydra Integrated Amplifier drives electrostatics, planar magnetics, dynamic-driver headphones and passive speakers from a single chassis. Designed by Jeffrey Yin, the Argos pairs a vented 6,375 mm² driver with a CNC-machined aluminum housing, and both products are available now for pre-order ahead of an October 15 ship date.
The All-Seeing E-Stat: SJY Argos ES Lab Hydra Headphones
Named after Argos Panoptes, the many-eyed watcher of Greek myth, the SJY Argos is tuned to “take in the whole picture.” Its 580V Pro Bias electrostatic driver delivers the speed, separation and micro-detail the format is prized for, but SJY has leaned the tuning slightly warm, adding body to the bass, presence to vocals and texture across the midrange rather than chasing a clinical e-stat signature.
A vented driver design relieves pressure around the diaphragm, letting it move more freely while preserving the fast transient response electrostatics are known for. The headphone ships with a fully CNC-machined aluminum chassis and a 1.5 m cable terminating in the industry-standard 5-pin Pro Bias connector, and weighs 431g (491g with cable attached).
One Amplifier for Everything
Rather than building a single-purpose electrostatic energizer, ES Lab and Apos designed the Hydra to cover nearly every headphone and speaker type from one box. A low-noise generator supplies the 580V DC bias for 5-pin Pro Bias electrostatics, backed by a pair of Japanese-made step-up transformers dedicated to that high-voltage path. For conventional headphones and passive speakers, a Class AB composite amplifier built with high-precision Vishay MELF resistors and premium audio capacitors delivers 20W per channel into 8Ω, with 20dB of gain and THD+N rated at 0.0016% (1kHz, 10W into 8Ω).
A 4-pin XLR Direct output taps the power stage directly for demanding, low-sensitivity headphones, one balanced XLR and two single-ended RCA inputs cover source flexibility, and a bypass mode hands volume control over to an external DAC or preamp when needed. A protection circuit continuously monitors for DC offset and excessive output, muting automatically if either is detected.
Pricing and Availability
The SJY Argos ES Lab Hydra launch is running as a pre-order through Apos, with both pieces available separately or together. During the pre-order window, the Argos headphones are priced at $1,620 (down from a $1,800 regular price) and the Hydra amplifier at $1,980 (down from $2,200), putting the full electrostatic system at $3,600 against a $4,000 regular total. Apos expects to ship both products on or before October 15, 2026.
The launch continues Apos’ community-driven “Apos x” program, which pairs the retailer with independent designers to bring niche, collaboratively developed gear to market. Readers following the current wave of flagship headphone launches may also want to check our coverage of the Campfire Audio Chimera, another high-end headphone debuting this month. Full specifications and ordering are available on the Apos product announcement.
Key Specifications
- SJY Argos: 580V Pro Bias electrostatic driver, 6,375 mm² driver area, vented design
- SJY Argos: CNC-machined aluminum chassis, 5-pin Pro Bias connector, 1.5 m cable
- SJY Argos: weight 431g (491g with cable); designed by Jeffrey Yin
- ES Lab Hydra: 20W per channel into 8Ω, Class AB composite amplifier, 20dB gain
- ES Lab Hydra: THD+N 0.0016% at 1kHz/10W into 8Ω; frequency response 10Hz-50kHz (-3dB)
- ES Lab Hydra: one balanced XLR + two single-ended RCA inputs; 4-pin XLR Direct output
- ES Lab Hydra: dimensions 325 x 80 x 350 mm; weight 5.1 kg
- Pricing: $1,620 (Argos) and $1,980 (Hydra) in pre-order; ships on/before October 15, 2026
