Apos ARGOS and HYDRA

Put a New Spin on Electrostatic Hi-Fi

Apos launches SJY ARGOS headphones and HYDRA amplifier

Apos has introduced the SJY ARGOS electrostatic headphones and Apos x ES Lab HYDRA integrated multi-output amplifier. HYDRA is a hardware collaboration with ES Lab. Apos is a US-based specialist audio retailer and product-development platform.

Georg S. Kuklick

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Apos introduced the SJY ARGOS electrostatic headphones and Apos x ES Lab HYDRA integrated multi-output amplifier on 18 August 2026. The regular price for the ARGOS is US$1,800. Its preorder price is US$1,620. HYDRA carries a US$2,200 regular price and a US$1,980 preorder price.

The ARGOS operates at 580 V Pro Bias and has a 6,375 mm² driver area. Its capacitance is 130 pF with the attached 1.5 m cable. The headphone uses a 5-pin Pro Bias electrostatic connector. The headphone has a CNC-machined aluminum chassis and weighs 491 g including its cable.

HYDRA uses a Class AB composite amplifier topology with 20 dB of gain. It supports electrostatic, planar-magnetic and dynamic headphones plus passive speakers; conventional-headphone impedance compatibility spans 16 Ω to 300 Ω. Frequency response is 10 Hz to 50 kHz at 1 W and -3 dB. THD+N is 0.0016% at 1 kHz and 10 W into 8 Ω.

For electrostatic headphones, HYDRA supplies 580 V DC bias; its attenuated headphone output delivers 200 mW into 32 Ω. The speaker/direct output delivers 20 W per channel into 8 Ω and 5 W per channel into 32 Ω. That output is rated at 1,000 mW per channel into 155 Ω and 500 mW per channel into 300 Ω. Source connections comprise one balanced XLR input and two single-ended RCA inputs.

The amplifier measures 325 × 80 × 350 mm and weighs 5.1 kg. Both products have a shipping target of 15 October 2026.

Key specifications

ARGOS driver type

Electrostatic

ARGOS bias voltage

580 V Pro Bias

ARGOS driver area

6,375 mm²

ARGOS capacitance

130 pF with 1.5 m cable

ARGOS connector

5-pin Pro Bias electrostatic

ARGOS cable

Attached, 1.5 m

ARGOS chassis

CNC-machined aluminum

ARGOS weight

431 g; 491 g including cable

HYDRA supported loads

Electrostatic, planar-magnetic and dynamic headphones, plus passive speakers

HYDRA amplifier topology

Class AB composite amplifier

HYDRA electrostatic bias voltage

580 V DC

HYDRA speaker/direct output power

20 W/channel at 8 Ω; 5 W/channel at 32 Ω; 1000 mW/channel at 155 Ω; 500 mW/channel at 300 Ω

Data Source

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© 2026 Neo Digital Magazines llc. All rights reserved.

Built by humans with AI in Berlin, New York, and Vienna.

© 2026 Neo Digital Magazines llc. All rights reserved.

Built by humans with AI in Berlin, New York, and Vienna.

© 2026 Neo Digital Magazines llc. All rights reserved.