STAX SR-003MK2 In-Ear Earspeaker

£295.00 inc. VAT

Trade-in available.

The SR-003 are a pair of electrostatic in-ear earspeakers (earphones) from STAX Audio, delivering improved performance thanks to a redesigned inner structure and greater comfort thanks to reduced weight.

Available in Black finish only.



* Usually ships within 1-3 business days. See exceptions

SKU: USV-STAX-SR003MK2 Categories: , Tag:



The SR-003MK2 is a 5-pin PRO bias in-the-ear earspeaker (the STAX term for earphones). They can be driven by connecting to a driver unit having 5-pin PRO bias output socket.

The redesigned ear canal type structure of the SR-003 enables you to enjoy excellent electrostatic sound quality without covering your ears, plus they are 15% lighter than the S-001/MK2, which benefits prolonged listening sessions.

Why call them "Earspeakers"?

STAX prefers to call its headphones Earspeakers – they say that such ultra-high fidelity devices for reproducing music can only be compared with the best loudspeakers, not other headphones, thus the term earspeaker is more descriptive of their contribution to today’s most advanced level of sonic transduction.

Electrostatic technology

Electrostatic transducers consist of two parallel-arranged fixed electrodes with a very thin high-polymer film diaphragm sandwiched and suspended in the middle of the electrodes.

The diaphragm is supplied with the biasing voltage from the energizing adaptors or from the driver unit.

When the fluctuating voltage of the audio signal is applied to the electrodes, the diaphragm is pulled by one electrode (which has the opposite charge of the diaphragm) and simultaneously pushed by the other electrode (which has the like charge of the diaphragm).

This continuous flow of alternating voltage causes the diaphragm to vibrate in faithful compliance with the amplifier output without lag, assuring undistorted sound waves. This is why the STAX electrostatic earspeakers sound so good.

Electrostatic driver required

Electrostatic reproduction has many quality advantages, however such units cannot be used directly with a conventional headphone jack, and require a special electrostatic amplifier (driver) unit.

The vibrating diaphragm requires Bias voltage of 580 V (almost no current). Relatively high signal voltage to the fixed pole (up to 300-600 V) must be supplied as push-pull, a rather special electrical signal. The STAX series of driver units are dedicated amplifiers strictly for STAX headphones.


  • Re-designed ear piece with 3 silicone ear bud sizes.
  • 15% lighter than the S-001/MK2 results in further resolution, transparency and purer listening pleasure.


  • Type: Push-Pull electrostatic circular sound element, in-ear type enclosure
  • Frequency Response: 20-20 kHz (4 dB)
  • Capacitance: 44 pF (including cable)
  • Sensitivity: 110 dB / 100 V RMS 1 kHz
  • Bias Voltage: 550-580 V DC
  • Ear Pads: Silicone earbuds (Small, Medium, or Large available. Medium included)
  • Cable: Parallel 6-core, 1.5 metre full length
  • Weight: 0.4 oz (11.34 g) without cable / 1 oz (28.35 g) with cable

Full STAX Range Available

Unilet Sound & Vision are official retail partners for STAX Audio, providing sales, advice and assistance on their entire range of high-quality audio products. Please do get in touch if you would like a demonstration or wish to purchase.

More Information

Additional information

Weight 0.03 kg


Purchase Options

Click & Collect, Trade-In Available



Founded in 1938, STAX brought the world's first electrostatic headphone to market in 1960. Today they continue their long tradition by offering the finest audio products for both professional and audiophile applications.

All STAX headphones are referred to as "earspeakers" - the company states that such ultra-high fidelity devices can only be compared with the best cost-no-object loudspeakers, not other headphones. Their unique amplifiers, earspeakers and drivers are highly sought-after products, and extremely well considered by aficionados in the audio industry.

Unilet Sound & Vision are one of the oldest STAX dealers in the UK, and one of the very few official outlets stocking their products. Do get in touch with us if you would like to audition the range, or need advice or assistance with choosing the right system for your needs.

STAX | Unilet Sound & Vision


There are no reviews yet.

Be the first to review “STAX SR-003MK2 In-Ear Earspeaker”

Your email address will not be published. Required fields are marked *