Audio Store
coming soon
Shipping to:


You have no items in your shopping cart.

Westone Elite Series ES40 4-Driver Custom In-Ear Monitor

More Views

Westone Elite Series ES40 4-Driver Custom In-Ear Monitor

  • 4 Balanced Armature Drivers design

  • Passive 3-way crossover

  • Dual Bore Design

  • Isolation of more than 25dB ambient noise reduction

  • Specialized Cold Pour Acrylic technique for thicker and tougher shell

  • Unique Flex-Canal delivers maximum comfort and in-ear coupling

  • Removable MMCX Audio™ cable design

  • Custom fit, acrylic shell

  • Handcrafted in USA


* Required Fields



The ES40 is engineered to deliver a very balanced, powerful, and articulate sound stage, and delivers a breathtaking and immersive sound that makes the most of any recorded and mastered music. The new dual, low-frequency drivers create thick, rich, and immersive low-frequency information that accentuates todays recorded music, and is tough enough to survive on the world’s loudest stages. This combination creates an unbelievable listening experience that is sophisticated enough for the most discerning critical listener, but tough enough to survive in the world’s most demanding live-performance venues.

  • Westone Custom-Fit Technology
    Fully custom earpieces are cast, sculpted, and polished by hand from actual impressions of your ears, resulting in the best fit and acoustic seal possible.
  • Balanced Armature
    Westone’s balanced armature driver is significantly more compact and efficient than a traditional dynamic driver. Westone monitors provide enhanced sonic detail and frequency range that extends well beyond typical in-ear solutions.
  • Flex Canal
    A body temperature-reactive, semisoft earpiece canal additive that stays firm at room temperature for ease of insertion and then softens at body temperature, allowing increased comfort and acoustic seal for incredible noise isolation.
  • Cold Pour Acrylic
    Earpiece housings are cold-poured in acrylic for a thicker, more resilient acoustic enclosure. Expect increased durability, a more controlled response, and a lustrous appearance from this Westone technology.
  • Dual Bore
    With Westone’s Dual Bore technology, high and low frequency sound components are channeled through separate passages in the sound port and sum within your ear canal instead of the earpiece. The result is audibly more natural and provides a more convincing transition between frequency ranges.
  • EPIC Replaceable Cable
    Westone’s robust EPIC cable is constructed of bifurcated, high-flex, ultra-low resistance tinsel wire, reinforced with a special aramid fiber, and braided for ultimate durability, acoustic transparency, and isolation from mechanical cable noise. The MMCX Audio™ connector makes this solution conveniently user replaceable.
  • Handcrafted in the USA
    Meticulously built by a staff of dedicated artisans and lab techs, Westone’s USA products exhibit a level of craftsmanship that truly embodies America’s rich history of handmade artistry.
Technical Specifications

Additional Information

Package Contents

ES40 Custom-Fit In-Ear Monitors, MMCX Audio® Twisted Cable, Water-Proof, Watertight crush-resistant Pelican case, Cleaning Tool, Reusable Desiccant, Cleaning/Polishing Cloth, Oto-Ease Lubricant, User Manual, and 2-year warranty

Colour Customisable
Warranty 2 years (local)
Availability Available
Product Type Earphone
Style/Type Custom In-Ear (CIEM)
Driver Configuration 4-Drivers (Balanced Armature)
Frequency Response (Hz) 10 Hz - 20 kHz
Impedance (Ω) 28 ohms @ 1kHz
Sensitivity 112 dB SPL @ 1 mW
Headphone Design Closed-Back
Microphone None
Cable Style Detachable (MMCX)
Input Connectivity 3.5mm stereo
Additional Tech Specs
  • Passive Noise Attenuation: Up to 25dB
  • Driver: Four balanced armature drivers with passive three-way crossover
  • Cable: EPIC MMCX replaceable cable, 52”/128 cm (customisable)
User Reviews