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64 Audio A4t Four Drivers Custom IEM Earphones

  • Quad driver custom-fit in-ear monitor (IEM) featuring tia technology
  • Balanced and neutral sound signature with impressive clarity
  • 1 tia High, 1 Mid, 2 Low drivers with 4-way crossover
  • Modular apex technology relieves air pressure providing superior sound
  • Fully customizable and custom-built from unique ear impressions

  • 64 Audio A4t

    Custom in-ear monitors are made to order and custom crafted for every individual user making the ordering process different from standard earphones. It only takes a few steps to get your personal custom moulded in-ear monitors made. Click the link to learn more about the Ordering Process, or contact the Hifiheadphones support team.

    64 Audio A4t is the entry point for anyone seeking the remarkable smoothness and extension of the tia technology. Built on the foundation of 64 Audio's successful 4-driver design, the new A4t delivers an immersive listening experience with a lively mid-range and powerful bass. Its sound signature is balanced and neutral, shining forth with a new level of clarity thanks to the tia driver and the tia single-bore that aids in removing unwanted resonance and distortion.

    Featured in the A4t is apex, a pneumatically-interactive vent that relieves fatigue-causing sound pressure inherent in other earphone designs. Also featured is LID technology, ensuring the A4t maintains its sound signature regardless of the source - perfect for musicians and music lovers plugging into a variety of equipment.

    Like all 64 Audio Custom IEMs, the A4t monitors are customizable and are hand-built from your uniquely shaped ear impressions. They are inherently noise isolating and are designed to work with a wide range of personal audio devices as well as all hard-wired and wireless monitor systems.

    Immersive listening.


    64 Audio A4t

    Custom Ear Impressions
    A great-fitting pair of custom in-ear monitors begins with a great pair of ear impressions, which are taken by a hearing professional called an audiologist. In the ordering process we will put you in touch with with your nearest UK audiologist to get the process started.

    Custom Design Options
    All 64 Audio custom IEMs are hand-built to order and fully customisable. Bespoke options include faceplate colour and artwork, cable length and colour, Apex modules, storage case customisation, and more - the choices are endless. Be aware that some options will increase the final price. For questions please contact us.

    Custom Monitor Ordering Process
    It only takes a few steps to get your personal custom moulded in-ear monitors made. The estimated built time for custom moulds is around 3 weeks after the ear impressions are received by 64 Audio. Click the link to get the Ordering Process started for your personal custom in ear monitors.



    • Transducer Type: Four precision balanced armature drivers
    • Transducer Configuration: 1 tia high, 1 hi-mid, 1 low-mid, 1 low
    • Freq. Response: 16Hz - 20kHz
    • Sensitivity: 111 dB/mW
    • Impedance: 11Ω @ 1kHz
    • Crossover: Integrated 4-way passive crossover
    • Isolation: -20dB w/ m20 module, -15dB w/ m15 module



    • Quad driver custom-fit in-ear monitor (IEM) featuring tia technology
    • Balanced and neutral sound signature with impressive clarity
    • 1 tia High, 1 Mid, 2 Low driver with 4-way crossover
    • Tia Single Bore eliminates unwanted tube resonance
    • Internal modular apex technology eliminates pneumatic pressure
    • LID Linear Impedance Design retains intended frequency response
    • Hypoallergenic hard acrylic shells
    • Fully customizable and custom-built from unique ear impressions
    • 1.2m or 1.6m detachable professional audio cable
    • Warranty: 2-Year Parts and Labour



    • 64 Audio A4t Custom IEM Earphones
    • 64 Audio personalized protective case
    • Dehumidifier
    • Cleaning tool
    • Shirt clip
    • 1.2m or 1.6m detachable professional cable
    • m20 or m15 apex Modules
    • Round sticker


    1. Brand64 Audio
    2. Connectivity TechnologyWired
    3. Detachable CableYes
    4. Driver TypeBalanced Armature
    5. Frequency Response16Hz - 20kHz
    6. Headphones TechnologyBalanced Armature
    7. Headphones TypeHeadphones - binaural
    8. Headphone Fit TypeCustom Mould
    9. Impedance11Ω
    10. Manufacturer Warranty2 Years
    11. Number of driversQuad Drivers
    12. Part NumberA4t
    13. Product TypeEarphones
    14. Recommended useDigital audio player;Hi-Fi;Portable audio system;Studio
    15. Feature keywordComfortable;Ear Canal;Hi-Fi;IEM;In Ear;Monitor;Noise Isolation;Portable;Professional;Studio
    16. Sensitivity111dB
    17. Sound Output ModeStereo
    18. Headphone ApplicationDJ;Gaming;On Stage;Studio;Work
    19. Headphones Form FactorCustom Mould
    20. Included AccessoriesProtective case, Dehumidifier, Cleaning tool, Shirt clip, Professional cable, apex Modules, Sticker
    21. Sound Output ModeStereo