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    U4s


    Universal

    Fitting

    4

    Drivers

    $1,099.00

    USD


    U4s


    Universal

    Fitting

    4

    Drivers

    $1,099.00

    USD


    U4s


    Universal

    Fitting

    4

    Drivers

    $1,099.00

    USD

    U4s

    U4s

    Universal

    Fitting

    4

    Drivers

    $1,099.00

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    Add to Cart

    Ships In 2-3 Business Days

    Universal

    Fitting

    4

    Drivers

    $1,099.00

    Ships in 1-4 Business Days

    A quad driver hybrid UIEM featuring ground-breaking patented technologies originally developed for our flagship products in order to bring a wider audience closer to their music. U4s explores a bold new color aesthetic for 64 Audio. The Slate Blue shell color was influenced by some of the world’s most beautiful blue- dial timepieces while the unique faceplate pattern is inspired by Muonionalusta meteorite fragments. Both the faceplate and shell’s illuminant properties give it a unique tone in varying lighting conditions.

    Sound

    U4s sounds light on its feet while effortlessly delivering physically engaging sub-bass without bleeding into the mid-bass. Balanced mid frequencies and a pleasant high-mid band respond well to a wide array of music and recording styles at every volume level; present but not fatiguing. The tia high-driver’s open airy quality couples with the extended sound-stage provided by apex for a lifelike sonic experience.

    Its ergonomic anodized aluminum shell houses a single dynamic driver, two balanced-armature drivers, and one patented tia driver; all weaved together with our patented Tia, LID, and Apex technology. The four-way crossover is elevated with the use of our proprietary electrical low-pass filter; reducing low- frequency distortion. The assortment of included apex modules and ear tips are an invitation to further shape the sound based on preference and source material while the ultra- low impedance premium silver-plated copper cable ensures unimpeded signal transmission. The dissemination of tia technology within our product range brings that classic 64 Audio sound signature to a new price-point.

    Featured Technology

    Tubeless In-Ear Audio (tia) is a patented IEM design methodology that aims to reduce unwanted resonance and distortion for a transparent and lifelike sound signature. The tia system is comprised of three major elements: open balanced armature tia drivers, the tia single-bore design, and tia acoustic chambers. U4s features two major elements of the tia system: the tia driver and the tia single-bore design.

    Air Pressure Exchange (Apex) is a patented vent that releases air pressure in a sealed ear canal all while retaining standard IEM levels of isolation; enabling musicians and music enthusiasts to listen more comfortably for longer. This venting alleviates listener fatigue and allows for a much more realistic soundstage. Apex comes in three module variations for U4s: mX, m15, and m20.

    Linear Impedance Design (LID) is a patented circuit that corrects the non-linear electrical resistance of the multiple driver-sets comprising this 4 driver IEM. Varying source amplifier output impedance in devices like smartphones, body packs, DAC/amps, and DAPs typically results in varying frequency response across them, depending on the increase in resistance. Restoring proper interaction with the source and preserving the desired sound signature enables a consistent reliable sound.

    A crossover circuit replacing traditional acoustic dampers which can introduce unwanted distortion through vibration and air turbulence. Rather than using acoustic dampers to filter unwanted frequencies after the driver produces them the electrical low pass filter lowers distortion by eliminating unwanted frequencies before they reach the driver.

    Tubeless In-Ear Audio (tia) is a patented IEM design methodology that aims to reduce unwanted resonance and distortion for a transparent and lifelike sound signature. The tia system is comprised of three major elements: open balanced armature tia drivers, the tia single-bore design, and tia acoustic chambers. U6t features two major elements of the tia system: the tia driver and the tia single-bore design.


    Air Pressure Exchange (Apex) is a patented vent that releases air pressure in a sealed ear canal all while retaining standard IEM levels of isolation; enabling musicians and music enthusiasts to listen more comfortably for longer. This venting alleviates listener fatigue and allows for a much more realistic soundstage. Apex comes in three module variations for U4s: mX, m15 and m20.


    Linear Impedance Design (LID) is a patented circuit that corrects the non-linear electrical resistance of the multiple driver-sets comprising this 6 driver IEM. Varying source amplifier output impedance in devices like smartphones, body packs, DAC/amps, and DAPs typically results in varying frequency response across them, depending on the increase in resistance. Restoring proper interaction with the source and preserving the desired sound signature enables a consistent reliable sound.

    All of our custom and universal IEMs are Designed, Assembled, and QC’d by highly skilled technicians in the United States using components sourced both domestically and globally from trusted suppliers.

    Specifications

    1 tia High Driver – 1 High-Mid Driver – 1 Mid Driver – 1 Dynamic Low Driver

    10hz – 20kHz Frequency Response

    107 dB/mW Sensitivity @1kHz

    Integrated 4-way Passive Crossover

    11Ω Impedance @1kHz

    Apex Technology Isolation: -20dB, -15dB, -10dB

    Specifications

    1 tia High Driver – 1 High-Mid Driver – 1 Mid Driver – 1 Dynamic Low Driver

    10hz – 20kHz Frequency Response

    107 dB/mW Sensitivity @1kHz

    Integrated 4-way Passive Crossover

    11Ω Impedance @1kHz

    Apex Technology Isolation: -20dB, -15dB, -10dB

    Designed, Assembled, and QC’d by highly skilled technicians in the United States using components sourced both domestically and globally from trusted suppliers.

    Black Premium Cable

    0.23 Ohms Total Impedance

    7 x 7 x 4 Multi-Twist

    Silver Plated OCC Copper Wire

    26 AWG

    Terminated in 3.5mm

     

    Included

    U4s Universal In-Ear Monitors

    64 Audio Premium Leather Case

    TrueFidelity Foam Ear Tips (S,M,L)

    SpinFit Silicone Ear Tips (S,M,L)

    Silicone Ear Tips (S,M,L)

    3.5mm Black Premium Cable

    Apex Modules: m20, m15, mX

    Cable Clip

    Cleaning Tool

    Round Sticker

    Sound

    U4s sounds light on its feet while effortlessly delivering physically engaging sub-bass without bleeding into the mid-bass.

    Balanced mid frequencies and a pleasant high-mid band respond well to a wide array of music and recording styles at every volume level; present but not fatiguing.

    The tia high-driver’s open airy quality couples with the extended sound-stage provided by apex for a lifelike sonic experience.

    Specifications

    1 tia High Driver – 1 Dynamic Low Driver

    20hz – 20kHz Frequency Response

    98 dB/mW Sensitivity

    Integrated 2-way passive crossover

    9Ω Impedance

    -12dB isolation apex core technology

    Featured Technology

    Rather than constricting the sound of the drivers by fitting a tube onto them, Duo’s complete Tia System reduces unwanted resonance and distortion by allowing the 9mm Dynamic Driver + Tia High Driver to radiate freely into the single large Tia bore with no obstructions to the front of the drivers.

    Apex Core is a deeper understanding of air movement within an earphone system. Duo’s faceplate features a striking perforated grill that leaves the shell of the IEM open to the outside atmosphere for a less obstructed airflow resulting in an effortless reproduction of music and minimal physical fatigue.

    Due to the high crossover point between the two drivers, Wave Sync was developed to ensure coherence; another industry first. By using a type of “all-pass” filter, we’re able to introduce a crossover while correcting for time without having to change the physical distance between the drivers.





    Specifications

    • 1 tia High Driver – 1 High-Mid Driver – 1 Mid Driver – 1 Dynamic Low Driver

    • 10hz – 20kHz Frequency Response

    • 107 dB/mW Sensitivity @1kHz

    • Integrated 4-way Passive Crossover

    • 11Ω Impedance @1kHz

    • Apex Technology Isolation: -20dB, -15dB, -10dB

    Designed, Assembled, and QC’d by highly skilled technicians in the United States using components sourced both domestically and globally from trusted suppliers.

    Specifications

    1 tia High Driver – 1 Dynamic Low Driver

    20hz – 20kHz Frequency Response

    98 dB/mW Sensitivity

    Integrated 2-way passive crossover

    9Ω Impedance

    -12dB isolation apex core technology

    Included

    • U4s Universal In-Ear Monitors

    • 64 Audio Premium Leather Case

    • TrueFidelity Foam Eartips (S,M,L)

    • SpinFit Silicone Eartips (S,M,L)

    • Silicone Eartips (S,M,L)

    • 3.5mm Black Premium Cable

    • Cable Clip

    • Cleaning Tool

    • Apex Modules: m20, m15, mX

    • Round Sticker

     



    U4s

    Universal Fit - 4 Drivers

    $1,099

    Ships in 1-4 Business Days

    U4s

    Universal Fit - 4 Drivers

    $1,099.00

    USD

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