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Fosi Audio IM4 Open-Back IEM

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Fosi Audio IM4 Open-Back IEM

Fosi Audio IM4 Open-Back IEM

Fosi Audio IM4 Open-Back IEM – Audiophile Clarity, Tuned Your Way

The Fosi Audio IM4 Open-Back IEM is engineered for listeners who crave natural tonality, wide soundstage, and long-session comfort. Built around a 10mm PU beryllium-coated dynamic driver, the IM4 uses an N52 dual-magnet, dual-chamber architecture to deliver fast transients, controlled bass, and articulate mids with airy, detailed highs.

Its open-back acoustic design, combined with internal damping wool, minimizes resonance and listening fatigue—resulting in a relaxed, spacious presentation that feels closer to high-end open headphones than conventional in-ear monitors. Whether you’re a critical audiophile, a music enthusiast, or a creator seeking realism, the IM4 offers a refined yet engaging Hi-Fi sound.

Precision-machined from 6063 CNC aluminum alloy, the IM4 showcases premium craftsmanship with a minimalist aesthetic. The lightweight, ergonomic shells (just 7g per earpiece) ensure all-day comfort, while the striking orange metal grille adds a distinctive visual identity.

Sound personalization is at the core of the IM4. With interchangeable brass and aluminum nozzles and three types of eartips (Balanced, Bass, Deep Bass), you can fine-tune the sound signature to match your music and preferences. A detachable 2-pin 0.78mm cable with high-purity silver-plated OFC conductors ensures reliable connectivity and future upgrade flexibility.

📋 Specifications

  • Shell Material: 6063 CNC Aluminum Alloy

  • Driver Unit: 10mm N52 Dual-Magnet, Dual-Cavity Dynamic Driver

  • Diaphragm: PU Beryllium-Coated

  • Sensitivity: 109dB

  • Impedance: 21Ω

  • Frequency Response: 20Hz – 20kHz

  • Cable: 4-Core, 392-Strand 5N OFC Silver-Plated Copper

  • Connector: 2-Pin 0.78mm

  • Audio Jack: 3.5mm Gold-Plated Plug

  • Weight (Per Earbud): 7g ±0.5g

  • Weight (With Cable): 38g ±1g

📦 What’s in the Box

  • Fosi Audio IM4 Open-Back IEMs

  • 3.5mm Detachable Cable

  • Carrying Pouch

  • User Manual & Quick Guide

  • Brass Nozzle

  • Balanced Ear Tips

  • Bass Ear Tips

  • Deep Bass Ear Tips

     

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From $33.72

Original: $112.41

-70%
Fosi Audio IM4 Open-Back IEM—

$112.41

$33.72

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Description

Fosi Audio IM4 Open-Back IEM – Audiophile Clarity, Tuned Your Way

The Fosi Audio IM4 Open-Back IEM is engineered for listeners who crave natural tonality, wide soundstage, and long-session comfort. Built around a 10mm PU beryllium-coated dynamic driver, the IM4 uses an N52 dual-magnet, dual-chamber architecture to deliver fast transients, controlled bass, and articulate mids with airy, detailed highs.

Its open-back acoustic design, combined with internal damping wool, minimizes resonance and listening fatigue—resulting in a relaxed, spacious presentation that feels closer to high-end open headphones than conventional in-ear monitors. Whether you’re a critical audiophile, a music enthusiast, or a creator seeking realism, the IM4 offers a refined yet engaging Hi-Fi sound.

Precision-machined from 6063 CNC aluminum alloy, the IM4 showcases premium craftsmanship with a minimalist aesthetic. The lightweight, ergonomic shells (just 7g per earpiece) ensure all-day comfort, while the striking orange metal grille adds a distinctive visual identity.

Sound personalization is at the core of the IM4. With interchangeable brass and aluminum nozzles and three types of eartips (Balanced, Bass, Deep Bass), you can fine-tune the sound signature to match your music and preferences. A detachable 2-pin 0.78mm cable with high-purity silver-plated OFC conductors ensures reliable connectivity and future upgrade flexibility.

📋 Specifications

  • Shell Material: 6063 CNC Aluminum Alloy

  • Driver Unit: 10mm N52 Dual-Magnet, Dual-Cavity Dynamic Driver

  • Diaphragm: PU Beryllium-Coated

  • Sensitivity: 109dB

  • Impedance: 21Ω

  • Frequency Response: 20Hz – 20kHz

  • Cable: 4-Core, 392-Strand 5N OFC Silver-Plated Copper

  • Connector: 2-Pin 0.78mm

  • Audio Jack: 3.5mm Gold-Plated Plug

  • Weight (Per Earbud): 7g ±0.5g

  • Weight (With Cable): 38g ±1g

📦 What’s in the Box

  • Fosi Audio IM4 Open-Back IEMs

  • 3.5mm Detachable Cable

  • Carrying Pouch

  • User Manual & Quick Guide

  • Brass Nozzle

  • Balanced Ear Tips

  • Bass Ear Tips

  • Deep Bass Ear Tips

     

Fosi Audio IM4 Open-Back IEM | The Audio Store