• Nano diaphragm, studio-grade sound
• 97mm driver, extreme detail resolution
• Walnut build, premium craftsmanship
• Open-back, expansive soundstage accuracy
• Pair it with: 4.4mm standard cableXLR adaptorreplacement earpads

Fosi Audio i5

Open-Back Planar Magnetic Headphones for HiFi Audiophiles

Democratizing Planar Sound

The i5 was born from our mission to make planar magnetic headphones more accessible—without compromising on sound quality, comfort, or design. Over a year of in-house development and acoustic tuning led to a headphone that delivers exceptional clarity, low distortion, and lifelike detail.

• Transducer Type: Planar Magnetic Transducer
• Maximum SPL: ≥ 120 dBSPL
• Frequency Response: 10 - 50,000 Hz; THD: < 1% @100dBSPL
• Sensitivity: 98 dB/mW @1kHz; Nominal Impedance: 28 Ω
• Recommended Power: ≥ 500 mW

Immersive Listening, Pure Original Sound

Nano-thin diaphragm, stealth magnets & precision acoustics deliver high-res, low-distortion sound.

97mm Ultra-Large Diaphragm

Nano-precision ultra-thin diaphragm delivers faster, clearer, layered sound.

Symmetrical Arranged High-Strength Magnetic Matrix

22 symmetric N50 magnets ensure ultra-low distortion, delivering pure, natural sound.

Sputtered Coating Technology

1.3μm silver-coated diaphragm via precision sputtering delivers refined, durable sound.

Rigid High-Transparency Acoustic Mesh

Rigid rear mesh ensures stable damping, smooth response,and open soundstage with minimal resistance.

Durable Memory Metal Headband

High-strength memory metal headband stays shaped, lightweight & flexible for pressure-free comfort.

Dual-Axis Earmuff Arms for a More Precise Fit

Multi-directional rotation adapts to any head shape for secure, custom comfort.

Breathable Skin-Friendly Earpads

Perforated leather & breathable fabric earpads stay cool; memory foam delivers all-day comfort.

Stepless Silicone Adjustment

Silky-smooth silicone slider enables precise, effortless headband adjustments.

Ultimate Hi-Fi Stack: DAC+Amp+i5 Headphones

DAC+Amp+i5 headphones deliver pristine audio & endless musical immersion with studio-grade precision.

Luxury Craftsmanship, Timeless Elegance

Luxurious materials meet elegant design for timeless sophistication.

Ergonomic Design, Long-Lasting Comfort

Ergonomic i5 contours to your head for secure, all-day comfort—music without distraction.

Calibrated in Pro Studio for Pure Reference Sound

Pro-tuned for pure studio sound. i5 delivers reference accuracy with planar precision.

• Immersive Listening, Pure Original Sound : Experience studio-grade audio fidelity with nano-thin diaphragm and stealth magnets. Precision acoustics deliver high-resolution, low-distortion sound for live-performance realism
• 97mm Ultra-Large Diaphragm : Industry-leading 97mm driver at 2μm thickness reveals microscopic details. Magnetron-sputtered silver alloy coating enhances clarity while ensuring long-term sonic consistency and durability
• Ergonomic Design, Long-Lasting Comfort : Memory-steel headband with multi-axis pivoting earcups adapts instantly. Silicone sliders enable micro-adjustments. Breathable protein leather ear pads eliminate fatigue during extended sessions
• Refined Craftsmanship : Handcrafted walnut wood chambers paired with CNC-milled aluminum frame. Genuine sheepskin headband and signature S-design accents exude understated luxury and timeless sophistication
• Precision Magnetic Control : 44 N50 neodymium magnets ensure razor-sharp transients. Acoustically transparent open-back grille minimizes resonance for expansive, holographic soundstage with studio-grade accuracy
  

• i5 Headphone
• 6.35mm Adaptor
• 3.5mm Cable
• User Manual