Fosi Audio Introduces the i5 Open-Back Planar Magnetic Headphone at High End 2025

The Fosi Audio i5 stands out as an open-back planar-magnetic headphone, successfully funded through a Kickstarter campaign that amassed over €200,000. Priced at approximately €350, the i5 offers a compelling combination of affordability and premium sound quality. Equipped with 97mm planar drivers and a remarkably thin 2-micrometer membrane, the i5 delivers a frequency response ranging from 10 Hz to 50 kHz. With an impedance of 28 Ohms and a sensitivity of 98 dB/mW, the headphones are recommended to be paired with amplifiers providing between 100 and 500 milliwatts of power.

Design-wise, the i5 features a sophisticated blend of materials, including plastic, walnut-finished wood elements, and metal, ensuring both durability and an appealing aesthetic. The magnetostat is engineered to avoid rigidity and fragility, contributing to the overall robustness of the build. The ergonomic design includes a memory-metal headband and bi-axial ear cup arms, allowing for seamless vertical and horizontal adjustments to fit various head shapes comfortably. Additionally, the headphones come with both 3.5mm cables and 6.35mm adapters, and the final product weighs 550 grams.

In comparison to other offerings in the market, the Fosi Audio i5 is positioned slightly higher in price than the Hifiman Deva BT by about €200, yet its design aligns more closely with the premium Sendy Audio Aiva. This places the i5 in a competitive spot for audiophiles seeking high-resolution sound without compromising on build quality or comfort.

Interested buyers have the opportunity to experience the Fosi Audio i5 firsthand at High End 2025, located in Hall 1 at Stand C03/E01. The Kickstarter campaign remains active until June 1, 2025, presenting a limited window to secure an early edition of the i5. Various packages are available, including higher-tier options with additional adapters, catering to different preferences and setups.