FiiO JT7 Open-Back Planar Magnetic Headphones

FiiO JT7 Open-Back Planar Magnetic Headphones

• Open-back over-ear headphones built around a high-performance planar magnetic driver

• Large 95×86 mm planar unit

• Ultra-thin 3-micron diaphragm

• F.E.S. “Elastic System” for enhanced responsiveness

• Dual high-density heterogeneous magnet array

• Lightweight and foldable structure

• Ergonomic headband with four-axis rotation

• Replaceable earpads and headband cushion

• Ships with both 3.5 mm and 4.4 mm cables

• Hi-Res Audio certification

Technical Specs

• Impedance: 18 Ω at 1 kHz

• Sensitivity: 92 dB/mW at 1 kHz; 109 dB/Vrms at 1 kHz

• Frequency response: 7 Hz–40 kHz

• Headphone connectors: Dual 3.5 mm

• Cable terminations: 3.5 mm / 4.4 mm

• Weight: approx. 318 g

The FiiO JT7 is a newly developed open-back planar magnetic headphone designed for listeners who want a detailed, energetic sound paired with long-wear comfort. At its core is a proprietary 95×86 mm planar driver built around an ultra-slim 3 µm diaphragm. The unit incorporates FiiO’s in-house F.E.S. (FiiO Elastic System), a structural approach that improves elasticity and transient response, strengthens bass performance, and keeps distortion extremely low.

A set of high-density neodymium magnets arranged in a two-sided configuration provides strong magnetic force and contributes to the JT7’s high sensitivity. Through precision engineering, FiiO uses a chip-grade 28 nm manufacturing process to bond the diaphragm and voice coil into a unified component, improving both accuracy and long-term durability. The result is a headphone tuned for clean, high-fidelity sound without pushing the price into the stratosphere.

Self-Developed Large Planar Driver

FiiO designed the JT7’s 95×86 mm planar driver entirely in-house, optimizing each part—diaphragm, voice coil, and magnetic circuit—for consistent, high-quality performance. The extremely light 3 µm diaphragm enables quick, controlled movement across the entire frequency range, helping the headphone deliver a clear and spacious presentation.

Rich, Dynamic Low-End with F.E.S.

The F.E.S. structure adds patterned textures to the diaphragm surface, functioning somewhat like the surround of a dynamic driver. This approach increases elasticity and improves control of internal tension, letting the diaphragm move more freely and quickly. Compared with conventional planar designs, the JT7 produces deeper, punchier bass with reduced distortion.

Precision Manufacturing

Using a 28 nm chip-grade process, FiiO seamlessly integrates the voice coil and diaphragm into a single ultra-precise module. This method results in extremely fine coil traces and a more stable, longer-lasting driver assembly.

Enhanced Magnetic Field Structure

The JT7 employs a two-way arrangement of heterogeneous high-density magnets that generate a powerful magnetic field. This allows the driver to achieve high output levels with ease, meaning the headphone can perform well even when driven by modest portable sources. A high-sensitivity, low-distortion design makes the JT7 friendly to a wide range of playback equipment.

Lightweight and Foldable

Weighing around 318 grams, the JT7 maintains a light and comfortable wear profile. The headband rotates across four axes to help users dial in an ideal fit, and the entire frame folds for easier transport. Both the earpads and headband cushion can be swapped to suit personal preferences.

Detachable Cables with Two Options Included

The headphone uses dual 3.5 mm jacks for cable connections. FiiO includes two stock cables—one single-ended with a 3.5 mm plug, and one balanced with a 4.4 mm termination. A 3.5 mm to 6.35 mm adapter is also provided for compatibility with desktop equipment.

Driver Configuration

95×86 mm planar driver

3 µm PET diaphragm with silver-plated aluminum-alloy voice coil

Frequency Response

7 Hz–40 kHz

Sensitivity

92 dB/mW @ 1 kHz

109 dB/Vrms @ 1 kHz

Impedance

18 Ω @ 1 kHz

Headphone Connector

Dual 3.5 mm (TS)

Cables

Dual 3.5 mm (TS) → 3.5 mm single-ended

Dual 3.5 mm (TS) → 4.4 mm balanced

Accessories

Headphones

Cloth pouch

3.5 mm cable

4.4 mm balanced cable

3.5 → 6.35 mm adapter

Quick-start guide