Final DX4000 CL Closed-Back Headphones

A paper–carbon composite driver, 30 mm ear pads, and a silver-coated balanced cable

The final DX4000 CL brings a closed-back design to the DX series, pairing a 40 mm dynamic driver with a resin housing and a lightweight, rigid glass-reinforced resin driver front plate. Its hybrid paper–carbon diaphragm is central to the design, blending carbon with Japanese paper to increase strength while retaining low mass and high internal damping. Final describes the acoustic balance as neutral, with controlled bass and an unusually open presentation for a closed-back headphone.

Driver and Enclosure Working Together

The diaphragm uses a free-edge structure without grooves at its edge, designed to allow smooth movement and reduce distortion. Behind the driver, Final Audio's Rear Diffuser Array Structure uses ribs of different shapes and spacing to avoid parallel internal surfaces, diffuse reflected sound, and suppress unwanted enclosure resonance. These elements address the acoustic challenges of a sealed ear cup rather than relying on the driver alone.

The housing uses O-rings and precision screws, with adhesive use minimized for a serviceable construction. This approach allows the assembly to be opened for repair, an important consideration for headphones intended for long-term ownership. The hangers connecting the headband to the housings are made from lightweight, high-strength ultra-super duralumin.

Replaceable Pads and a Detachable Cable

The 30 mm thick ear pads combine a synthetic-leather exterior with a memory-foam core. They are designed to provide a comfortable acoustic seal while maintaining distance between the ears and drivers—a key part of Final’s approach to creating a more open presentation. The pads are user-replaceable without tools.

A detachable 2 m silver-coated cable terminates in a 4.4 mm balanced plug. The supplied 6.3 mm conversion adapter provides a connection to headphone equipment with a 6.3 mm output, so both connection types are covered without purchasing another cable.

Features

• 40 mm dynamic driver with a paper–carbon composite diaphragm
• Free-edge diaphragm structure and glass-reinforced resin driver front plate
• Closed-back, over-ear construction with Rear Diffuser Array Structure to control internal reflections and resonance
• Resin housing assembled with O-rings and precision screws for serviceability
• Lightweight, high-strength ultra-super duralumin hangers
• Tool-free replaceable, 30 mm thick synthetic-leather and memory-foam ear pads
• Detachable silver-coated cable with a 4.4 mm balanced termination

Included Accessories

• 2 m detachable silver-coated cable with a 4.4 mm balanced plug
• 4.4 mm-to-6.3 mm conversion adapter (sample)

Specifications

Transducer Type: Dynamic, with a paper–carbon composite diaphragm

Operating Principle: Closed-back, over-ear

Ear Cushions: Synthetic leather with memory-foam cores; 30 mm thick; user-replaceable without tools

Housing: Resin, with a glass-reinforced resin driver front plate

Cable: Detachable silver-coated cable, 2 m

Termination: 4.4 mm 5-pole balanced source plug; dual 3.5 mm 2-pole headphone connectors; 6.3 mm conversion adapter included

Driver Size: 40 mm

Sensitivity: 96 dB/mW

Nominal Impedance (1 kHz): 37 ohms

Weight (Excluding Cable): 0.83 lb. (0.375 kg)