Final DX4000CL

Between the rigor of Japanese engineering and the ambition of a natural sound lies the DX4000CL, the second closed-back headphone in the DX series. This model takes a step up from the DX3000CL in terms of clarity and soundstage, while retaining the density that characterizes this range. Its 40 mm dynamic driver with a paper-carbon composite diaphragm is paired here with a silver-plated cable and a redesigned acoustic architecture to deliver a wider soundstage than one would expect from a closed-back headphone.

A hybrid diaphragm combining paper and carbon

The DX4000CL’s 40 mm diaphragm combines traditional paper with carbon fibers impregnated with resin, all hot-compressed to achieve a balance between lightness and structural rigidity. This combination leverages the natural damping qualities of paper and the mechanical stability of carbon. The result: precise transient reproduction, with crisp attacks and clean decays, without the artificial coloration that some synthetic materials can introduce.

The so-called “free-edge” structure allows the diaphragm to move with more controlled excursion, reducing harmonic distortion. Micro-details thus emerge effortlessly, even in dynamically complex passages.

Calibrated diffusers and acoustic chambers

Positioned just in front of the driver, the Spider-web Diffuser influences the behavior of the high frequencies. Its spiderweb-like geometry, individually tuned for this model, attenuates the interferences that usually generate treble peaks or sibilance. The highs remain present and airy, but free of harshness.

Behind the driver, diffusion bars integrated into the fiberglass shell form what Final calls the Rear Diffuser Array. This system reduces unwanted resonances inside the ear cup and contributes to a more coherent spatial rendering. Combined with an internal air pressure control system, it allows the DX4000CL to deliver an open, three-dimensional soundstage—a rare achievement for a closed-back design.

A construction designed for durability

The fiberglass-reinforced resin shell offers greater rigidity than standard ABS plastics, limiting mechanical vibrations that could color the sound. The SHIBO finish that coats it is a traditional Japanese texture inspired by the creases found in paper or leather. Beyond its understated, discreet appearance, it has the practical advantage of hiding fingerprints and resisting micro-scratches.

The earpads combine synthetic leather with memory foam. Their generous thickness ensures effective passive isolation and distributes pressure over a wide surface, making long listening sessions more comfortable, including for people who wear glasses. These earpads are replaceable, thereby extending the headphone’s lifespan.

At 375 grams on the scale (cable excluded), the DX4000CL remains within a reasonable range for a circumaural hi-fi headphone of this construction.

The silver-plated cable from the D8000 series

The DX4000CL comes with a two-meter cable whose conductors benefit from silver plating, a technology borrowed from the flagship D8000 series. This cabling aims to improve resolution and stereo imaging precision compared to standard OFC cables. The 4.4 mm balanced jack termination meets the expectations of use with audiophile-grade sources and amplifiers. A 4.4 mm to 6.3 mm adapter is included to ensure compatibility with devices featuring a standard unbalanced output.

A sound signature that is dense yet airy

The DX4000CL refines the acoustic philosophy of the DX3000CL. The signature remains balanced and natural, with generous yet disciplined bass that does not bleed into the mids. Voices and acoustic instruments benefit from a warm presence and realistic texture. The highs, filtered by the Spider-web Diffuser, retain their sparkle without ever causing fatigue over long listening sessions.

The soundstage is one of this model’s strong points. Whereas most closed-back headphones tend to project the sound in a frontal, compact way, the DX4000CL manages to create a sense of space and depth that is more reminiscent of open-back headphones. This expansive character does not, however, sacrifice the control and authority in the low end that closed-back design provides.

Power requirements and compatibility

With a sensitivity of 96 dB/mW and an impedance of 37 Ω at 1 kHz, the DX4000CL can be driven directly from a good-quality portable DAC or audiophile player. A desktop headphone amplifier will nonetheless allow you to fully exploit its capabilities, particularly bass control and dynamics on orchestral passages or recordings with high peak levels.

The passive isolation provided by the closed-back design makes this headphone suitable for use in a shared home environment or a quiet office, where it will not disturb those around you while preserving a focused listening experience.

Technical specifications

Main specifications

• Type: Closed-back dynamic headphones
• Transducer: 40 mm paper-carbon composite diaphragm
• Sensitivity: 96 dB/mW
• Impedance: 37 Ω at 1 kHz
• Weight: 375 g without cable

Design and materials

• Earpads: Synthetic leather and memory foam
  • Easily replaceable
  • Compatible with glasses
  • Effective isolation and superior comfort
• Housing: Fiberglass-reinforced resin
  • Integrated diffusion bars
  • Reduced internal resonances
  • Textured black SHIBO finish
• Cable: Premium silver-plated, 2 m
  • Included adapter: 4.4 mm → 6.3 mm
  • Inherited from the flagship D8000 series

Technologies and innovations

• 40 mm paper-carbon composite diaphragm
  • Reinforced with carbon fibers and resin
  • Hot-pressed for an optimal balance between lightness and rigidity
  • Free structure for precise transients and reduced distortion
• Spider-web Diffuser
  • Positioned in front of the transducer
  • Controls high-frequency interference
  • Individually optimized for each model
• Internal air pressure control system
  • Meticulously optimized acoustic architecture
  • Open and expansive soundstage despite closed-back design
• High-performance silver-plated cable
  • Enhanced resolution and precise stereo imaging
  • Detailed reproduction of sonic nuances
• Fiberglass-reinforced housing
  • Improved spatialization
  • Optimized natural sound
• Premium SHIBO finish
  • Delicate black texture
  • Reflects the acoustic philosophy: precision, depth, and understated elegance

Acoustic performance

• Natural and balanced sound signature
  • Powerful yet controlled bass
  • Realistic and faithful mids
  • Clear, airy treble
• Spacious and coherent soundstage
  • Details emerge without listening fatigue
  • Clear, precise, and detailed reproduction
  • No harshness
• Musical and natural character
  • Expansive sound close to open-back headphones
  • Control, isolation, and low-frequency authority typical of closed-back designs