Sennheiser HD 400 PRO Open-Back Studio Reference Headphones

Acoustic Transparency & Spatial Precision: Sennheiser HD 400 PRO

The Sennheiser HD 400 PRO open-back circumaural headphones are designed as an indispensable everyday tool for sound engineers, music producers, and content creators working in home or professional recording studios.

Engineered for linear, uncolored sound reproduction, the HD 400 PRO features specially developed polymer-blend diaphragms and angled transducers that accurately recreate the sweet-spot acoustic environment of physical studio reference monitors. Available now in our Sennheiser pro audio catalog, the HD 400 PRO provides unmatched soundstage clarity, revealing subtle micro-details, vocal balance, and spatial depth across your entire mix spectrum.

Key Features & Pro-Level Advantages

• Open-Back Acoustic Design: Delivers a wide, spacious stereo soundstage with natural acoustic airiness, ideal for critical mixing and mastering decisions.
• Angled Driver Architecture: Transducers are angled to replicate the optimal listening position of stereo monitor speakers inside a treated control room.
• Ultra-Wide Frequency Range (6 Hz – 38,000 Hz): Captures sub-bass extension down to 6 Hz alongside crystalline high-frequency detail far beyond the range of human hearing.
• 120-Ohm High-Power Transducers: Polymer-blend diaphragm and high-power magnet system manage airflow to yield deep bass while eliminating non-linear distortion.
• Supreme All-Day Velour Comfort: Lightweight housing (240 g) combined with soft, breathable velour ear cushions ensures cool, pressure-free listening during marathon editing sessions.
• Dual Interchangeable Cable Options: Includes a 3 m coiled cable for console mobility and a 1.8 m straight cable for compact workstation setups.

Key Technical Specifications

• Device Type: Professional Over-Ear (Circumaural) Open-Back Reference Headphones

• Transducer Principle: Dynamic, Open-Back

• Transducer Positioning: Angled Drivers (mimics nearfield studio monitor alignment)

• Frequency Response: 6 Hz – 38,000 Hz (-10 dB)

• Nominal Impedance: 120 Ohms

• Sound Pressure Level (SPL): 110 dB SPL (1 kHz / 1 Vrms)

• Total Harmonic Distortion (THD): < 0.05% (1 kHz / 90 dB SPL)

• Ear Cushion Material: Soft Breathable Velour

• Cable Routing: Single-Sided Detachable (Locking Braid Mechanism)

• Cable Types Included: 3.0 m Coiled Cable + 1.8 m Straight Cable

• Connector: 3.5 mm (1/8″) Gold-Plated Jack with Screw-On 6.3 mm (1/4″) Adapter

• Weight (w/o cable): Approx. 240 g (8.4 oz)

• Color: Matte Black

Compatibility & System Integration

• Studio Hardware Integration: Optimized for dedicated audio interfaces, headphone amps, mixing consoles, mastering suites, and spatial audio software (e.g., Dear Reality dearVR MIX).

• Replacement Parts: User-replaceable velour ear pads, headband cushions, replacement coiled cables, and straight 1.8 m replacement leads.

• Box Contents: 1x Sennheiser HD 400 PRO headphones, 1x 3 m coiled cable, 1x 1.8 m straight cable, 1x 3.5 mm to 6.3 mm (1/4″) screw-on adapter plug, quick start guide.

• System Expansion: Complete your studio setup with matching Sennheiser MK 4 / MK 8 condenser microphones and wireless monitor systems on our Sennheiser Brand Store.