When working at home or in the studio, you need your mix to sound as it does when your listeners hear it. The HD 400 PRO open-back studio headphones provide a natural and accurate listening experience for fine tuning your signature sound. Its lightweight design and velour earpads provide the comfort you need during long sessions. In addition, open ear cups and angled transducers allow for a wide and transparent soundstage, making the HD 400 PRO a reliable companion for those who put quality and precision above all else.
It’s all in the mix. When working at home or in the studio, you need your mix to sound as it does when your listeners hear it. The HD 400 PRO reference headphones are your everyday tool to get the job done. Its open-back design provides a natural and accurate listening experience for fine tuning your signature sound. The core of the HD 400 PRO is the 120-ohm transducer developed by Sennheiser engineers, featuring a specialized polymer blend in its diaphragm. The highly efficient driver magnet provides clarity while its damping system manages ventilation. This results in deeper bass while extenuating distortion that otherwise impacts sound quality — a difference our professional users will appreciate. This makes the HD 400 PRO a precise monitoring tool which reveals your mix in every detail. Velour earpads and a distinct lightweight design provide the comfort you need during long sessions. The robust housing endures everyday wear and tear regardless of your application, whether editing, mixing or mastering. A single-sided and coiled cable gives you the freedom to operate. For convenience, a straight cable is also included in the delivery. In addition, open ear cups and angled transducers allow for a wide and transparent soundstage, recreating the optimal listening position found in high-end recording studios. Artifacts of a confined space are a thing of the past. The HD 400 PRO is a truly reliable companion for those who put quality and precision above all else.
Reference-grade headphones for project and professional mixing sessions The frequency range of HD 400 PRO was developed to be honest across the board, especially when it comes to the lower end of the spectrum. The angled transducer design allows for unique stereo imaging, reproducing the spatial sound of your mix. In other words, what goes in is what comes out. Reproducing analytical audio, the HD 400 PRO reference headphones are your everyday tool to get the job done.
Open back, open mix Open ear cups allow for a wide and transparent soundstage, recreating the optimal listening position found in high-end recording studios. Artifacts of a confined space are a thing of the past. These studio headphones do not construe, but rather ensure neutral transparency – the groundwork for the best mixes.
The perfect synergy of comfort & precision Let's face it, mixing sessions are never quick. The HD 400 PRO's lightweight design allows you to focus on your project for hours on end. Articulating earcups, velour earpads and an adjustable headband allow for adaptability and comfort to perfectly match the shape of your head. Our self-developed 120-ohm transducers are tuned for accuracy to deliver every detail of your mix. The highly efficient driver magnet provides clarity while its damping system manages ventilation. This results in deeper bass while extenuating distortion that otherwise impacts sound quality — a difference professional users will appreciate.
More tools for more options The HD 400 PRO features a detachable coiled cable. For convenience, a straight cable is also included in the delivery. With a screw-on adapter you can connect to your mixing desk, audio interface or any audio device that has a 1/4-inch (6.3mm) or 1/8-inch (3.5mm) output.
First Pro dedicated open-back headphones for professional mixing, editing and mastering
A professional’s tool with neutral sound reproduction
Lightweight design for all-day usage
Single-sided, coiled cable allows freedom to operate. Straight cable included as well for more compact applications
Angled transducers designed for low distortion at high SPL provide a spacious and accurate soundstage
Ear pad material
3.5 mm jack plug with
6.3 mm adapter
6 Hz to 38 kHz (-10 dB)
Sound pressure level (SPL)
110 dB (1 kHz / 1 V RMS)
THD, total harmonic distortion
< 0.05 % (1 kHz / 90 dB SPL)
Weight (w/o cable)
Operation: –15 °C to +55 °C (5 °F to 131 °F)
Storage: –55 °C to +70 °C (–67 °F to 158 °F)
≤ 90 %
HD 400 PRO Studio Reference Headphone
3 m coiled cable with 3.5 mm jack plug
3.5 mm jack plug to 6.3 mm adapter
1.8 m straight cable
Sennheiser Warranty (except USA, Australia, Brasil)
The original Sennheiser product you have purchased is covered by a warranty of 24 months. For some products a different warranty period applies. For the exact duration of your warranty, please refer to the separate extended warranty table. The limited warranty applies only to products that belong to the time of purchase to the current Sennheiser sales program. The warranty period begins on the date of purchase of brand new, unused products by the first end user. Please retain your sales receipt (or your warranty certificate) as proof of purchase. Unless you submit proof of purchase, which will be verified by your local Sennheiser service partner, you will be obliged to pay for any repairs that are carried out. Proof of purchase must state the date of purchase and name of the product.
If, within the warranty period, the product is determined to be defective (at the date of original purchase) due to improper materials or workmanship, Sennheiser electronic GmbH & Co. KG or their service partners will, without charge for labour or parts, repair or (at the descretion of Sennheiser electronic GmbH & Co. KG) replace the product or its defective parts.
Sennheiser electronic GmbH & Co. KG or their service partners may replace defective products or parts with new or refurbished products or parts. All products and parts replaced become the property of Sennheiser electronic GmbH & Co. KG or their service partners.
The following cases are not covered by the above warranty:
Minor faults or deviations in the quality of a product which do not affect the product’s value or fitness for its intended purpose
Any accessories supplied with the product
Rechargeable and disposable batteries (these products have a shorter service life, the length of which also depends on the frequency of use)
Faults resulting from improper use (e.g. operating errors, mechanical damage, incorrect operating voltage) Proper use for the purposes of this warranty is defined as use of the product under the conditions stated in the instructions for use.
Faults due to wear and tear
Any modification of Sennheiser products effected by you or a third party, unless Sennheiser has given its prior written consent to the nature and extent of the modification
Faults due to force majeure
Faults of which the purchaser was already aware at the time of purchase
All warranty claims become void if the product is tampered with by unauthorised persons or repair shops. Further, this warranty is voided by removal or alteration of identification labels, serial numbers or safety labels on the product or its parts. Warranty claims can be enforced in any country throughout the world in which the statutory rights of the country concerned are not in conflict with our warranty regulations. No other warranty claims or claims over and above the rights stated in these terms and conditions will be accepted.
Consumers may be entitled to statutory rights in their own countries which are not restricted by these warranty terms and conditions, as the warranty is governed by the laws of the country in which the Sennheiser product was purchased by the consumer. The provisions of the UN Convention on the International Sale of Goods do not apply to this service.
If you wish to file a claim under the warranty, please contact your local service partner for detailed return instructions. An up-to-date list of all service partners of Sennheiser electronic GmbH & Co. KG worldwide is available on the internet at Service Partners Worldwide.