Features

• The new standard for closed audiophile headphones
• Concave Gorilla Glass reflectors offer sound reproduction with an incredible sense of space
• Ultra-ergonomic adjustable metal headband with internal cushioning element
• Developed in Germany and precisely manufactured at Sennheiser's state-of-the-art facility in Ireland
• Frequency response: 6 - 48,000 Hz (-10 dB)
• Dynamic transducer system with 56 mm ring radiator
• The acoustic absorption system prevents frequency masking for unexpected details
• Microfiber padding for ears and headband extremely comfortable at key contact points
• Impedance: 300 ohms
• Total harmonic distortion: 0.02 % (1 kHz 1 Vrms)

Completely closed. Incredibly open.

The HD 820 headphones combine our cutting-edge transducer capabilities with exceptional ambient noise attenuation, surpassing the perceived limits of closed headphones.

Until today, the audiophile headphone experience could only begin with Sennheiser's open design, which paved the way for an entire category of precision listening devices. This standard of sound reproduction would surpass exponentially larger and more expensive hi-fi systems, with the understanding that listeners would not be isolated from their surroundings. The HD 820 headphones sacrifice neither details nor soundstage, thanks to their innovative acoustic systems in a closed, dynamic headphone.

Internal Reflection

A closed headphone capable of producing the wide and natural soundstage of an open headphone requires rethinking the directional characteristics of sound waves.

Although sealed headphones offer maximum privacy, redirected energy can create resonance and distortion within the ear. The inimitable experience of the HD 820 comes from the use of precision concave glass reflectors, one for each ear cup. Located on the outer plane of each ring radiator transducer, these plates reflect the energy from the back of the speaker towards a specially tuned absorption system, allowing the waves to mimic the behavior shown in open models like the HD 800S. In addition to being a visually striking feature, the technical execution of the glass reflector offers a sound spectrum never before experienced in a sealed headphone.

The Fellowship of the Ring

A truly remarkable aspect is that the 56 mm ring radiator of the HD 820 takes advantage of a crucial transducer with a large diaphragm, that is, air distribution, without losing the rigidity that positively affects rest and response times.

There is no single fastening element on the outer circumference of the transducer, but both the outer and inner edges of the ring are fixed to the driver unit. The voice coil vibrates the diaphragm, connected to the V-shaped groove near the center of the ring. The anti-vibration frame of the headphones and the inert headband insert ensure total stability, with surprising speed and precision across the entire frequency spectrum. Exactly what goes in comes out of the HD 820. Each transducer is produced, tested, and measured with extremely rigorous tolerance, to ensure the most reliable performance right from the start. Each HD 820 model also includes a frequency response diagram specific to the serial number of that set; no resources are spared to help you recover the most critical details from every corner of your music collection.

High Precision Engineering

The deep and almost magical stereo sound of the HD 820 reflects all the meticulous design that has gone into it.

Developed in Germany and built in our state-of-the-art factory in Ireland, its design and finishes are second only to sound quality. Thanks to the extraordinary response of the ring radiator and the adjustment of the angle of the speakers, it is easy to find the right sound, the right instruments, and the right environment. The soundstage skillfully balances realism and esotericism, transporting you directly to the heart of your favorite recordings. The luxurious ear pads and progressive articulation points ensure sufficient isolation, eliminating distractions and allowing you to focus best during long listening sessions. Whether for critical listening or private conversations, the HD 820 prevents unwanted sounds from entering or exiting.

An Ergonomic Pleasure

The HD 820 also offers long-term comfort, ensuring a listening experience as soft as it is engaging.

Each contact point features very soft padding, while specially designed materials reduce weight and unwanted pressure. Each ear cup features a dual-axis hinge that adapts instantly and effortlessly to the shape of your head. The result is a listening session that does not hinder your passion for high-fidelity sound reproduction in any way.

It's All About Relationships

As a central element of an ever-evolving system, your reference headphones must guarantee the versatility necessary for listening in line with your needs.

The HD 820 comes with a versatile set of essential cables, each with an impedance matched to extra-low capacity. The 6.3 mm (¼ inch) stereo connector is the audiophile standard for connecting to devices such as headphone amplifiers, DACs, and A/V receivers. The 4.4 mm balanced connector paves the way for a new generation of balanced output devices (headphone amplifiers, digital audio players, etc.) that take advantage of the stability of this compact connector that proves superior over time. An optional XLR-4 balanced cable is available, offering further connection to a wide range of audio components. Each cable is 3 meters (9.8 feet) long to allow for free listening to devices located anywhere in your studio, on the shelf, or on the desk.