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HD 820

Driver
Dynamic
Enclosure
Closed-back
Weight
360 g
List
$2,199.95
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A closed-back take on the HD 800 design with a curved Gorilla Glass cover over each driver. The glass reflects rear sound into two absorber chambers, so the ring radiator stays visible and the cup stays sealed.

Where to buy

List $2,199.95

Retailer prices checked 2026-10-21. We may earn a commission on purchases. How this works

Title block

Maker
Sennheiser
Model
HD 820
Made in
Ireland
Released
2018
Transducer
Dynamic
Enclosure
Closed-back
Driver
56 mm
Weight
360 g
Impedance
300 ohms
Sensitivity
103 dB SPL (1 V)
Frequency response
6 Hz – 48 kHz (−10 dB)
List price
$2,199.95 USD

Drive requirements

Match an amplifier in the synergy calculator
LevelPowerVoltageCurrent
100 dB1.66 mW0.71 V2.35 mA
110 dB16.6 mW2.23 V7.44 mA
120 dB166 mW7.06 V23.5 mA

Most headroom at 110 dB

Rated 97.8 dB/mW into 300 ohms. Estimated from published amplifier output.

Assembly drawing

123456

Parts

  1. 1HeadbandAdjustable metal headband, inner damping element, microfiber padding
  2. 2GrilleCurved Gorilla Glass cover over each transducer
  3. 3Ear cupClosed circumaural cups with weight-reducing composite parts
  4. 4MagnetNot published
  5. 5Diaphragm56 mm ring radiator, fixed at outer and inner edges
  6. 6EarpadsMicrofiber (2018 release: synthetic leather and microfiber)

Schematic dynamic assembly, annotated with the Sennheiser HD 820’s published materials. Not to scale.

Engineering notes

  • Curved Gorilla Glass over each transducer reflects rear sound into two absorber chambers
  • 56 mm Ring Radiator with diaphragm secured at both outer and inner edges
  • Acoustic absorber system to prevent frequency masking
  • Vibration-damping chassis and inert headband insert

Design language

Technical modernism with a window. The glass shows the transducer through the outside of the cup.

Build the listening station

Desktop sanctuary

Related architecture

Sources