Sennheiser HDV 820 – Headphone Amplifier

Sennheiser HDV 820 – Digital Headphone Amplifier and DAC

The Sennheiser HDV 820 is a reference-grade digital headphone amplifier designed to maximize the performance of high-end audiophile headphones. It combines a high-resolution ESS SABRE32 DAC with consistently symmetrical signal processing and extremely low harmonic distortion for unadulterated music reproduction from both digital and analog sources. Designed in Germany and manufactured by a team of experts at Sennheiser's factory in Tullamore, Ireland, the HDV 820 offers versatile connectivity for virtually any source device and supports up to four dynamic headphones simultaneously.

• ESS 9028PRO SABRE DAC (32-bit/384kHz)
• DSD up to DSD256 at 12.3 MHz
• Dynamic range >115 dB at 600Ω load
• Inputs: USB (Type B), S/PDIF coaxial, S/PDIF optical, XLR, RCA
• Four outputs: XLR-3, XLR-4, dual 4.4mm balanced
• Made in Ireland
• 2 Year Warranty

Highlights & Key Technologies

ESS SABRE32 DAC & Digital Conversion
At the core of the HDV 820 is the premium ESS SABRE32 DAC (also referred to as the ESS 9028PRO SABRE), delivering a resolution of 32 bits and a sampling rate of up to 384 kHz. The converter ensures that the ultimate output is a precise match to the digital source, with fast input switching and exacting sound quality. All common word lengths and sample rates are supported. Via USB, the HDV 820 supports PCM files up to 32-bit/384 kHz as well as DSD playback up to DSD256 (12.3 MHz). The S/PDIF optical input supports PCM sample rates up to 96 kHz, while the S/PDIF coaxial input supports up to 192 kHz. An ASIO driver is included for native DSD reproduction on Windows, and Mac OS X (from version 10.6 onward) requires no additional driver installation. The DAC firmware is field-updatable via the free Sennheiser HDV 820 Updater program, available for both Windows and Mac. A dedicated DSD reproduction LED on the front panel indicates when the DAC is operating in DSD mode.

Amplifier Circuitry & Performance
The HDV 820 features symmetrical signal processing with exact signal transmission over the entire frequency spectrum. The amp circuitry provides confident gain with an exceptionally low noise floor, resulting in a dynamic range of more than 115 dB at 600 Ω load (A-weighted) and total harmonic distortion of less than 0.001%. Frequency response extends beyond the 10 Hz to 100 kHz range. Short signal paths contribute to wide bandwidth and high transient response. Maximum output power is approximately 480 mW at 1 kHz and 600 Ω load at the XLR-4 output. Gain for the unbalanced RCA input to XLR-4 output is adjustable in five steps: 14 dB, 22 dB, 30 dB, 38 dB, and 46 dB. Gain for the balanced XLR-3 input to XLR-4 output is fixed at 16 dB. The RCA input signal level can be further fine-tuned using the rear-panel input gain rotary switch.

Connectivity & Inputs/Outputs
The HDV 820 provides a comprehensive array of connections. Digital inputs include USB (Type B, minimum USB 2.0, USB Audio Class 2), S/PDIF coaxial, and S/PDIF optical. Analog inputs include balanced XLR-3 (max input level 18 dBV, input impedance 20 kΩ) and unbalanced RCA (max input level 20 dBV with minimum gain, input resistance 10 kΩ). An input selection rotary switch on the front panel allows seamless switching between all connected sources, with white LED indicators showing the active input. On the output side, four headphone sockets accommodate up to four dynamic headphones simultaneously: one unbalanced XLR-3/6.35 mm jack combo socket, one balanced XLR-4 socket, and two balanced 4.4 mm jack sockets (compatible with Pentaconn connectors). The minimum headphone impedance is 16 Ω across all outputs. A pair of balanced XLR-3 analog outputs (max output level 20 dBV, output impedance 270 Ω) passes any source along to other components such as a power amplifier or active loudspeakers, with level adjustable via the volume control. For best signal transmission with mobile HiRes audio players or smartphones, a USB OTG cable is recommended.

Design & Construction
The HDV 820 features a black anodized housing with white LED indicators on the front panel for input selection, DSD mode, and power status. The control panel provides an input selection rotary switch and a volume rotary switch. The sturdy chassis is designed for durability and long-term use. The unit should be placed on a flat, horizontal, low-vibration surface with adequate ventilation, as it generates heat dissipated through the housing. Allow at least 2 hours of acclimatization when moving from cold to warm environments. The HDV 820 is designed to complement Sennheiser's audiophile headphone range, including the HD 800 S, HD 820, and HD 660 S. It is developed in Germany and manufactured in Tullamore, Ireland.

Details & Specifications

MODEL INFORMATION
Model: HDV 820
Article number (SKU): 507442 (EU), 507443 (UK), 507444 (US), 507445 (CN), 507446 (KR)

AMPLIFIER PERFORMANCE
Frequency response: < 10 Hz to > 100 kHz
Dynamic range: > 115 dB @ 600 Ω load (A-weighted)
THD+N: < 0.001%
Max. output power: Approximately 480 mW @ 1 kHz and 600 Ω load (XLR-4 output)
Crosstalk attenuation: Min. 93 dB @ 1 kHz
Gain (UNBAL input/XLR-4 output): Adjustable — 14 dB, 22 dB, 30 dB, 38 dB, 46 dB
Gain (BAL input/XLR-4 output): 16 dB

DAC & DIGITAL INPUTS
DAC: ESS SABRE32 (32-bit, up to 384 kHz)
USB standard: Min. USB 2.0, USB Audio Class 2
USB supported formats: PCM: 32 bits; 44.1, 48, 88.2, 96, 176.4, 192, 352.8, 384 kHz / DSD: 64 (2,822,400 Hz), 128 (5,644,800 Hz), 256 (11,289,600 Hz)
S/PDIF coaxial supported sample rates: 44.1, 48, 88.2, 96, 176.4, 192 kHz (PCM)
S/PDIF optical supported sample rates: 44.1, 48, 88.2, 96 kHz (PCM)

ANALOG INPUTS
Balanced input (XLR-3): Max input level 18 dBV, input impedance 20 kΩ
Unbalanced input (RCA): Max input level 20 dBV (with minimum gain), input resistance 10 kΩ

HEADPHONE OUTPUTS
XLR-3/6.35 mm jack combo socket: Unbalanced, min. impedance 16 Ω
XLR-4 socket: Balanced, min. impedance 16 Ω
4.4 mm jack socket (×2): Balanced, min. impedance 16 Ω

ANALOG OUTPUT
Balanced output (XLR-3): Max output level 20 dBV, output impedance 270 Ω

PHYSICAL SPECIFICATIONS
Dimensions (W × H × D): Approximately 224 × 44 × 306 mm
Weight: Approximately 2.25 kg
Housing: Black anodized

POWER
Power supply: 100 – 240 V AC, 50/60 Hz
Power consumption: 12 W nominal (2 × 300 Ω headphones on 4.4 mm outputs); max 18 W (2 × 16 Ω headphones on 4.4 mm outputs)

ENVIRONMENTAL
Operating temperature: 5°C to 45°C
Storage temperature: –20°C to 70°C
Operating relative humidity: 10% to 80% (non-condensing)
Storage relative humidity: 10% to 90% (non-condensing)
Maximum operating altitude: 2,000 m (6,562 ft) above sea level

SOFTWARE & COMPATIBILITY
Mac OS X: Version 10.6 or later (no driver required; auto-recognized)
Windows: Requires HDV 820 USB Audio Software Package (WDM driver, ASIO driver, Control Panel, HDV 820 Updater)
Windows system requirements: Intel Core 2 processor 1.6 GHz (min.) or similar, 2 GB RAM (min.), Windows 7/8/8.1/10/11 (32 or 64 bit)
DAC firmware: Field-updatable via Sennheiser HDV 820 Updater (Windows and Mac)

INCLUDED ACCESSORIES
HDV 820 headphone amplifier
Power supply cable (region-dependent: EU, UK, US, CN, or KR)
Quick guide
Safety guide
Microfiber cloth