Sennheiser HDV 820

The front panel offers a large volume control, a white-rimmed illuminated power switch, a five-way source selector with white status LEDs and a total of four headphone outputs: one combo jack for XLR and 6.3 mm plugs, one XLR-4 jack and two 4.4 mm Pentaconn jacks – the latter of which are designed for balanced operation in which the required signal is transmitted in antiphase over two wires. This reduces the sensitivity to external interference and allows higher volume levels.

In addition to an expressly high-quality analogue section, which unlike the Orpheus HE 1’s headphone amplifier relies on a purely transistorised circuit, the HDV 820 also offers a top-class D/A converter with a USB 2.0 computer connection. With a price tag of 2,399 Euros, it is therefore priced higher than the now discontinued, purely analogue model HDVA 600.

For the signal, you can choose between analogue unbalanced (Cinch), balanced (XLR) and the digital sources USB 2.0, S/PDIF optical and S/PDIF coaxial. On the digital side, the ESS-SABRE32 D/A converter is used, this offers resolutions up to 32 bits, sampling frequencies up to 384 kHz and bitstream up to DSD256 (12.3 MHz). If a bitstream format is detected, the corresponding status LED lights up on the front.

For the unbalanced input, there is a level controller on the back that has to be set with a screwdriver and allows fine adjustment. As with the HDVA 600, there are XLR outputs as a special feature, turning the unit we tested into a true preamplifier that can also feed active monitors or power amps.

In practice

Besides source selection and level control, there is nothing to adjust on the HDV 820. So conceptually, it’s all about pure music enjoyment. Accordingly, I didn’t miss having a level or resolution display on the unit. On the other hand, I would have been happier if there were a remote control.

I consider the balanced XLR outputs to be a worthwhile added value, as the HDV 820 can thus take on the role of a preamplifier and central D/A converter. This was just as useful for a listening room as it was in a professional environment, for example, if you want to work alternately with headphones or loudspeakers at a workstation. However, I found the hard-coupled volume control for this output impractical. At the very least, I would have liked to see a mute button for the XLR output.

The USB connection is made via macOS with Class Compliant drivers, while the Windows drivers are supplied on a USB stick. The HDV 820 can be connected via a system driver or the professional ASIO protocol from a studio software. Firmware updates can also be installed on the unit via USB.

The maximum output power depends on the output jack used and the resistance of your headphones. It is about 480 mW at 600 Ω load at the XLR-4 output. But don’t worry: the level reserves are completely sufficient even with quieter headphones. In addition, there is the option of balanced operation, which again significantly increases the output level.

Sound

Like any good amplifier, the HDV 820’s job is to deliver the source to the listener at the desired volume in an unadulterated, accurate and fully controlled manner. The test unit did exactly that, with exemplary low noise. It actually sounded good at any volume. In fact, it sounded so good that even higher levels could be enjoyed without distortion and the volume control could quickly be turned up too high – a phenomenon associated with high-quality component combinations.

In principle, of course, the HDV 820 works with almost any wired headphones, but according to the manufacturer, it is optimised for headphones with high impedances. The real added value of such a design particularly reveals itself in combination with the most high-quality headphones – for the purpose of a continuous audiophile playback chain, which was virtually self-evident, even given the price.

In combination with the HD 800 S and HD 820, the amplifier provides sufficient level reserves and otherwise performs exactly as one would expect from such a great reproduction chain. High-resolution and without embellishment, the HDV 820 offers a glimpse into the quality of each mix/sound source and its character in terms of level ratios, frequency tuning, dynamics as well as stereo positioning and space.

In its basic tone, this Sennheiser product is fast and tuned rather analytically. It deliberately does not bring any fundamental warmth into the reproduction and is in no way loud in the bass, but always controlled. At the other end of the frequency scale, the amplifier is linear far beyond the listening range and correspondingly open and airy.

At the same time, it reproduced the multi-layered mixes of Steven Wilson’s latest CD (The Future Bites) in an impressive manner. Fine details, three-dimensionality and precision go hand in hand with a complete frequency response and perfectly comprehensible dynamics. In addition to a meticulously constructed stereo panorama, the HDV 820 can also convey a remarkable closeness. In fact, you feel like you’re sitting in the recording room with Tina Dico as she performs “The Woman Downstairs”.

Whether modern metal music, orchestral works, intimate singer/songwriter compositions or bass rumblings from the dancehall genre – the HDV 820 always remains calm but extremely attentive. With this amplifier, differences between headphones quickly become just as apparent as differences between mixes. Indeed, one almost automatically approaches the sound assessment a good deal more critically. Sometimes it sounds a little too slender or slightly too bright, then pleasantly warm and round or even boomy. The only difference is that in the bass the results never right upon your face – provided you have a good mix. These are all qualities that sound professionals appreciate. Supplied with balanced or digital signals, here you have an exquisite alternative monitor for mixing, editing or genuine premium listening quality from professional speakers. By the way, balanced operation is not necessarily sonically superior, it just delivers more level.