Nagra’s HD DAC Archives

There's high-end, and there's extreme high-end, insanely priced audio gear that only the mega rich can afford. That's OK, sometimes just knowing it's out there, over the rainbow can be satisfying for audiophiles who like to dream.

Lucky me, I occasionally get to play with the world's best audio, and the Nagra HD DAC is one of those that keeps me up at night.

I dropped by the Audioarts NYC showroom to experience the HD DAC firsthand, and it definitely looked the part. Run your fingers over its exquisitely machined chassis and you know it's the real deal. Nagra started as a pro sound company with analog tape recorders that were hugely popular with film sound, radio and TV broadcast engineers in the 1950s; later on Nagra's digital machines were no less significant. Nagra introduced a line of consumer high-end gear in the late 1990s; the company designs and manufactures its products in Cheseaux-sur-Lausanne, Switzerland.

I started listening to the HD DAC ($28,310, £17,950) with high-resolution files of Miles Davis' "Kind of Blue" album. I've heard the music hundreds of times, but at Audioarts with its magnificent Zellaton Stage speakers and CH Precision A1 amplifier the music was more complete, more fully-formed and believably real than I've heard before.

As I listened I started to realize what made the HD DAC so special, it made these high-res files sound like analog tape! Bill Evans piano was closer to life size, Paul Chambers' stand up bass was more credibly realistic, and Miles Davis' horn's agility took my breath away. This 1959 album was recorded and mixed on analog tape, and with the HD DAC the "analog-ness" of the music shined through. That's never happened quite like this before, digital always sounded at least a little bit digital, here with the HD DAC there was no digital with recordings that started out as analog and carefully transferred to digital

So sure, all digital converters transform digital into analog audio, but only the HD DAC makes digital really sound like analog. I also spent some time listening to high-res files of the first Crosby, Stills & Nash album, and it had the same effect on me as "Kind of Blue" did, CSN's voices sounded palpably real, and I sensed the three men really listening to each other as they harmonized. That never happened with the digitized version of this album before, the HD DAC brought the music back to life like nothing else.

The HD DAC is also a headphone amplifier, so I brought a few of my best headphones to Audioarts to audition. First up, the Hifiman HE1000, and the clarity of the sound was astonishing. Again I played "Kind of Blue." The intimacy of the soundstage, and the sense of hearing the music direct from the microphones raised the hairs on the back of my neck! The music sounded like it was live, like it was happening right now as I listened.

I've never been all that happy with the sound of Arcade Fire's "Reflektor" album, but with the HD DAC the music's dense textures and complex reverberation were endlessly fascinating, I wished I could call all of my friends over to listen.

The sound from my high-impedance (600 Ohm) Beyerdynamic T-1 headphones was a let down, I've heard them sound better with other amps, but the T-1s are never as spectacular as the HE1000.

I also brought my Sennheiser IE 800 in-ear headphones, and their sound was transformed by the HD DAC. The scale of the presentation, dynamic range, resolution of fine detail, bass punch and power were all the best I've heard from the IE 800. I really love that headphone.

The HD DAC handles digital files with up to 384-kHz/24 bit, and DSD x 2 resolution. The connectivity suite covers all the bases: digital inputs include two RCA coaxials, two XLRs, one optical, one Nagra 12S, and one USB digital; analog outputs include a 6.3mm headphone jack, RCA and XLR stereo pairs. HD DAC is a bit smaller than most home components, it's 12.2 by 13.7 by 3 inches (277 by 350 by 76mm).

Some CNET writers are lucky enough to cover ultra-exotic cars like the 537-horsepower Aston Martin Lagonda Taraf , and that's cool, but I'm thrilled to occasionally luxuriate in the sound of ultra-high-end components like the Nagra HD DAC.

Walk this back to ‘surface’ observations. The Nagra HD DAC has excellent coherence from the deep, powerful bass to the unforced, grain-free treble. It has sublime detail and you’ll hear things in your music you didn’t know were on the recording. Vocal articulation is first rate, drawn out of a wide dynamic range, top-to-toe coherence, and an absence of background noise. The DAC is transparent, melodically, harmonically, and temporally spot on, and has the kind of flat frequency response that makes the Bonneville Salt Flats look like the Rockies. And all of that applies just as much to the powerful, servo-controlled, capacitor-free headphone socket as it does to the rest of the outputs; my HiFiMAN HE‑500s, the oBravo HAMT‑1, and even the Ultrasone Edition 5 have never sounded so right!

We are duty bound to find a downside to any product, but in concluding the review of the Nagra HD DAC, I simply couldn’t find one. It represents a leap in digital audio performance that doesn’t happen that often. It extracts a lot from existing 16‑bit, 44.1kHz files, and even shows to a high-resolution sceptic what DSD is capable of. OK, if there is a shortcoming, it’s that price tag. It’s not overpriced – if anything, once you’ve heard what the HD DAC can do, the price becomes irrelevant – it’s just that, for me, that price tag means I have to put it back in its boxes soon. And I’ll miss it greatly. Highly Recommended!

Digital inputs: 1× RCA S/PDIF, 1× BNC S/PDIF, 2× XLR AES/EBU, 1× TOSlink Optical, 1x Audio USB (mode 2), 1× I2S (Nagra format)

Signal handling: 5.6MHz/6.2MHz, 72 bits

Analogue outputs: 1× RCA stereo, 1× XLR stereo (optional balancing transformers)

Output level: 1.3 or 2V RMS (for a digital signal at 0dB FS)

Noise: –128 dBr linear (without filter)

Distortion: < 0.02% @ –20 dB FS

Harmonic Distortion: < 0.03% @ 192 kHz

Bandwidth: 5 to 40 kHz, +0/–1 dB

Signal to Noise Ratio: – 99 dB (at 1 kHz)

Dimensions (WxDxH): 280×350×76mm

Weight: 5 kg (without power supplies)

Price: £17,950 (as tested, including MPS)

Manufactured by: Audio Technology Switzerland SA

URL: www.nagraaudio.com

Distributed by: RT Services

URL: www.rtsaudio.co.uk

Tel: +44(0) 1235 810455

VFS: Vibration Free Support Plates not included as standard.

High-definition digital-to-analog converter

The HD DAC is the purist interface from the digital world to pure audio excellence. The no-compromise definition reproduces the original sound with total integrity.

Its state-of-the-art design concept, linked with high-resolution DSD features are married with the Swiss know-how from the professional domain.

Conversion

The HD DAC is designed to convert a digital signal to analogue with total integrity, without introducing the slightest impurity or colouration to the original sound. This objective has been achieved with perfection, and sound has never reached such a true level of definition.

The effort put into the design and exactitude of the Nagra HD DAC was exceptional from every perspective. Its circuits, that adopt the DSD 2X (Direct Stream Digital 128), were developed in association with Andreas Koch, the pioneering engineer of the DSD format. They run at the highest resolution available today, 128 times that of a standard CD and twice that of SACD.

Analog section

The analogue section is also the object of a superlative approach. Thanks to the quality of the signals supplied from the digital conversion circuits, the traditional steep slope filters have been totally eliminated. The consequence of this is the preservation of transients and harmonics, thus the music presents an exceptionally natural sound. Some of the critical design elements include Ultra high-performance drivers, hand-wound transformers, and a tube driven output stage.

Power supplies

There are 25 precision ultra-low-noise internal power supplies that drive the unit, giving each element its own independent and pure supply source. The Nagra HD DAC converter uses TWO stand-alone external power supplies, one for the digital section and the other for the analogue, keeping the two parts independently isolated. It can be paired up with the Nagra MPS multiple supply unit allowing it to reach its ultimate performance.

Connectivity

The HD DAC is equipped with extensive connection possibilities, allowing integration in all types of domestic and professional systems. It is particularly suited to computer environments thanks to its audio USB input, through which it receives signals up to the DSD 128 format from a PC or MAC.