D/A CONVERTERS

 

D/A CONVERTERS

Fewer boxes, more functionality: that seems to be the mantra of modern hi-fi. Take Marantz’s new ND8006: it’s a network player, a CD spinner, a D/A converter and a pre-amp, too. But how successfully does it juggle all those roles?

The audio industry’s quest to reduce the number of components that make up an audio system has not only resulted in the ubiquitous integrated amplifier, but various variations on the one-box-does-all theme.

For instance, a growing number of integrated amplifiers now incorporate a D/A converter with digital inputs, obviating the need for a standalone DAC. Taking it a few steps further, Naim’s Uniti components combine the functions of an integrated amp, disc player, streamer and DAC in a single, elegant box.

The Marantz ND8006 is a network player first and foremost, but adds the convenience of a CD player. To that, it adds the further benefits of an ESS Sabre-based DAC, and the ability to accept music streams via Bluetooth and Apple AirPlay. Plus, it can fulfil pre-amp duties, too.

AT FACE VALUE

Despite all that apparent complexity, it’s an elegantly handsome machine with a deceptively simply control layout that suggests ease of use. The all-metal casing features the recessed fascia and curved ‘cheeks’ that have become a Marantz hallmark.

The centrally mounted transport tray is accompanied by a large, easily legible display, while two round, multidirectional controllers on either side look after key transport and menu navigation functions.

Of note is the full-sized headphone jack, complete with adjustable level control, and a USB Type A input for flash drivers and external drives.

The rear panel provides a more obvious indication of what facilities the ND8006 offers. Firstly, there are both fixed and variable line-level outputs, confirming that the Marantz’s pre-amp capability.

The array of digital inputs spans coax, optical and USB, the latter offering both Type A for flash drives and asynchronous Type B for linking up a Windows PC or Mac. You’ll also note the Ethernet port for wired connectivity, and a pair of fold-up antennae for both 802.11 Wi-Fi, and Bluetooth and AirPlay.

The ND8006 also caters for custom installations, offering RS232, flasher and remote in/out jacks.

UNDER THE COVERS

Providing the D/A conversion capability is an ESS 9016 Sabre32 Ultra DAC, offering PCM conversions up to 384k Hz/32-bit and DSD256 compatibility (USB only). It operates in conjunction with a dual-crystal clock for reduced jitter and enhanced accuracy.

Features such as a thoroughly shielded, beefy toroidal power supply, and Marantz’s HDAM-SA2 op amps confirm a commitment to sound quality, as does the separate headphone amplifier.

From a streaming perspective, the ND8006 is uses the HEOS ecosystem to offer integrated access to services such as Spotify (now also in SA) and Tidal, as well as a full catalogue of Internet radio stations and podcasts via TuneIn.

It’s also UPnP compliant, allowing it to recognise NAS devices and the music libraries stored on them. A free HEOS app for Android and iOS makes accessing the comprehensive functions of the Marantz a simple and intuitive affair, but there’s also a conventional remote, which works with other Marantz components, such as the PM8006 integrated amp.

Let’s not forget that the ND8006 also incorporates a disc transport. While it’s sadly not SACD-compatible, it will read CDs and all CD-based recordable and re-recordable media.

SOUNDS LIKE …

The ND8006 sounded open and inviting, with a real talent for making the most of the source material it had access to, while getting out of the way of the music itself. It didn’t inject any obvious character of its own, preferring instead to ensure a clean and unencumbered pathway from source to listener.

DSD material sounded downright marvellous, regardless of whether it was being played directly from SACD, or streamed from our NAS. There was real depth and lustre to the sound, linked to a sense of transparency and accessibility.

‘Unca’s Flight’ off the Opus DSD Showcase 3 compilation, was delivered with agility and coherence, so that the close interplay between guitars and strings never became overwhelming, but invited the listener into the very heart of the performance.

The soundstage was always wide open and inviting, creating ample air and space for each instrument to come to its full right, but without losing the intimacy of the performance, nor the close interplay between the artists.

The Marantz wasn’t in the least phased by the cinematic splendour and sheer scale of the Minnesota Orchestra’s rendition of Rachmaninoff’s Symphonic Dances. It’s a taxing recording with huge dynamic swings, and presented in high-res in 176/24 WAV format, but the ND8006 always remained in effortless control, rendering the music with both power and finesse.

The player also achieved exceptional levels of transparency in partnership with both the amplifiers I tested it with, making the listening experience simultaneously exciting and engrossing, and placing the focus firmly on the music.

Macy Gray’s almost visceral performance of ‘Annabel’ (from Stripped), was presented with such impetus and conviction that singer’s presence became almost tactile. The reverb-rich electric guitar and almost percussive bass provided a suitably evocative accompaniment, while the subtle brushed snare kept perfect pace. The result was thrilling to say the least.

As mentioned, the ND8006 can access a variety of streaming services, including Deezer, Tidal and Spotify, as well as TuneIn’s vast catalogue of Internet radio stations and podcasts.

Control is via the supplied remote, or the free Helios app

The second collaboration between Ben Harper and Charlie Musslewhite, No Mercy In This Land (Tidal 44/16 FLAC) sounded powerfully persuasive, with the fuzz-edged guitar and melancholy harmonica on ‘When I Go’ a particular highlight. The delivery was emphatic and vivid, endowing the music with an almost three-dimensional presence and intensity.

Led Zeppelin’s recently remastered (and masterful) live set, How The West Was Won (Tidal 48/24 FLAC) was equally compelling: the Marantz served up Robert Plant’s piercing vocals and Jimmy Page’s expressive guitar on the classic ‘Stairway To Heaven’ with a dazzling clarity, while John Bonham’s inimitable drumwork was presented with thundering intensity.

Even compromised sources sounded pretty good: Radio Paradise delivered via Bluetooth or AirPlay from my ageing iPhone 5S had plenty musical  presence and dimension, with good tonal range and a decent stereo focus. Yes, it lacked the finesse and outright upper-treble clarity of Tidal or music-serve-based material, but it was by no means lacking in entertainment value.

Like most Marantz components, the ND8006 is available in black and champagne silver

THE BOTTOM LINE

The Marantz ND8006 is an exceptionally versatile piece of kit that offers intuitive streaming access from a wide variety of sources, together with the added convenience of CD playback, a high-res DAC, and pre-amp functionality.

The sonic approach is neutral and lucid without resorting to clinical aloofness, while focusing on offering listeners unencumbered and enjoyable access to the music instead.

The HEOS app ensures that access to the player’s extensive features set is an intuitive affair, while the pre-amp capability makes the ND8006 an ideal partner for active loudspeakers such as the KEF LS50 Wireless, to create a minimalist but full-featured set-up.

The result? A lot of functionality and musicality for the money. Indeed, the Marantz ND8006 is not a jack of all trades, but also manages to master them all convincingly.

–    DEON SCHOEMAN

PROS
A lot of features, functions and sonic talent crammed into a single, handsome enclosure.
CONS
Not everyone needs a do-it-all.

VITAL STATS

Digital conversion: ESS Sabre 9016
Digital filter: 192 kHz/32-bit
Frequency response: 2 Hz – 50 kHz (-3 dB)
Signal-to-noise ratio: 110 dB
File formats: DSD64, M4A, WAV, FLAC, WMA, MP3, AAC
Analogue outputs:
– 1x stereo RCA (fixed level), 1x stereo RCA (variable level),
– 1x 6,35mm headphone jack
Digital inputs:
– 1x SPDIF coax, 1x Toslink optical,
– 1x USB Type A (front), 1x asynchronous USB Type B (rear)
Digital outputs: 1x SPDIF coax, 1x Toslink optical
Connectivity:
– Ethernet, 802.11 Wi-Fi, Apple AirPlay,
– A2DP Bluetooth 3.0 + EDR
Compatibility:
– Up to 384 kHz/32-bit PCM and DSD256 via USB Class 2.0
– Up to 192 kHz/24-bit PCM for all digital inputs
Dimensions (WxDxH): 440 x 369 x 106 mm
Weight: 8,0 kg
PRICE
R24 990
SUPPLIED BY
HFX Systems

TESTED WITH
Marantz PM8006 integrated amplifier
Electrocompaniet PI-2D integrated amplifier
Marantz SA-KI Pearl Lite CD/SACD deck
KEF LS50 loudspeakers
KEF R500 loudspeakers
Synology DS214se NAS

SOFTWARE
Various – Opus DSD Showcase Vol 3 (Opus SACD)
Macy Grey – Stripped (Chesky 192/24 FLAC)
Rachmaninoff – Symphonic Dances – Stern/Minnesota Orchestra (Reference Recordings 176/24 WAV)
Ben Harper/Charlie Musslewhite – No Mercy In This Land (Anti 44/16 FLAC via Tidal)
Led Zeppelin – How The West Was Won – Remastered (Atlantic/Rhino 96/24 FLAC via Tidal)

One slimline box, multiple functions – that’s PS Audio’s value-added Stellar Gain Cell DAC. But can this keenly priced multitasker live up to the expectations created by more senior members of the PS Audio product line-up, including the DirectStream and DS Junior DACs?

The rise of the do-it-all integrated amp, complete with built-in DAC, network connectivity and even Wi-Fi/Bluetooth/AirPlay capability, has been threatening the very existence of more conventional, separate pre-amp/power amp combo’s in the high-end audio arena.

After all, why deal with the clutter of two or three components if they can be replaced by one box with multiple capabilities? And besides, you end up with shorter signal paths, and no need for expensive interconnects.

Whether that single box can match the fidelity and performance of individual, dedicated components remains a moot point. When you cram so much circuitry into a single chassis, concerns about interference, signal integrity and the like become inevitable.

Despite its nomenclature, the PS Audio Stellar Gain Cell DAC is a one-box device fulfilling multiple roles. It combines the functions of a pre-amp, DAC and headphone amp in a slim, elegant enclosure.

Stellar is the name of PS Audio’s most accessible product range. In addition to the Gain Cell DAC, the line-up also includes the S300 stereo power amp, and the M700 monoblock. By usual high-end standards, the Stellar gear is attractively and accessibly priced, making value-for-money a further, vital attraction.

AT FACE VALUE
Available in either black or silver, the Stellar Gain Cell DAC looks the slimline, understated part. The aesthetics border on plain, but that’s a good thing. It looks attractive in a functional kind of way, while the all-metal construction adds a reassuring robustness to the package.

The fascia is adorned with little more than the obligatory blue-illuminating PS Audio power button, a rotary volume control, a clear OLED display and a 6,35 mm headphone socket. Look closer, and you’ll see input selector and set-up menu buttons, as well as an IR receiver sensor for the included remote handset.

The rear panel provides a better indication of the DAC’s extended functionality. In its role as a fully-fledged analogue pre-amp, with a balanced circuit configuration from input to output, the Stellar offers one XLR balanced and three single-ended RCA stereo inputs, as well as a choice of XLR or RCA stereo output sets.

The partnering on-board DAC hosts  a full suite of digital inputs, including Toslink optical, RCA coaxial, and asynchronous USB Type B. The HDMI-style socket is actually an I2S input, which allows native DSD transfer from compatible disc players, such as PS Audio’s own Digital Memory Player, without DoP (DSD over PCM) conversion.

The DAC is both PCM and DSD compliant, but conversion rates and bit depths depend on the digital input.

Thus, optical is limited to PCM only at up to 96 kHz/24-bit, and coaxial to PCM at up to
192 kHz/24-bit. USB offers PCM up to 384 kHz/24-bit, and DSD64 and DSD128 via DoP, while I2S will do PCM up to 384 kHz/24-bit, and DSD64 and DSD128 natively.

UNDER THE COVERS
Two particular technologies are worth noting. The Stellar DAC’s pure-analogue pre-amp stage uses PS Audio’s Gain Cell technology for volume control. Simply put, Gain Cell varies volume by adjusting the actual pre-amplifier’s gain setting, rather than introducing separate attenuation in the signal path which could degrade signal quality and integrity.

Digital conversion is achieved via PS Audio’s proprietary Digital Lens, which consists of a simplified Field-Programmable Gate Array. Termed a Complex Programmable Logic Device (CPLD), it optimises the incoming digital signal through reclocking, wave shaping and jitter reduction.

The optimised digital data is then converted to analogue using a ESS Sabre 9010 32-bit Hyperstream DAC chip, followed by an analogue passive filter.

Talking of filters, the Stellar offers three selectable digital filter settings: slow roll-off, linear phase; fast roll-off, minimum phase; and fast roll-off, linear phase. These allow users to tailor the sound to suit personal preference, or the material being played back.

PS Audio considers the first filter setting the default, and it certainly sounds the most approachable, but to my ears, filter 2 sounded slightly more natural and open, while the third filter seemed to reveal more high-frequency detail, but also introduced a faint glare to the upper trebles.

Underlining the Stellar’s high sonic aspirations is the fully balanced Class A output stage and the presence of a large analogue transformer with seven regulators, high-speed switching diodes and 15 000 μFarad of storage capacitance.

SETTING UP
The Stellar Gain Cell DAC arrived together with a Stellar S300 stereo power amp (review pending), and I ran the duo in tandem for much of the evaluation period. However, I also partnered the Stellar DAC with our Parasound Halo A21 power amp for the sake of comparison.

It’s important to note that the Stellar gear needs a lot of run-in time – the amp more so than the DAC – so budget at least 100 hours of playing time for the DAC, and double that for the amp.

Set-up was simple, with the pre/DAC’s balanced outputs used to link it to the power amp, and our Esoteric EX-03SE universal deck roped in as the transport. I didn’t have an I2S-compatible player on hand, so coaxial SPDIF was the digital input of choice.

Linking the USB input to a headless Mac Mini allowed music files to be sourced from my NAS-based digital music library, using Audirvana 3.2.5 as the playback platform. For a purely analogue signal path, an Avid Diva II SP/SME 309/Ortofon Cadenza Black aced as source via a Sutherland 20/20 phono stage.

The set-up menu allows access to an extensive list of functions and adjustments. Every input can be renamed, balance and max volume can be adjusted, and phase inverted. A home theatre pass-through function can be activated, and the display brightness and duration adjusted.

The Stellar can also be set to DAC-only mode, which bypasses the pre-amp circuitry completely, and allows the device to operate as a standalone DAC only.

SOUNDS LIKE …
As a pre-amp, the Stellar does a sterling job of presenting its musical wares with precision and honesty. This is not a pre-amp that will spin golden tones from sonic straw, but it won’t ruthlessly punish average recordings either.

Instead, it seeks to make the most of what it’s presented with, enthusiastically rewarding quality source signals, and benignly tolerating less than ideal material. It certainly doesn’t mess with the inherent substance or character of the music, neither adding a glow to cooler tones, nor sharpening softer hues.

What it does do is provide a wide-open view of the music, affording the listener ample insight, and revealing nuances and details that less observant pre-amps might have glossed over. It also does so with a sense of contextual validity, so that you never lose sight of the music’s emotive content, regardless of the recording’s technical highlights or shortfalls.

In essence, what the Stellar serves up always sounds more like music than hi-fi – and that in itself is a remarkable achievement.

I liked its ability to reveal the full sonic picture without resorting to drama or overkill – it generally made the music sound, well, just right. Staging, scale and dynamics were truthfully represented, reflecting the character and scope of the original recording.

The pre-amp’s tonal range was certainly broad enough to accommodate anything from chilly to chilli, but the Stellar steered clear of imposing an own, specific sonic signature on the music, preferring simply to reproduce what was already there – as any decent pre-amp should.

Those characteristics appeared to remain in place when I briefly used the Stellar as a headphone amp. It was quite happy to drive the rather challenging Sennheiser HD800s, but shone brighter with lower-impedance designs such as the HiFi Man 400S and the B&W P8.

If anything, the headphones highlighted the truthfulness of the Stellar, as well as its ability to create a seamless, generous and well-balanced sound picture. Add real agility and momentum to that picture, and headphone fans should be in their element.

The Stellar’s musically satisfying performance remained consistent, regardless of source, and irrespective of digital or analogue input signal, while also easily reflecting the differences in signal quality and character.

The Cowboy Junkies’  Trinity Revisited sounded particularly haunting, with the pre-amp capturing the full impact of Margo Timmins’ tender vocals soaring above the rich but thoughtful arrangements, all encapsulated by the venue’s reverberant acoustics.

The Stellar wasn’t in the least intimidated by the density of the recording, and especially the richness of the lower registers, maintaining both clarity and composure, while also affording the music air and sonic space.

Swapping to digital material, Chris Thile and Brad Mehldau’s eponymous collaboration made for riveting listening.

The opening track, ‘The Old Shade Tree’ might sound deceptively simple, with a sparse arrangement that augments Thile’s banjo and Mehldau’s piano with a smattering of vocals, but its intimacy and natural tone presented the Stellar with a not insignificant challenge.

The recording captures the close, intuitive interaction between the two artists with such intensity that the listening experience becomes a gripping and evocative one. To the DAC’s credit, it delivered its wares with a lucid assurance that drew me right into the heart of the music.

The banjo had just the right edge and attack to sound viscerally real, while the piano provided a smooth, melodic counterpoint. The result was an intriguing juxtaposition of sound and texture, with the almost strident vocals adding to the fascination.

The Stellar did a great job of representing tonal breadth, delivering the piano’s lower registers with power and authority, while preserving the agility and zing of the banjo. It also tracked the music’s considerable dynamic shifts with precision, further benefiting the authenticity of the listening experience.

How good is the DAC section? Well that depends on your personal benchmark. Sonically, it’s adept and wholesome, painting the music with confident strokes, and using its bountiful harvest of detail to create a full, panoramic music picture.

It’s generous in the staging department, too, but compared to the (much more expensive) DirectStream DAC, the sound picture isn’t as holographic, and the  imaging not quite as finely focussed.

The DirectStream delivers its wares with greater urge and foundation, too – but given how much affordable the Stellar is (and the fact that you get a full-fledged pre-amp as part of the deal), the value proposition is impressive to say the least.

THE BOTTOM LINE
The PS Audio Stellar Gain Cell DAC proves that high-end can be had for less than you think. Combining pre-amp and DAC (plus that headphone amp) makes practical sense, while ensuring exceptional versatility.

But it’s this pre/DAC’s engaging musicality, together with real bang for the buck, that sets it apart. Indeed, it may just be the keenest weapon in PS Audio’s already impressive product arsenal. Now, how about a dedicated, no-frills, fully balanced Stellar pre-amp?

VITAL STATS
Digital conversion: CPLD (Complex Programmable Logic Device),     ESS Sabre, 32-bit
Formats: PCM, DSD, input-dependent
Frequency response: 20 Hz – 20 kHz (+0, -0,25 dB)
Signal-to-noise ratio: >110 dB (1 kHz, max output)
Digital inputs: 1x I2S, 2x coaxial RCA, 1x Toslink optical, 1x asynchronous USB
Analogue inputs: 1x stereo XLR, 3x stereo RCA
Outputs: 1x stereo XLR, 1x stereo RCA, 1x 6,7 mm headphone socket
Dimensions (WxDxH): 432 x 305 x 76 mm
Weight: 6,12 kg
Price: R22 100
VERDICT
Analogue meets digital in this innovative pre-amp/DAC with headphone facilities, too. Sonically, the Stellar always exceeds expectations, with finesse and believability its stand-out traits.
SUPPLIED BY
PL Computers. 082 578 5708
WEBSITE
www.psaudio.com

ASSOCIATED EQUIPMENT
Esoteric Audio EX-03SE universal player
PS Audio DirectStream DAC
Avid Diva II SP/SME 309/Ortofon Cadenza Black
Sutherland 20/20 phono stage
Naim Uniti2 one-box system
Parasound Halo A21 power amp
Vivid Audio V1.5 loudspeakers
PS Audio P5 power regenerator
TelluriumQ Black interlinks and speaker cables
Synology DS213+ NAS
Mac Mini/Intel Core i5, 2,5 GHz, 10 GB RAM, 500 Gb HDD

MUSIC
Chris Thile/Brad Mehldau – Chris Thile and Brad Mehldau (Nonesuch)
Javier Limon – Mujeres De Aqua (Universal)
Billy Gibbons – Perfectamundo (Concord)
Mozart – Requiem – Dunedin Consort (Linn Records 192/24 FLAC)
Boston – Boston (Sony/BMG DSD64)
Fry Street Quartet – Beethoven String Quartets (Own Label SACD)
Cowboy Junkies – Trinity Revisited (Diverse Records LP)