dCS Network Bridge: Crossing digital waters

Streaming is the new audio buzzword – but how do you add streaming capability to an existing system without reinventing the wheel? The dCS Network Bridge is an attractive and sonically revealing solution

By Deon Schoeman

Navigating the often stormy digital waters of an audio system can be a treacherous affair. Over and above the PCM vs. DSD debate, there are file formats such as WAV, FLAC, AIFF and more to consider, together with the different sampling rates and bit depths on offer.

Lately the question of physical media versus digital libraries has become increasingly relevant as music lovers and audio fans realise the convenience of streaming digital content from a local server (or streaming service) to their system.

Add content management software such as Roon to that equation, and it becomes both intuitive and enjoyable to explore both new and existing content, often stumbling across long forgotten albums and artists in the process.

An essential element of the streaming process is how to actually access and play the digital content you have stored on a laptop, computer or network. An increasing number of universal transports, AV receivers, integrated amplifiers and pre-amplifiers offer network connectivity and UPnP capability, which allows them to identify and access storage devices containing digital content.

However, in the high-end stereo context, a standalone streamer that creates a dedicated link between the stored digital content and a digital-to-analogue converter, is the preferred route to follow. The dCS Network Bridge is just such a device.

It stands to reason that the Network Bridge was conceived primarily to serve the needs of existing dCS DAC owners. The British brand’s high-end D/A converters have an established reputation for sonic excellence, and owners seeking a streaming solution will demand similar levels of technical and sonic integrity.

Thus, in the first instance, the dCS Network Bridge has been designed to operate in conjunction with both legacy and current dCS DACs. For that reason, it also offers both word clock connectivity and SDIF-2 (which separates clocking and music data) compatibility.

Of course, that doesn’t preclude the Network Bridge from being used with DACs from other brands, while benefiting from the fastidious design and technical prowess dCS has become known for.

AT FACE VALUE

The dCS Network Bridge is a minimalist, all-alloy component that’s slightly smaller than normal DIN-sized components. The front panel is devoid of any switchgear, and is populated by a sole, blue LED indicator to confirm power on status.

The rear is populated by an all-digital output array comprising a pair of AES/EBU outputs, a SPDIF output over RCA, and a pair of SDIF-2 outputs over BNC. Two more BNC connectors allow the Network Bridge to be linked to a dedicated word clock device for reduced jitter.

There’s also a USB Type A input for convenient connection of a USB hard drive or flash drive, and the dCS is even compatible, with Apple AirPlay. Network connectivity is provided via an RJ45 Ethernet jack or 802.11 Wi-Fi, but using the latter imposes a 96 kHz/24-bit limit, so a hardwired network connection is very much the preferred option.

The two AES/EBU outputs can be used individually, or combined in Dual AES configuration (as catered for by some dCS DACs). Individually, output is limited to 192 kHz/24-bit PCM and DSD64 in DoP format, but in Dual AES mode, this increases to 384 kHz in PCM, and DSD64/128.

The dual-BNC SDIF-2 interface does PCM at up to 96 kHz/24-bit and DSD64, while the single SPDIF over RCA digital output delivers up to 192 kHz and DSD64.

To ensure compatibility with older DACs that may not support higher resolution data, downsampling is also offered all the way down to 96/24 or 88,2/24 depending on the resolution of the source file. Similarly, DSD can also be downsampled to either 176,4 kHz or 88,2/ kHz at 24 bits.

Key to operating the Network Bridge is the dCS app, which offers intuitive control of the device itself (including firmware updates and clock settings), but also acts as the interface between the bridge and its data sources, including two integrated streaming services – Tidal, and Spotify Connect.

Since the Network Bridge is a UPnP renderer, it will identify any UPnP-compatible storage device available on the network it’s linked to. It will index the content on that device and allow searches based on folder, artist or album, as well as displaying artwork where available.

The good news for Roon users is that the software management programme recognises the Network Bridge as a Roon endpoint. And the latest firmware update, released in May, also allows the dCS to do a first-stage unfold of MQA-encoded files, upping the standard 44,1 kHz resolution to 88,2 or 96 kHz.

UNDER THE COVERS

The dCS Network Bridge uses a field programmable gate array (FPGA) platform which performs all the upsampling and downsampling, as well as auto-reclocking incoming digital data.

As with all dCS products, meticulous power regulation, including isolating digital and clocking circuitry is a feature of the Network Bridge.

The FPGA-based architecture also allows for future-proofing via firmware updates containing new features or improvements, as witnessed by the addition of MQA first unfold capability via a recent firmware update.

SETTING UP

The Network Bridge was hooked up to my dedicated listening room network via Ethernet and a gigabyte switch. My PS Audio DirectStream DAC, fitted with Bridge II, was on DAC duty, and was linked to the dCS via single AES/EBU.
I loaded the dCS app onto my ageing iPhone 5S running iOS 11.4 from the Apple App Store. Once installed, it instantly saw the Network Bridge (which was brand new), which had already recognised and connected to my network.

The app determined that new firmware was available, and proceeded to download and install the latest version. Thereafter, it also recognised the Synology NAS on my system and was able to display the around 2 000 albums on the server.

Once I’d provided my subscriber credentials, Tidal also became available as a source, while Spotify Connect used the existing access info on my iPhone to add it to the source choice list.

I used Roon with all upsampling and DSP functionality disabled as the primary interface while using the Network Bridge, as it remains one of the most intuitive, and neatly integrates NAS-based and Tidal content.

It also allowed convenient, direct comparisons between the dCS, and the bespoke Conversdigital-supplied Bridge II network card installed in the DirectStream.

However, I also used the dCS app on its own to source and play back content, and to control the operating parameters of the Network Bridge.

The remainder of the system comprised a Mark Levinson No.26 pre-amp (review pending), PS Audio M700 monoblocks, and a pair of Vivid Audio V1.5 loudspeakers.

SOUNDS LIKE …

The dCS Network Bridge contributed to a very spacious, airy and accessible sound that brought greater focus and clarity to the music. Particularly prevalent was the heightened dimensionality and presence of the delivery, allowing both enhanced insight and greater engagement.

Also notable was the precision of the delivery, at both macro and micro detail levels. There was a sense of greater realism and believability, driven by the ability to making each instrument and each voice sound more plausible, without losing sight of the overall cohesion of the performance.

The dCS didn’t enforce a dispassionate analysis of the music, but rather afforded the listener a closer connection with and a deeper understanding of the material.

The deceptively simple, blues-tinged ‘Boogie Stupid’ from John Scofield’s Überjam Deux is always entertaining in a foot-tapping kind of way, but the dCS brought a more pervasive sense of scale and dimension to the music.

Scofield’s brilliant guitar still sounded commanding, but it was better spatially defined on a more expansive, more accessible soundstage that also afforded the other instruments greater scope and thus more prominence.

That was as true of the rhythm guitar on the right channel as it was of the incisively executed drumwork, and the almost squawky keyboard on the left.

Despite opening up the soundstage and bringing more definition and precision to the overall performance, there was nothing clinical nor surgical about the way the dCS opened up the music. Instead, it was a case of the Bridge being able to deliver improved focus and enhanced clarity – like polishing the lenses of a pair of spectacles that have become slightly tarnished.

Compared to the dCS, the DS Bridge II sounded a little more constrained and conservative, with a soundstage that couldn’t match the dCS for depth and ambience. The sound was tidy and linear, with fine pace and clean detail, but there was not as much spatial splendour: the music had greater presence and substance under the dCS’ care.

That same sense of atmospherics, of soundstage depth and authentic ambience, was prevalent when listening to Ry Cooder’s The Prodigal Son.

On ‘Straight Street’, Cooder’s almost plaintive vocals are set against a rich backdrop of a male chorus, precisely detailed percussion, and expressive banjo and guitars. The song starts simply, then gradually adds tonal hues and textures until the result is a rich tapestry of sound.

The dCS was able to offer a keen view of the entire performance, allowing the listener to pick out individual elements – the fine picking of strings, the metallic ring of the snare, the sonorous presence of the backing vocals, the slightly echoed rhythm guitar. The result was a persuasive sense of accuracy and realism, which added to the believability and the enjoyment of the music.

Interestingly, the DS Bridge II managed to sound even more cohesive and musically engaging, but it couldn’t match the dCS for outright clarity and detail.

The DirectStream’s staging was broad and generous, but lacked the layered dimensionality which allowed the dCS to accurately place individual elements on that soundstage. And it couldn’t replicate the sense of space and ambience achieved by the dCS.

The dCS easily maintained its talent for lucidity and insight when confronted by the scale and majesty of Beethoven’s Symphony No.7, performed here with energy and vigour by the Vienna Philharmonic under Carlos Kleiber.

Arguably one of the seminal performances of the work, the recording captures all the drama, the pathos and the grandeur of the work.

The dCS again displayed its talent for scale and immersion, allowing the listener to delve deep into the essence and passion of the music. The recording places greater emphasis on width than depth on a soundstage that can sound congested on lesser systems, but was allowed ample scope and dimension here.

The attention to detail was exemplary, again without diluting the focus and integrity of the performance, which did much to draw the listener into the performance. The dCS also conveyed the power and urge of the music with authority, and easily tracked the recording’s significant dynamic swings.

The Bridge II was not quite as expansive as the dCS in sound picture terms, nor could it match the British device for finely focussed microdetail and ambient information. But again, there was a pervasive sense of cohesion and balance that made the listening experience compelling and entertaining.

The sound picture may not have been as clearly layered nor quite as three-dimensional, but scale and presence were well represented.

Ultimately, the dCS Bridge provided the bigger, more detailed and more engaging sound – and I have no doubt that when partnered with a dCS DAC, the combined performance potential will be significantly greater still – especially where the dual-AES interface can be employed.

That said, the Network Bridge elevated the performance of the DirectStream to new heights in terms of outright dimensionality, detail retrieval and atmospherics. That the Bridge II sounded as good as it did by comparison should not come as a surprise, either: it benefits from the direct signal paths and specifically engineered-in compatibility that are synonymous with a bespoke, integrated solution.

Using the dCS Network Bridge outside the Roon ecosystem, with the dCS app controlling playback, resulted in a sound that could be considered marginally clearer still, with subtle improvements in transients, dynamics and high-frequency resolution.

Again, this might simply be a system-specific trait, given that in my set-up, Roon uses a headless Mac Mini as the core, while playback via the dCS app would result in a less complex signal path.

A quick word on the dCS app: while it worked perfectly on the iPhone 5S with its below-standard 4-inch screen, the user experience was far more satisfying when running on an iPad.

The extra screen real estate makes using the sometimes tiny virtual buttons a lot easier (especially if you have clumsy fingers like me) and artwork displays more vividly, too.

THE BOTTOM LINE

The dCS Network Bridge exploits the company’s considerable experience with FPGA platforms, careful power supply management and superior engineering to deliver an impressive and hugely competent streaming solution..

For dCS DAC owners, it allows the addition of fuss-free, intuitive streaming functionality with no compromise to sonic quality, while owners of other quality DACs will also benefit from its considerable talents, even where dual-AES or SDIF-2 facilities are not on offer.

VITAL STATS

Platform: FPGA-based
Connectivity: Gigabyte Ethernet
Digital inputs: USB Type A
Digital outputs: 2x AES/EBU, SPDIF RCA, SDIF-2 BNC
Clocking: Auto reclocking (internal), 2x word clock BNC
File format compatibility:
– FLAC, AIFF, WAV up to 384 kHz/24-bit PCM
– ALAC up to 192 kHz/24-bit PCM
– AAC, MP3, WMA, OGG up to 48 kHz/24-bit PCM
– DFF, DSF and DoP up to DSD64 and DSD128
– Apple AirPlay up to 48 kHz
Control: Dedicated dCS Network Bridge app
Dimensions (WxDxH): 360 x 254 x 67 mm
Weight: 4,6 kg
PRICE
R69 000
SUPPLIED BY
Fundipoint.

SOFTWARE
John Scofield – Überjam Deux (Emarcy 44/16 FLAC)
Ry Cooder – The Prodigal Son (Universal 44/16 FLAC)
Beethoven – Symphony No. 7 – Carlos Kleiber/Vienna Philharmonic (DG 44/16 WAV)

ASSOCIATED EQUIPMENT
PS Audio DirectStream/Bridge II DAC
Mark Levinson No.26 pre-amplifier
PS Audio M700 monoblocks
Vivid Audio V1.5 speakers
Synology DS213+ NAS
TelluriumQ Black speaker cables and interlinks
PS Audio P5 power conditioner