Two and a half years after releasing Poly for its award-winning Mojo, Chord Electronics has treated its flagship portable DAC/headphone amp, Hugo 2, to an add-on streamer/server of its own. Having reviewed Hugo 2’s larger table-top sibling, Hugo TT 2, last autumn, now seemed like the perfect time to see how the portable model measures up with its newly expanded functionality courtesy of the aptly-named 2go.
Debuted in 2017, the £1,800 Hugo 2 is the pinnacle of Chord’s portable line. Like its predecessor, it functions as a standalone DAC with line level output for an external amp or it can be used as a combined DAC/preamp to drive headphones, powered speakers or an external power amp. Available in silver or black, the aircraft-grade CNC’d aluminium casework has a low-profile design measuring just 23mm high and weighing 390g, with four top-mounted spherical control buttons at one end.
These push buttons use polychrome illumination to indicate power, crossfeed, input and filter settings. The volume roller gradually changes colour as the volume level is increased or decreased in 1dB increments and a circular ‘viewing window’ to the internal circuits illuminates one of eleven colours to indicate source sampling rate. Hugo 2 benefits from a remote that controls all of the unit’s functions from a distance, making it practical for use in typical domestic systems.
Four digital inputs are provided – USB (micro), coax (3.5mm) and optical (toslink) plus extended-range aptX Bluetooth – with maximum supported sampling rates twice and four times that of its predecessor for PCM and DSD, respectively. The USB input now supports 32-bit/768kHz and DSD512, coax 32-bit/384kHz, optical 24-bit/192kHz and Bluetooth 16-bit/48kHz (AAC is not supported so Apple users are bumped down to the basic SBC Bluetooth codec). Additionally, the seemingly single 3.5mm coax input is actually a dual-input and can be used to input 768kHz from sources that support dual-data mode, such as Chord’s M Scaler upscaling device,.
The second micro-USB port is for charging the two internal 3.7v 2600mAh lithium ion batteries which provide over 7 hours of playback and take around 4 hours to recharge using the supplied 2.1A charger. This can be used to power the unit without depleting the batteries. Outputs include analogue stereo RCA and two single-ended stereo headphone sockets (6.3mm and 3.5mm).
Improving upon the performance of the original Hugo, on the amplifier side digital DC servos replace the inline capacitors in the output stage, delivering more power with lower distortion and even lower noise floor modulation. Hugo 2’s Class A output stage is apparently capable of supplying 5Vrms with peak output currents of 500mA. This translates to 94mW into 300Ω, 740mW into 33Ω and 1050mW into 8Ω, catering for most headphones with the exception of stubbornly inefficient planar magnetics. A super-low output impedance of just 0.025Ω means power transfer is linear, even into loads with bumpy impedance curves.
Rated for use with headphones from 8Ω to 800Ω, a signal-to-noise ratio of 126dB with noise floor modulation that is claimed to be so low it can’t be measured delivers the deepest of black backgrounds. This may not be so easily noticed over loudspeakers, but headphone users – especially IEM wearers – should hear substantial improvements in low-level detail retrieval.
On the digital side, Hugo 2 sports a Xilinx Artix 7 FGPA chip with a ten element digital filter that has almost doubled the 26,000+ taps provided by the previous four element filter to more than 49,000 taps, while a revised oversampling WTA algorithm harnesses this additional processing power to best effect. For those unfamiliar with their unique approach to D/A conversion, instead of using “off-the-shelf”, pre-programmed DAC chips Chord use custom-coded FGPAs and patented Watts Transient Alignment (WTA) algorithms.
Equivalent to the size of a small paperback novel, Hugo 2’s form factor is perhaps still a little too large to be considered a truly portable device. I suspect only the most ardent audiophile would insist on squeezing it into their jacket pocket and tethering it to their smartphone for on-the-go listening. Its versatility, battery life and size does however make it perfect for transporting from A-to-B, whether that’s between rooms at home, into the garden, workplace or any other space, so long as you have a music source to connect it to.
Sound quality
I used Hugo 2 mainly as a DAC/headphone amp in various rooms around the house connected to a MacBook via USB with the following headphones: Audio-Technica ATH-MSR7 and ATH-ADX5000, Focal Utopia, Sennheiser HD600, HD650 and HD800S. Tied to Apple’s ecosystem I was sadly unable to take advantage of Hugo 2’s aptX Bluetooth facility. (The basic SBC codec provides acceptable performance with an iPhone or iPad as the source but obviously isn’t a patch on Hugo 2’s wired connections and should really be viewed as a convenience). I also couldn’t resist putting Hugo 2 to the test as a DAC/preamp in my main system, plumbed into a Mac Mini by USB and driving a Yamaha A-S3000 stereo amplifier and Celestion Ditton 66 loudspeakers. In both contexts there is a clear family resemblance to the £3,995 TT 2; the portable model displays many of its bigger brother’s admirable qualities.
Hugo 2 is a very clean and nimble sounding DAC/preamp and reveals an abundance of inner detail and space in recordings. Catching up on office work with the Chord playing in the background, I was frequently distracted from the tasks at hand and it wasn’t long before I downed tools and snapped into critical listening mode; this DAC’s pacey and wide-open presentation deserves your undivided attention. It particularly excels in teasing out the instruments in a mix and placing them generously across the width of stage. Depth of field is also excellent, though the front wall doesn’t quite ‘disappear’ to the extent that it does with TT 2.
While the original Hugo was positively received, some did perceive a hint of brittleness in its timbre. It seems Chord took this feedback onboard as to my ears Hugo 2 is very transparent and doesn’t impart much of a signature at all. It’s slightly on the lighter (but not brighter) side of neutral; tonal colours aren’t quite as strongly inked as with my reference Schiit Yggdrasil 2 DAC, Hugo 2’s brushstrokes are more delicate by comparison. Also, Hugo 2’s contouring of shapes isn’t quite as precise as Yggdrasil’s or TT 2’s, but its exceptional fluidity makes it easy for the listener to ride along with the rhythms and follow their every twist and turn.
If desired, Hugo 2’s speedy transient response can be dampened to a degree by engaging a stronger noise-shaping filter. Filter 1, referred to as ‘Incisive Neutral’, is the default 256x oversampling filter and the most transparent of the four settings provided. Filter 2, AKA ‘Warm’, uses 16x oversampling for a slightly warmer tone. Filters 2 and 4 are designed to be used when playing DSD and apply additional roll-off to the aforementioned Incisive and Warm filters to remove unwanted supersonic noise and prevent intermodulation distortion. As with the TT 2, I found the differences to be marginal but generally preferred the pristine crispness of the Incisive Neutral filter on well-mastered music and engaged the Warm filter to help take a slight edge off rougher recordings and those lacking tonal mass.
Like TT 2, Hugo 2 provides four crossfeed settings, ranging from none at all to a broad crossfeed. This delays and mixes a small part of the right channel signal into the left channel and vice versa to make headphones image more like loudspeakers and reduce listening fatigue. I find Chord’s digital crossfeed implementation simple to use and very effective and I’m glad it has become a staple feature; it’s subtle enough not to interfere with the structure of the music yet significant in its alleviation of fatigue even on the lowest setting. This is evident as soon as the facility is bypassed and the somewhat unnatural sensation of instruments isolated in the left and right channels reappears.
I also had the opportunity to try this DAC with Chord’s latest streamer/server, 2go, a portable module that bolts onto Hugo 2 and transforms it into an app-controlled, WiFi- and Ethernet-enabled DAP. Eliminating the USB cable between Hugo 2 and my MacBook or iPhone as I moved between rooms was very liberating and I experienced no objectionable downgrade in sound quality by Airplaying 16-bit/44.1kHz lossless audio to 2go via WiFi. Streaming high-res LPCM and DSD from both my NAS and a 400GB microSD card showed 2go to be a fully transparent intermediary, the latter granting me access to a very convenient cache of reference quality music even when I wasn’t connected to my home WiFi (2go can create its own WiFi network).
Verdict
After being suitably impressed by Hugo TT 2 last year, I had pretty high expectations of Hugo 2 and am pleased to find it does not disappoint. It doesn’t put as much ‘meat on the bones’, nor is it as effortless in its handling of dynamics, as its larger and more expensive table-top sibling. It does however get surprisingly close, quite an achievement for a device that’s less than half the price and 1/8th the size. At £1,800 Hugo 2 it is still a fairly big investment, but it almost certainly sets the benchmark for technical performance from a portable and versatile DAC/headphone amp. For those craving the highest levels of detail retrieval and speed, Hugo 2 delivers in spades.