Chord Electronics

Mojo 2

£449

Think on this. When Chord's original Mojo DAC/headphone amp landed in 2015, the iPhone 6S was battling it out with the Samsung Galaxy S6 Edge and Sony Xperia Z5. At the time, I was using a Google Nexus 6P. Uptown Funk was everywhere, and Justin Beiber was still a thing. That's how long this hugely successful product has been rocking the portable audio world. Amazingly, only now has its replacement landed, with the team at The Pumphouse down in East Farleigh, Kent, having been working on it since 2018. According to its designer, Rob Watts, this has been “too long”!

UP CLOSE

The new Mojo 2 ups the price slightly, but it's a thorough redesign with some very swanky new tech added. It now has four – not the three of the original – control spheres inset into its beautiful black anodised, bead-blasted aluminium case. Also, gone are the notches designed to hold elastic bands in place when strapping your DAC to your phone – which was de rigueur back in the day.

Another key physical difference is a USB C port, which has been added to its complement of inputs, including optical, coaxial (including dual-data for the M Scaler) and micro USB, alongside a separate micro USB charging port. The unit measures just 83x62x22.9mm (LxWxH) and tips the scales at a modest 185g. Not bad going, as I wish that I'd only added an extra millimetre or two and five grams in the past seven years!

The extra button hands the Mojo 2 an additional menu feature. This multi-functional polycarbonate globe adds mute and button-locking functions, plus access to a four-setting crossfeed adjustment and a range of tone controls (four equalisation bands – lower bass, mid-bass, lower treble and high treble – each with nine positive and nine negative 1dB adjustment steps). This is done using what Rob Watts calls “lossless DSP”, more of which later…

All these shiny new things are well and good, but the real meat in the sandwich for audiophiles like us is the latest generation of Chord Electronics FPGA-based Pulse Array DAC, and Watts Transient Aligned (WTA) filter. This is a bespoke design and not – unlike almost rival DACs – a third party, bought-in silicon chip solution. Think of it as a custom fit in an off-the-rack world – it means that the conversion and filtering algorithms are done completely in-house by Chord.

The new Mojo 2's WTA filter has 40,960 taps – the technical measure of how complex the interpolation filter is – to the 38,912 taps of its predecessor, and the filter core is upgraded to current standards, which Rob Watts says “is a larger change than the taps. There is more to WTA filters than taps!” All the same, as many iterations of Chord DACs have shown us – there is a correlation between the number of taps and the resulting sound. Fans of the company will know that Mojo 2's bigger brother, the Hugo 2 has 49,152, the Hugo TT2 has 98,304, and the flagship Dave weighs in with a mighty 164,000.

This dinky DAC retains its predecessor's analogue output stage, although the coupling capacitor has been removed, which Rob reckons has “tightened the bass and extended definition”. Chord quotes its output as 90mW at 1kHz/300 ohms, and 600mW at 1kHz/ 30 ohms. Impedance is listed at 0.06 ohms, with dynamic range quoted as 125dB, and THD at 2.5V/300 ohms, clocking 0.0003%. Certainly, for a portable DAC, these are exceptional figures.

Arguably, the new Mojo's most interesting new feature is what the manufacturer calls “the world's first fully transparent UHD DSP”. Rob tells us that that the system “perfectly preserves the original music signal, and perfectly performs the EQ filter function.” He adds that, “the key here is being able to define what perfect means for EQ, and then being able to measure the performance – if you can't measure the actual performance, then it's a mere word with no verifiable meaning”.

He has focused on the three things that he thinks are vital to transparent performance – small signal amplitude accuracy, small signal phase accuracy and noise floor modulation. So the Mojo 2's sophisticated new DSP has been designed to address all these technical issues, and more. He continues:

The first I have known about for many years, with many listening tests confirming its importance. The second is when you compare the phase shift from a 0dBFS signal against the same signal but at -301dB. To pass the test, the phase shift needs to be identical at different amplitudes… The original Mojo noise shaper had a phase error at -301dB, and eliminating this gives better depth perception. Noise floor modulation is where the noise level changes with signal level, and is very audible, even well below measurable limits.

IN USE

The Mojo 2 can play files up to 768kHz 32-bit and DSD256, making it very well future-proofed. The sample rate being played back is indicated by the colour of the power button when music is playing, ranging from red for 44.1kHz to pale violet for 768kHz and clear for DSD. Much to my relief, the Mojo 2 plays nicely with the original Poly streaming and SD card player widget. The one caveat is that this streaming accessory needs to be running v3.0 of its firmware, which can be done via Chord's GoFigure application. The latter also seems to have settled down some since its early days. Adding a Poly to the Mojo 2 means that Roon becomes an option, as does playback from an SD card or Bluetooth. Lovely!

Battery life is said to be a reasonable eight hours which seems about right, depending on the headphones and volume levels, of course. This is down to a new higher capacity rechargeable battery; “things have moved on since 2015”, quips Rob. He says that on the original Mojo, the battery fed its amplifier section directly, but now it is fed by regulators, ensuring low PSU noise when using it plugged into the mains. “We can see the benefit of this in that crosstalk (i.e. PSU noise) is considerably better with Mojo 2 at 118dB.”

Certainly, the new Mojo 2 remains cooler when charging than its predecessor but still gets rather warm. This isn't a big deal, not least because that gorgeous aluminium case acts as one giant heatsink. During regular, portable operation, the unit does warm up, but not startlingly so – even when you're sharing your wise musical selections with a friend, thanks to Mojo's two 3.5mm headphone ports that can be used at the same time. There's still no way of independently controlling the volume through each output, though.

THE LISTENING

Chord's Mojo was always a great performer at the price, which explains its stellar success. The song remains the same for Mojo 2. It has staggering detail resolution for a portable – even better than before – but the icing on the cake is how the new 2 can organise everything into a cohesive and musical whole. It makes for truly addictive listening sessions, no matter whether on the go or at the desk. Those who listen at work can expect a major productivity drop!

Plugging in my high-end Ultrasone Edition 15 Veritas cans, the Mojo 2 sounded fantastically crisp and lithe, picking its way through a 44.1kHz copy of Heaven 17's Penthouse and Pavement – which is a great recording for its age. Compared with my usual desk set-up of a Chord Qutest DAC crunching the digits provided from my PC, and then through the valve-powered Auris Euterpe headphone amp, this new DAC/headphone amp had an ever more insightful presentation. Without the warmth of the Euterpe's valve analogue output stage, the Linn LM-1 programmed rhythms were whip-crack snappy, and Josie James's backing vocals were wonderfully clear in the mix. It was certainly helpful to be able to dial down the highs a little on the Mojo 2 at this point, showing how handy that fancy DSP system is.

By stark contrast, a 24/96 FLAC of Stevie Wonder's Innervisions illustrated how the new baby Chord can present a recording without stamping its digital boots all over. Here was a distinctly nineteen seventies recording, with all its organic analogue warmth clear to hear. Yet still, the Mojo 2 was able to excavate copious amounts of detail. I could clearly pick out the timbre of the Fender Rhodes piano, and the glorious blurting sound of the Moog synth bass, without the Mojo 2 overcooking the bass or over-egging the mids to give a false impression of elevated detail retrieval.

One of the big draws of the original Mojo was how the battery-powered DAC/amp was gutsy enough to power planar magnetic headphones. Dusting off my venerable Oppo PM1s, and the new one certainly had no issue with making them sing. In fact, it was the Astell&Kern Kann Alpha, at more than twice the price, that I last heard a pocketable player get so much from these long-term favourites of mine.

It was the same story with more up-to-date open-backed planars in the shape of Sendy Audio's Peacock phones. Attached to Poly and using Roon to stream What Are You Going to do When You're Not Saving the World? from Hans Zimmer's Live in Prague, displayed a convincingly realistic tonal balance and an impressive sense of scale. Playing around with the crossfeed options did seem to increase the soundstage, with moderate (blue) being my Goldilocks zone if I had to choose one.

The great thing about this little box of tricks is that this performance is not just about being indoors – slip the Mojo 2 into your jacket, head out, and that vast acoustic vista comes with you. This is where the “lockdown mode” comes into its own, and it's not before time that this feature has appeared. For me, pairing the Mojo 2 with a pair of Meze Audio's Liric closed-back planar headphones was the icing on an already show-stopping cake. Recently I have been shoving a Chord Hugo 2 into my coat when going out for a walk, and I was honestly not expecting the Mojo 2 to come anywhere close to what the Hugo can do, but it does. Of course, the bigger and more expensive portable Chord DAC is still better, but the gap has narrowed – proving that the new Mojo is a proper step up sonically from its already class-leading predecessor.

The power and dynamics of Tool's Fear Inoculum demonstrated the new Mojo's surefooted ability to deal in the grandiose with huge swathes of impact and then – at the drop of a hat – become refined and delicate. Additionally, this well-penned slab of prog metal also underlined this dinky DAC's sense of organisation. Because of this, long listening sessions proved unfatiguing, as every note is given the attention it deserves without requiring undue exertion from the listener.

Be forewarned, though, as the new Mojo 2 is so transparent that it doesn't suffer poor recordings or masters gladly. It's not a euphonic device that's designed to make everything sound universally good – nor was it ever designed to be. It doesn't try to shame them, but nor will it flatter. This tells us it's aimed at the more discerning end of the head-fi market rather than casual consumer electronic users.

THE VERDICT

Like the smartphones we all carry around, some things change, but some things stay the same. The new Mojo is the new king of portable headphone amplifiers, just like its predecessor was back in 2015. Despite so many things being much more expensive now, the price premium of this new model is very modest, and you get a commensurately better product.

Its sound is audibly superior – tighter, cleaner and more detailed, and musically, it's delightful. There are moments when you have to remind yourself that this is a portable device and not a large desktop unit, such is its performance and sense of scale. Also, it's now a more sophisticated thing to use - the new features are very welcome and certainly not gimmicks – quite the opposite. Whether plugged into a computer, phone or streaming via Poly and Roon, the Mojo 2 is not only a highly capable DAC/headphone amplifier but a lovely bit of kit that should still be giving great service in five years – and beyond.

For more information visit Chord Electronics