Chord Mojo 2 Portable DAC/Headphone Amplifier Review
If you are a member of the Head-Fi community, Chord has been part of your life for the past decade with its award-winning, and often groundbreaking products. While many of the British manufacturers' products are very expensive, there are a growing number below $1,000 that merit serious attention from both headphone enthusiasts and music listeners looking to assemble a first-class system for either the home or desktop. Products like the Chord Mojo 2 offer a level of technical sophistication you don't see in very many products in the price range or even above it.
Rob Watts has been the primary designer and engineer at the company and the driving force behind some industry-changing products in the desktop and portable audio categories.
EIC Ian White, sat down with him at the recent CanJam NYC 2022 and came away incredibly impressed with both his design philosophy and the myriad of products on display at the show.
We've spent some time with products like the Chord Huei and discovered that Chord can deliver almost anything at this point and keep the same form factor and quality — and still make it attainable.
Watts has been very vocal about his designs and how they set Chord apart from a lot of companies and his thoughts about MQA. (Don't expect Chord to support MQA anytime soon). Chord is distinct in that they design their DACs using a field-programmable gate array (FPGA) instead of a dedicated DAC chip.
For a small British company with a handful of employees, this is a massive undertaking. Most companies rely on ESS, AKM, or Cirrus Logic to provide the DAC chip and knowledge of the internal workings of the DAC.
Chord literally designs their DACs from the ground up; a lot of the work is focused on the software which allows firmware changes on Chord devices that would require hardware changes in most other companies' products.
Proponents will refer to Chord as a true manufacturer while other companies using chip DACs are simply assemblers. Detractors will point to the costs of the Chord lineup and suggest that in-house R&D causes prices to be much higher than similar products by other competitors.
While that may be true — the reality is that Chord offers some of the best sounding audio components in the world and most of them can compete with products that are substantially more expensive.
The Chord Qutest is possibly one of the best sounding DACs below $3,000 and it doesn't cost anywhere near that.
When the first generation Mojo (mobile Joy) arrived on the market, the dongle really didn't exist yet and most people were either using a DAC/Amplifier or a DAP. It was not uncommon to see stacks of devices where one provided the source and another the DAC/Amplifier functionality.
The Chord Mojo provided wireless phone users an option that was as good or better than most DAPs on the market. Fast forward a few years, and the Mojo is still usable but the market has shifted considerably.
For starters, the Micro-USB ports on the Mojo now date it because most devices now use USB Type-C ports. The Dongle DAC market has shifted expectations of what a portable device should be as well; most consumers now expect a smaller and lighter device.
The Mojo 2 is very similar to the first generation Mojo, with the exception of a four-button control system (three on the original) and a USB Type-C input. It is the same size and shape and I wouldn't say that the weight has changed all that much. Except for the aforementioned USB Type-C input, the connections are the same.
The fourth button adds a new tone control to the existing power/input switch, and the volume adjustment buttons. The outputs are still dual 3.5mm ports on the end opposite the inputs; Chord is not a proponent of balanced audio, so I didn't expect to see them bow to industry pressure and include a 4.4mm port.
Those who have invested in the Chord Poly that extends the functionality of the Mojo into a streamer will appreciate the fact that port placements are the same as the earlier model; which means that Poly users are not left out in the rain twiddling their thumbs.
Internally, a new generation of FPGA offers more substantial changes. Chord calls it the UHD DSP or Ultra-high Definition Digital Signal processor, and while most of the market debates 16-bit/24-bit DACs, the Mojo 2 uses a 104-bit/768kHz FPGA central core.
Yes. We know that there isn't music yet at that bit rate but that's not the point of the design.
The DAC uses Delta-Sigma logic but with noise shapers that use a much higher frequency than most Delta-Sigma DACs which allows for the preservation of the smallest detail of the original signal.
Chord has a podcast with Rob explaining the changes made to the noise shapers and how it impacts the overall sound quality. In a nutshell, the average Delta-Sigma DAC converts the 5 or 6 most significant bits and then uses a feedback mechanism (noise shaper) to reconstruct the remaining bits rather than actually converting the entire 16 or 24-bit signal.
This allows for a speed improvement over full depth conversion but means that often the micro-details are at best, an estimate of what was in the original track.
This is why proponents of R2R prefer it over Delta-Sigma DACs because R2R converts the entire signal rather than using feedback. R2R brings a host of other problems though, so Chord finds the best solution to be a Delta-Sigma model with noise shapers operating at much higher than average frequency.
With comparisons made five times more often than the standard chip-based DACs, more detail is preserved and more dynamic range as well.
The other big advantage of the FPGA DSP model is that tone controls can be implemented on any desired portion of the frequency range without degradation of sound quality. The fourth button introduces a menu system that offers access to crossfeed adjustments and the lossless tone controls so users can tune the Mojo2 to their specific headphone or IEM.
The tone controls offer 4 bands, lower bass, mid-bass, lower treble, and upper treble with 18 steps of adjustment in each band. The volume control range is from +18 dB to -108 dB, with two discrete gain levels offering even more flexibility.
Along with the changes to the FPGA, the Mojo 2 now uses a digital DC servo with a new interpolation filter design across the 40 DSP cores. This helps further reduce noise and improve SNR as the new design eliminates the coupling capacitors used in the previous model.
The FPGA is also employed for battery management in the Mojo 2 giving it much-improved charging rates as well as longer and cooler operation. I had no trouble getting a full 8 hours of listening time at normal listening levels (78 dB).
The other cool thing is that the Mojo 2 bypasses the internal battery altogether when in desktop mode which helps preserve the battery life.
The changes to the sound are incremental and the Chord house sound is very much still in play. The dynamics and detail are both improved with more micro-detail compared to the original although again, it may take direct A/B testing to really notice some of the smaller nuances.
The area where I think the difference in the original and the Mojo 2 is most noticeable is in the soundstage where the Mojo2 has a great live performance feel to the sound with instrument spacing and imaging easily besting the previous version.
For those that are not in love with the near-neutral tonal signature, the tone controls now give the user to the option to make the Mojo 2 as bass-heavy as anyone could realistically expect and it does so without notably muddying the sound.
I've often praised bass boost circuits that offer small gains while retaining the transparency (iFi Audio X-bass), as usually the bigger the boost — the more it veils the sound.
Chord does seem to have solved this as I was able to add +5 steps to both the low bass and mid-bass and not lose clarity in the process. At the extreme end, I do think it overwhelms, so even if cleaner than average, I see the real benefit of the tone controls being the first 3 or 4 steps where calculated adjustments can be made rather than an all-out assault on the original signature.
The build is very solid and the UI while having a bit of a learning curve, is still miles ahead of most dongles that offer little or no control surface at all. The issue for many will be price. At $845 retail in the USA, it is a big pill to swallow when most dongle DACs are retailing at $299 or less and even the M8V2 is $100 less.
The things that make the Mojo 2 worth the money are that it is the highest resolution DAC ever offered in a portable device and revelatory sound quality that is hard to ignore.
Its tone controls are easily better than pretty much any other device I've tested without going to a fully parametric EQ, and for those already invested in the Chord ecosystem, the Mojo 2 maintains compatibility with the other Chord modules (Poly).
Chord has always had a cult-like following and I suspect the Mojo 2 will continue that trend with proponents pointing to all the technological advances while detractors point to the price.
The Chord Mojo 2 is near the top of the pyramid with things like the Centrance M8v2, but it also sits near the top in price which will keep it from selling as widely as it might otherwise.