Introduction
With my iPhone 7 no longer having a headphone jack, and with the portable headphone amplifier and DAC market getting more competitive than ever, I thought it was time to consider making the switch from my larger Schiit Audio Lyr 2 class A hybrid desktop amp, and an external DAC, to an all-in-one portable unit. The two of such devices I tried, in order to see which one would win me over, were the OPPO Digital HA2-SE, and the Chord Electronics Mojo. While these two devices are in my opinion geared toward a different type of user (and price should be an indicator, with the OPPO being USD 300 and the Chord being USD 600), I nonetheless thought it would be worthwhile to compare the two to see if the Mojo really is worth double the price, or for the average person the HA-2SE is the better value proposition.
Packaging
Both devices ship with nice packaging, with the OPPO being a large box than the Mojo.
What comes in the box, on the other hand, is different...
In the HA2-SE's packaging, you get a USB Micro-to-Micro OTG cable for use with your Android phone, you get a 3.5-to-3.5 interconnect cable for using line out to an amplifier or from another device with a 3.5mm jack, a short USB-A to Lightning cable for use with your iOS handset, two silicone bands for strapping your DAP to the HA2-SE, a Micro USB charge and sync cable, and 5v/5 amp quick charging power adaptor. Everything you need to connect HA-2SE to your computer/DAP and get it up and running is all there.
The Chord comes with a 2 inch Micro USB cable....and that's all you get for your king's ransom of 600 dollars. But more on the skimpy accessories later.
Form Factor
Both the HA-2SE and Mojo are devices one can be proud to own. Both the HA-2SE and the Mojo are made from Anodized aluminum and both exude quality. The OPPO is the same length of an iPhone 6/6s/7 4.7 inch model, and is a couple ounces heavier, with a solid but not overly heavy feel. It feels well balanced in the hand, and is about a third of an inch thick. The HA-2SE also comes wrapped in a genuine pebble-grain leather cover with white stitching, so it has extra tactility to keep in your grasp, and does not need a case. The Mojo takes up about the same footprint as a deck of 52 cards, or a pack of cigarettes. It only comes in an anodized black finish, and has three acrylic marbles that light up different colors and function as volume controls and a power button. They rattle slightly if you shake the Mojo, but other than that it is an incredibly solid little device that feels considerably heavier than its footprint would suggest (0.4 pounds or 0.18 Kg). It also is rather slippery compared to the leather-wrapped HA2-SE.
The controls are different. The Mojo has 2 buttons to control the digital volume adjustment, no gain or boost settings, and no manual input selector (inputs are handled automatically with USB prioritized). The HA2-SE has more hardware features available, and more little trinkets and buttons. The volume/power knob is analog, and has a satisfyingly oily feel while it is being turned, in addition to a knurled finish to grip onto. The battery status indicator button illuminates a total of 4 lights when you press it, much like a MacBook. The input elector is aluminum finished, and the bass boost and gain switches are metal switches like the mute switch on iPhones. The HA-2SE has more nice little finishes than the Mojo, which has a very simplified but elegant control layout.
The HA-2SE is made in the People's Republic of China, while the Mojo is made in England, UK.
Input Options
The HA-2SE and Mojo have a few different inputs, and this reflects the target audience, what each company expects the respective users of the devices to prioritize, and which sort of gear they expect their devices to be plugged into.
The HA2-SE has three input options: a 3.5mm line-in jack, a Micro USB for use with a computer or an Android phone or DAP, and a USB A port for connecting to an iPhone/iPod Touch/iPad. OPPO clearly intended for the HA2-SE to be used by the average consumer who would likely plug their MP3 player, cell phone or laptop into the HA-2SE, and the amplifier comes appropriately accessorized.
The Mojo on the other hand comes with three different connectors: a Micro USB, much like the HA-2SE; a 3.5mm coaxial input; and an optical SPDIF/TOSLINK input. These input options suggest that Chord intends for the Mojo to be run primarily off of higher end equipment and DAPs, which means that the Mojo was intended to be purchased by more seasoned audiophiles, or users with more disposable income to buy more niche dedicated DAPs like Astell and Kern AK100s, AK120s, AK240s that have more exotic digital output peripheries. There is no line-in analog input, only 3 digital inputs. Different devices for different market demographics, it would seem.
Connecting to an iPhone with the Mojo and the HA-2SE is also a different story. The HA-2SE uses a USB A port, which allows you to connect any sort of MFI-certified USB-to-Lightning cable you want into the HA-2SE. The lightning cable that comes with the HA-2SE picks up fizzing and radio antenna interference from the iPhone when the phone is receiving a radio signal, but other lightning cables I plugged into the device did not have this interference problem. The HA-2SE also fits nicely to the iPhone to create a fairly streamlined package.
The Mojo, on the other hand, does not have a USB A port, which means that in order to connect it to your iPhone, you must use a male-to-female USB to Lightning adaptor. Apple sells the USB Camera Adaptor for 30 dollars, so if you want to use the Mojo with an iPhone, then you need to add another 30 dollars on top of the purchase price. And when you connect the Mojo to your iPhone, you get this:
The Chord Mojo CAN be accessorized with a USB module, which you can plug the
iPhone Camera adaptor into, but the Mojo accessories pack is an extra 100 dollars on top of the 30 for the adaptor. The Mojo when connected to the iPhone also picks up radio antenna interference when it is close proximity to the phone, so you need to either have airplane mode on, or simply use a longer Micro USB cable.
FiiO does sell their own micro USB to Lightning cable for 30 dollars, and I have heard that it works on the Mojo, but I cannot confirm this myself. Either way, there are a few connectivity options for hooking your Mojo up to an iPhone, so be creative.
For iPhone users, the Chord Mojo is less
intuitive to connect to an iOS device in comparison to the HA-2SE. And in addition, since the HA-2SE uses a USB A port, you can use approximately 2000 mAh of its 3000 mAh battery to charge an iPhone. It is not a life-changing feature, as the HA-2SE charges the iPhone slowly and will stop charging the iPhone after the battery of the HA-2SE drops to 25 percent, but it still is a nice little additional feature to have in case your iPhone is going dead.
Batteries
The HA-2SE has a 3,000 mAh battery, and with the Quickcharge cable and power brick included, will charge from empty to full in 1.5 hours. The battery is rated at 7 hours when using the amp and DAC and plugged into a moderate load headphone, and about 13 hours when just using the line-in and bypassing the DAC stage. I found this rating to be accurate, with the HA-2SE delivering close to the advertised figures. The fast charging ability is another big plus with the HA-2SE.
The Mojo, on the other hand, takes approximately 4 hours to charge when plugged into a 1 amp power connection. Chord does not specify the size of the battery, but if the Mojo limits the power input to 1 amp maximum and does not slow the charging speed when the Mojo reaches a higher charging level, I may be able to say that the battery is probably around 4,000 mAh. Using the DAC stage is mandatory, so with a modest IEM or headphone load the Mojo is rated at 10 hours of battery life, more than the HA-2SE. I have also found the battery life to be consistent with what Chord states. Note that the Mojo has a separate Micro USB input for charging from syncing, in order to cut down on USB bus power noise.
Power Outputs
The Mojo has more power than the HA-2SE, with the HA-2SE having a maximum output of 300 mW at 16 ohms and 30 mW at 300 ohms, and the Mojo at 720 mW at 8 ohms and 35 mW at 600 ohms. I found that the Mojo was able to push my headphones cleaner and louder, but for users with somewhat efficient headphones like the Sony MDR-Z7 and Oppo PM3 should have plenty of power for your needs.
DAC Performance
Both the Mojo and HA-2SE can handle a maximum of 32 bits and support DSD files, with the Mojo having a maximum upsampling rate of 768 kHz, while the HA-2SE with a maximum of 384 kHz.
UPDATE: Due to a discrepancy pointed out by another user, the the Mojo does
NOT have a true line-out setting. That setting is just a 3v fixed volume out. The HA-2SE is the
ONLY device of these two that can function as a line-out DAC.
And finally, the Sound Quality
For this test, I used my Audioquest Nighthawk and AKG K712 Pro.
Both devices perform exceptionally well, with each one a dynamic and engaging sound signature. I would say that the Mojo has a highly refined, neutral-to-slightly-dark, powerful sound with a very agreeable frequency range from top to bottom with tons of detail. The HA-2SE on the other hand has a more forward, more treble-sparkly sound signature. The HA-2SE, in comparison to the Mojo, has a noticeably brighter sound that makes it sound larger in the soundstage compared side by side, whereas the Mojo is comparatively darker. This treble energy on the HA-2SE is likely due to the slightly mid-to-treble-forward sound signature of its Sabre ESS DAC chip. There is some "Sabre Glare" present, but it only presents itself when paired to more forward headphones. Here is my comparison with both devices paired with different headphones.
Audioquest Nighthawk:
Both the Mojo and the HA-2SE paired equally well with the Nighthawk, bringing in the midrange and tightening up the bass, which tends to dominate the Nighthawk, and often has that "ambient" or "always on" sound signature that adds to the liquid feel of the headphone, but can make the vocals feel somewhat distant or overwhelming when the Nighthawk is not given enough power. I would have to give the slight nudge here to the HA-2SE, as it gives the Nighthawk midrange more presence, and it adds to a more engaging experience. The Mojo is no slouch though, and I would gladly take it paired with the Nighthawk.
AKG K712 Pro:
Now here is where the "Sabre Glare" problem with the HA-2SE begins to show its ugly side, especially when hooked up to a mid-forward headphone. Allow me to explain. AKGs are known for having a 1-2 kHz energy peak in what is called the presence region. This is where contralto singers (e.g. Adele, Rebecca Ferguson, and Alicia Keys) dominate in the frequency spectrum. This for some people provides a more raw and authentic and engaging sound experience, but for many other people this shoutiness is what gives AKGs an unfavorable reputation as being grating headphones to listen to horns, saxophones and women singers. And while the K712 has less of this peak than its Q701 and K701 siblings, it still exhibits this trait to a certain extent. And the HA-2SE's glare, in combination with the K712's glare at this same frequency, ends up being a harsh and stressed sound that got on my nerves after a while. The Mojo with its somewhat darker sound, thicker bass sound and additional power to drive the K712, was a far better pairing with the K712, and did not exhibit those harsh treble spikes like the HA-2SE did.
Overall, I found the Mojo's somewhat darker and smoother sound signature to work better with a wider variety of headphones, from dark and bass-heavy to lean and bright. The HA-2SE is most in its element when driving fairly efficient, dark headphones that could use some extra treble energy to bring forward more dynamics. I prefer a darker sound signature with my equipment since I find it behaves better with more headphones, but if you prefer a brighter and more forward sound signature, then the HA-2SE is the one for you. The bass boost was a nice feature to have on the HA-2SE that I wish the Mojo had, and it was a great way to add some more bass to headphones that may not have enough bass thump, such as the Beyerdynamic DT880 or the AKG K612 or K712.
Conclusion: Which One Should You Get?
Choosing between the HA2-SE and the Mojo is rather simple. If you want the best value device for your money, and you are primarily an average consumer who uses their Android or iOS smartphone for a source device, then the HA-2SE is hands down the one for you. It comes with all the accessory attachments you could want, and the ability to charge the iPhone is a huge plus. In addition, the quick charging capability is a big bonus, especially if you use Samsung or OPPO phones that support this feature and you want to get your portable amp/DAC up and running for use on the go. The line-in jack is also a big plus if you want to stretch out the battery life on the HA-2SE.
If you have a large fleet of headphones and sensitive IEMs that vary widely in sound signatures from dark to bright, you have a need for a more powerful device, and you use more boutique DAPs such as Astell and Kern devices that use coaxial or SPDIF outputs, or you use higher end receivers and CD players, then the Mojo is the device you should consider. You are paying twice the price to get probably the most high-end DAC in a pocketable DAC/amp unit.
For 90 percent of you out there on Head-Fi, go with the HA-2SE. You will not be disappointed. And for those of you to whom those more niche factors are relevant, give the Mojo a try at your local Hifi store or headphone meet up. Chances are you will be pleasantly surprised by how much performance you can get in such a little device, and how well it goes with picky headphones. Stay tuned for my Chord Mojo Review, and thanks for your time.
