Relatability and inclusivity. The top two watchwords of the Darko.Audio YouTube channel that, as of this week, is now attracting as many unique visitors per month as the Darko.Audio website: 250,000 apiece.
In scripting, shooting and cutting a short film about an audio product, our intent is for the bigger picture not to be lost to the details that can otherwise cause the pursuit of better sound to be seen as an elitist geek fest. For some veteran audiophiles, that’s all part of the fun but for newcomers, too much tech talk is a turn-off.
Back on the mothership (this website), we can go for a deeper dive on those details. Here are ten thoughts that didn’t make the final cut of our short film about AudioQuest’s DragonFly Cobalt:
1. The DragonFly’s output doesn’t come straight off its ESS DAC chip from an interceding ESS 9601 headphone driver chip. Ergo, Cobalt, like Red and Black, is a DAC / headphone amplifier.
3. On hi-res audio support, Cobalt is limited to 96kHz PCM. This is a not a limitation of the ESS 9038Q2M DAC chip (which can handle PCM sample rates up to 384kHz) but of Microchip’s USB receiver. The 96kHz ceiling is a side effect of its USB Class 1 status that permits full, driverless compatibility with Android, iOS, Windows, MacOS and Linux.
4. Higher sample rates are possible when streaming MQA to Cobalt. The first unfold is executed in software running on the host device. The MQA stream then enters the DAC at 88.2kHz or 96kHz and within the USB receiver chip’s limits. Once inside the Cobalt, the in-built MQA code executes further unfolds, should they exist, and also MQA rendering.
5. When the DragonFly Cobalt is connected to an iPhone using Apple’s Lightning-USB adapter (sold separately) and called upon to decode Sigur Rós in CD quality content from Tidal, the Cobalt’s light glows green, indicating the presence of a 44.1kHz data stream.
However, stream the same Sigur Rós from Tidal with the AudioQuest DAC connected to the LG V40 smartphone and Cobalt’s light glows blue — a 48kHz stream! This tells us that the Android OS is upsampling the digital audio stream before it is dispatched via the phone’s USB socket. It is not bit-perfect, thus red-carding MQA, which it also resamples to 48kHz. This is not an LG anomaly. The Xiaomi Mi A1 displays similar behaviour.
The workaround is to use a third-party app for music playback: USB Audio Player PRO (UAPP) loads its own USB driver and its bit-perfect mode sidesteps Android’s software volume control and any associated re/up-sampling. Redbook streams glow green. 96kHz streams glow magenta. UAPP supports Tidal, Qobuz and Google Music but offline content is prohibited, not by the streaming services but by rights holders (aka labels).
6. UAPP also supports MQA via an in-app purchase. A purple light on the Cobalt tells us that Tidal’s MQA streams are being handled by UAPP and its USB driver as AudioQuest and MQA (the company) intended.
7. As if OS re-sampling wasn’t enough of an issue, both the LG and the Xiaomi suffer another weakness with an AudioQuest DragonFly DAC lassoed to its USB-C socket: the audible presence of intermittent low-level noise that modulates with the musical signal. UAPP to the rescue: no noise, telling us once again that this noise is a failing of the Android OS and not AudioQuest’s engineering. This noise does not present when a DragonFly is hooked into an iPhone or a MacBook Pro.
8. UAPP sounds better than Tidal or Qobuz’s own apps. It also sounds better than Foobar when streaming music from an Android phone’s internal storage.
9. Another Android plus: the ‘DragonTail’ USB-C to USB-A adapter (supplied with the Cobalt) is more robust than Apple’s own Lightning to USB adapter and, after long-term usage with DragonFlys Red and Black, has proven the more resilient to in-pocket bending.
10. What about the Chord Mojo? It’s quite a bit larger and heavier than the Cobalt and isn’t so easily pocketed when connected to a smartphone. One is portable, the other transportable. Mojo also contains a rechargeable battery, offers coaxial and TOSLINK inputs (as well as USB), and at US$599, is twice the price of the DragonFly Cobalt. I don’t see them as occupying the same product/price category but a good number of YouTube commenters wanted to know so, in a nutshell, the Mojo is more powerful and delivers more detail than the Cobalt but it’s not as graceful with macro dynamics or as relaxed-sounding.
Further information: AudioQuest