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Incremental Improvements...or the start of a new line?

A Review On: iFi Audio micro iDSD

iFi Audio micro iDSD

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Pros: Lots of inputs and outputs, great features, delightful sound quality

Cons: Ridiculous USB type-A input, excessive size/weight for portable use, too many switches in too many places, loud POP! on power-up/power-off

First, I'd like to thank Lawrence and the folks at iFi Audio for lending me a micro iDSD Black Label DAC for a week so that I could experience it firsthand. If you're reading this review, I'm assuming you fall into one of three categories:


  • you have an iFi DAC and you're wondering if the micro iDSD Black Label is a worthwhile upgrade
  • you're in the market for a transportable DAC and are curious about iFi's new flagship product
  • you've followed a link to this page but otherwise, have no idea what this thing is about


iFi Audio is a brand that requires little introduction here on Head-Fi, but in case you missed the massive crowd design topics in this forum that are associated with the micro iDSD, I'll provide a brief introduction. iFi Audio is a subsidiary of AMR (Abbingdon Music Research), which is one of the UK's largest manufacturers of high-end audio systems. AMR is famous for their Series 77 and Series 777 products, including the highly regarded DP-777 reference class DAC with NOS tubes. For the performance it provides, this 25.4 lb monster is a great value even at its lofty $5K USD price. The problem? Well, apart from cost, it's not very portable!


In the US, the assembly of gear that renders sound into a room is commonly referred to as a "stereo", even if many more than two channels are enabled. The term, "high-fidelity" is an adjective that describes the quality of a stereo. In the UK, the reverse is true; the term "hi-fi" is a noun, not an adjective, and "stereo" indicates the number of channels supported by the hi-fi. You go to your UK friend's house to listen to their "hi-fi", not their "stereo."


The name "iFi", then, is a personalized version of "hi-fi". Like that certain American company that is keen to put the letter "i" in front of lots of nicely packaged products, "iDAC", "iDSD" and similar names indicate that these are personal entertainment products with trickle-down technology from AMR. Think of iFi Audio as the "personal hi-fi" (or "i-fi") arm of AMR.


Ignoring their Pro and Retro lines for a moment, iFi Audio's components come in two sizes: "nano" and "micro". These sizes share the same six-sided cross-sectional dimensions of roughly 2 1/2" wide by 1" tall, differing only in length--3 3/8" for the nanos vs. 6 1/8" for the micros. While too thick to fit unobtrusively into a pocket, these are seriously small components compared to what you'll typically find in a desktop or rack audio system.




I think of iFi Audio as a one-stop shop for computer audio. In addition to five native DSD-capable USB DACs plus a USB to S/PDIF interface, their product line has the greatest depth and breadth in USB power and signal clean-up devices on the planet...by a huge margin. Their emphasis on purifying the power that is fed to the DAC is particularly telling--it indicates that iFi Audio has a deep understanding of how and why clean power is important to computer audio, and that understanding drives their product design and product enhancements. The most recent product to benefit from this understanding is the new micro iDSD BL.



Those familiar with the original micro iDSD DAC/amp will find nothing new in terms of function and features with the Black Label model. All of the switches, toggles, inputs and outputs have been duplicated in the new product. The micro iDSD DACs come nicely packaged with a black velvet pull string bag, USB type B to A adapters, USB extension cables, RCA cables, a short 1/8" TRS patch cable, a TOSLINK S/PDIF optical coupler, a gold 1/4" to 1/8" TRS adapter, and elastic bands to strap the DAC to a smartphone or portable player. My original micro iDSD kit also included a set of stick-on rubber feet and a pair of thick plastic spacers to keep the DAC and whatever it is strapped to from scratching each other. I have found the rubber feet to be handy on my micro iDSD to keep it from marring the table or sliding around, but the rubber feet and the black velvet bag are somewhat mutually exclusive, so I can see why iFi dropped them from the BL's packaging. They are easy enough to find at your local hardware store if you want them.


You might never know it by just glancing at the iDSD BL, but it sports three digital inputs (USB, TOSLINK and COAX S/PDIF), one analog input (1/8" TRS), one digital output (COAX S/PDIF), and two analog outputs (1/4" TRS and RCA, fixed or variable), plus a USB charging port. That's a crazy amount of I/O for such a small device! Think of the iDSD BL as the personal audio equivalent of one of those big, fat pocket knives with a dozen or two different tools. I actually tested all of these inputs and outputs, and they all work as advertised. What's interesting is that the COAX S/PDIF output functions even with the DAC switched off. As expected, there's no signal on the COAX S/PDIF output with PCM material at sampling rates above 192kHz or with DSD. The only thing missing is conversion of the analog input signal to digital on the USB and COAX S/PDIF outputs. :-)



The combination of Power Mode and iEMatch® switches provide, in theory, nine different gain settings; however, iEMatch® is likely intended to be used with Power Mode set to "Eco", so effectively, there are five different gain settings. These are important because both versions of the micro iDSD have volume tracking issues at settings below 9 o'clock. Used together, these switches should enable just about any headphones to operate comfortably at close to the optimal 3 o'clock volume setting.


The sound can be tailored using the X-Bass®, 3D Holographic Sound®, Filter, and Phase switches. I always felt that the effect of the 3D switch was a little too heavy-handed on the original micro iDSD; however, it seems to be more pleasing on the iDSD BL, making it usable even without the X-Bass switch enabled for most music. My understanding is that these switches have a different effect on the RCA line outputs when the preamplifier mode is engaged, providing enhanced stereo separation in the bass. I did not test this for reasons that I'll explain later. Like all of iFi's other DSD-capable DACs, the behavior of the filter switch depends on input format. Normal and minimum phase are digital oversampling filter settings with different cut-off frequencies, and bit-perfect is a non-oversampling setting with no digital filter. The same positions affect the cut-off frequency of the analog filter for DSD. The phase switch is a nice addition, however, although I'm somewhat sensitive to absolute phase in my loudspeaker + room system, I've never been able to identify a difference by inverting phase while listening with headphones.


The light on top of the DAC changes color to indicate the source format. I wish that the micro iDSD models used a color scheme that's more similar to the nano iDSD and micro iDAC2. On the latter, green indicates a CD/DAT sampling frequency while any other color indicates high-rez. This is a useful distinction that's lost with the micro iDSD models which illuminate green for anything at or below 96kHz.


A more significant point against the micro iDSD models relative to their less advanced siblings is the loud POP! that is emitted from both the headphone and RCA outputs when the device is switched on and sometimes when it's switched off and goes in/out of standby mode. I was disappointed when I discovered this issue with the original micro iDSD and even more disappointed to find that it has not been corrected in the iDSD BL. Not only is this POP! somewhat painful if you switch on the DAC while wearing efficient headphones, it precludes the DAC from directly driving power amplifiers and powered monitors. It can be a problem even if great care is taken to ensure that the external amplifiers are always off or muted during DAC power transitions because going into or waking up from standby can also cause an output surge. While not expensive, at the ~$500 USD price-point, I expect an audio product to be more well-behaved. This is why I did not test the preamplifier feature on the iDSD DACs.


My final gripe with the crowd designed micro iDSD concerns the USB type-A input. Oh my gosh is this irritating! The idea is that the DAC will be directly connected to a smartphone or tablet by way of an OTG or camera connection kit cable, making the combination a tidy digital transport+DAC+amp combo for music on-the-go. Even though the type-A input eliminates the need for a short USB cable, this is an awkward and un-pocketable contraption. What's worse, we now have a ~$500 DAC that is incompatible with standard audiophile USB cables like iFi's own Mercury and Gemini, even though the DAC is sufficiently resolving to benefit from using them. We're left using a low-quality adapter or springing for the type-A iPurifier2 (which I did not have on hand for this review) to connect the micro iDSDs to a PC, which for a DAC this size and weight is likely the more common use case. Frustrating! A type-A input would almost make sense on the smaller nano iDSD models, but, in my opinion, it has no place on the micro iDSD. Okay...end of rant!


Moving on from form, features, functionality, and my personal gripes to what you're probably more interested in...how the iDSD BL sounds. In a word, "lively". The BL departs slightly from the signature iFi Audio "house sound", which I would describe as erring on the warm side of neutral. Compared to previous iFi DACs, mid-bass on the BL has a little more punch, and vocals soar with a more open, forward midrange. Highs are, in particular, more extended, airy and pure than the iDAC2.



This new DAC is fast. I mean, crazy fast sounding--if that's even an audio descriptor. Listening to acoustic guitar, you get the sense that the DAC is tracking each string and the associated harmonics with tremendous speed and accuracy. No details are lost. Attacks emerge from the soundstage like a flash of lightening, and decays extend like rolling thunder into a deep black background. The more forward balance of the BL brings alluring presence to vocals but also to strings, snare drums, and brass instruments. The sound is energetic, punchy, and engaging both in the big rig and with headphones.


Switching back to the original micro iDSD, I noted that the presentation is more laid-back and euphoric while still maintaining excellent detail. Soundstage width, depth, and height seem to be slightly greater with the original iDSD while the BL's soundstage is tighter and has a tiny bit more focus. The iDAC2 fits somewhere in the middle with a big, enveloping soundstage and lovely midrange bloom. It falls short relative to the BL only in its treble presentation, which by direct comparison, sounds slightly colored and rolled-off (both DACs using the minimum phase filter setting) vs. BL's pure, airy highs. This difference is most noticeable in acoustic jazz cymbals and hi-hat.




Others have covered in detail what iFi has changed internally to bring about these sonic improvements, so I won't repeat them here except to say that the new Panasonic OS-CON capacitors should receive much of the credit. They are probably also responsible for the longer than normal burn-in time associated with the micro iDSD BL--this thing should finally settle in sonically after about 400-500 hours of playback.


All three of these "micro" sized DSD capable DACs from iFi Audio sound terrific, especially considering their relatively low $350 - $550 USD price range. While there's not a huge difference in sound among them, each clearly has its own personality. If you delight in excavating every last micro detail from your music and listening sessions, the new BL is going to be your favorite by a mile. You might prefer the original iDSD if you prefer to just kick back and veg to soothing music with an enveloping soundstage while occasionally digging on details buried in the mix. If you don't require the portable features, the iDAC2 is incredibly resolving and punchy without being fatiguing.


Your choice among these three may come down to system synergy as well. Listening to the BL with Grado RS2e headphones was an intense experience that could easily become overstimulating and even fatiguing depending on music choice and listening duration. However, the more laid-back Sennheiser HD600s were a delightful match to the BL's liveliness. In the big rig, if your system's balance tends towards forward or analytical, you may find the BL's intensity to be exhausting (perhaps addressable by inserting iFi's micro iTube between the DAC and your amplifier). However, the BL will add a little extra snap to systems with a more relaxed presentation. My big rig system employs room treatments and digital room correction, so the presentation is among the most neutral I have ever heard. As such, I never found the lively, energetic nature of the BL to be fatiguing, and I missed the beautiful, extended treble when I switched back to my beloved iDAC2.


If you own the original micro iDSD, is there enough difference to justify the upgrade? It really depends on your listening priorities and associated equipment. If you have a dedicated audio PC with high-quality media player (JRiver, AMARRA, Audirvana, etc.) and Sennheiser HD600 or better headphones, you'll definitely appreciate the improvements in presence, detail, and speed offered by the BL. If you're mostly driving the DAC with a smartphone and using IEMs, the differences may not be as apparent or easy to appreciate. The BL is a pretty big step up in sound quality and power from the nano iDSD models, but keep in mind that it's also much larger, heavier, and less portable.


The Chord Mojo is now the same price as the micro iDSD BL, so you might be wondering how to choose between these two. I happened to have one on hand for this review, so I did some quick listening comparisons. The difference in sound is nearly as great as the difference in size! Considering form factor alone, the Mojo is the way to go if portable audio is a priority for you. It's small, dense, and ergonomic. It has a pair of headphone jacks for sharing music with a friend without a splitter. While I don't love the mini-USB input, at least it's possible to find both OTG and audiophile grade USB cables with mini-USB plugs, including some from Audioquest. The Mojo's sound is even more laid-back, "British", and warm than the original micro iDSD, so the contrast in presentation between the Mojo and the BL is quite stark. Carefully consider your choice of headphones and associated gear before choosing one over the other. Both are beautifully detailed in their own way, but the BL presents a blacker background with greater dynamic contrast and is my pick between the two for best value for money.



While I do miss some of the benefits of the BL in my system, I'm eagerly looking forward to seeing if iFi will give the iDAC2 the Black Label treatment. If so, that could be a very exciting sounding DAC that will be a welcome addition to an already extremely impressive lineup.


Associated equipment for this review includes:

  • Legacy Audio FOCUS SE loudspeakers
  • Wyred 4 Sound mAMP monoblock amplifiers
  • Emotiva XSP-1 analog preamp
  • Morrow Audio and Straight Wire interconnects, speaker cables, and power cords
  • iFi Audio, XLO, and Wireworld USB cables
  • iFi nano iUSB3.0, micro iUSB2.0, and iPurifier2 USB power and signal conditioners
  • Audio-Technica ATH-M50x, Sennheiser HD600, and Grado RS2e headphones
  • JRiver Media Center v22 running on Windows 10 (with Fidelizer Pro) and Mac OS X


Great review! I love that you used it in your big speaker setup. Your comparisons were very useful and should be of great assistance to anyone considering iFi gear.
Thanks for your contribution! Big thumbs up.
Nice write up! Where did you come up with the "this thing should finally settle in sonically after about 400-500 hours of playback" statistic though on a unit you had for a week?
Fair question...I picked that up during a conversation with Mr. Zero Fidelity himself, Sean Fowler.
I never noticed the pop on power up with my iDSD Micro Silver.  I did notice it with the Black Label.  It isn't that unusual.. I think it indicates lack of a muting relay that would add cost/complexity and is one more item in the signal chain that isn't absolutely necessary.  
Via my Audeze LCD-X headphones, which, for Audeze, are high sensitivity with very easy to drive low impedance, the thunk was merely just an annoyance.  Not anywhere near loud enough for me to be worried about any possible damage to downstream components. 
It may be more inconvenience, but if it truly worries you, keeping your headphones unplugged until after power on is a workable solution.  I will also note this only happens via the headphone output.  No such thunks on the RCA outputs (at least not in fixed mode)
I agree about the increased presence and air.  It is especially welcomed (being done in a quite tasteful amount) in the upper mid lower treble.  Everything has just a bit more life and sparkle.  But I still would not go so far as to characterize the BL as bright.  Actually, as we move on up into the treble the sound is very smooth, sweet, and grain free.  No hint of listener fatigue. 
Back in 2014 I had a discussion with Thorsten Loesch about the USB type A input.  My concern at the time was possible compromise in fidelity when using the Gemini cable.  The extra cable or adapter seemed to be a potential weak spot where any gains achieved via separation of the power and data feeds could be lost.  Thorsten didn't seem to think the difference would be significant, and I am guessing their lab measurements showed little actual difference.  But that is just a guess.  For me the biggest issue I have is the clunkyness of the heavy aluminum termination on the Gemini cable combined with the added length and weight of the iPurifier 2 and/or the required adapter.  All of those combined together plus gravity puts quite a downward strain on the connector.  
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