[General Accessories] vectron:
Pair-up and Comparison.

I think this “pair-up” section is the most important in describing the sound of Micro because it gives you a better perspective with a relative comparison of how other headphones sound with Micro and how it compares to a selection of other DACs/amps. In this test I used Micro connected to my laptop, and selected ES60, PM-3, EL-8C, and U12 for listening comparison with Micro iDSD, Nano iDSD, Schiit FULLA, Cozoy Aegis, and GeekOut GO450. Below are my listening notes with each pair of headphones.

Westone ES60 CIEM.

- w/Micro - hissing is under control with a gain switch (of IEMatch), smooth detailed sound, punchy extended tight bass, smooth detailed mids, well defined extended treble, smooth analog detailed tonality, and excellent transparency and layering/separation of instruments.

- w/Nano – more background hiss (can’t take advantage of gain switch), the sound is not as smooth as Micro, still a punchy extended bass, but not as articulate in comparison to Micro, mids are revealing and detailed, but not as smooth as Micro, treble is very similar and so does soundstage expansion.

- w/FULLA - a lot of hiss and distracting EMI crackle, soundstage is a little wider in comparison to Micro, the sound is bright and detailed, bass is not as tight and sub-bass is extended but not as deep as with Micro, but still, the bass is fast and punchy, mids are brighter in comparison, a little more upfront though not as smooth, also treble is brighter and with more crunch.

- w/AEGIS - a lot of hiss, have to use a minimum volume setting (too much default gain, not good with sensitive multi-BA monitors), and I hear a lot of background noise. The sound is balanced, detailed, bright, with a punchy extended tight bass, detailed revealing mids, and a well defined extended treble.

- w/GO450 - using 47 ohm output I hear less hissing/noise - but sound is dull and not as detailed, when switching to 0.47 ohm out – serious hissing, but sound is more detailed. With the later one, I hear a balanced detailed revealing sound, punchy extended tight bass, detailed revealing mids, and a well defined extended treble.

Oppo PM-3 planar magnetic full size.

- w/Micro – I hear a smooth detailed sound, punchy bass (but not as fast), smooth clear mids, nice smooth clear treble which is not as airy or extended. In this pair up mids sound very natural, probably the best PM-3 pair up I heard to date. I was a bit surprised since PM-3 is warm smooth to begin with, but Micro made them shine, especially with 3D switch on.

- w/Nano – it was a bit short on power to drive PM-3 to their full potential, definitely a bit of a stretch for Nano, the sound was not as smooth, less revealing, not as transparent or layered, it was clear but not as detailed, and mids were a little less natural.

- w/FULLA - nice deep punchy bass, tight and articulate, but mids didn’t sound as natural, and the sound was not as transparent or layered, a bit flat, though treble was clear and well defined – the star of his pair up.

- w/AEGIS - nice deep articulate bass, but mids sound a bit off being a bit bright and unnatural, nice extended treble with a good airiness.

- w/GO450 - great bass impact, bright detailed mids, nicely extended treble, and a decent transparency.

Audeze EL-8C planar magnetic full size.

- w/Micro - bright revealing fast sound, has a slight metallic sheen, punchy fast bass, bright analytical mids, airy extended treble. Mids are not as organic or natural. I was a bit surprised, but didn’t like this pair up.

- w/Nano - bright revealing sound, very noticeable metallic sheen, punchy fast bass but not as much sub-bass, bright analytical mids though could be a bit harsh with some songs, crisp extended airy treble. Mids could be a lot more smoother.

- w/FULLA - bright revealing fast sound, fast punchy bass, bright analytical mids, airy extended treble, still traces of metallic sheen, and sounds is not as natural.

- w/AEGIS - bright revealing sound, metallic sheen, too vivid, fast punchy bass with a noticeable sub-bass extension, mids are bright revealing but slightly harsh, treble is bright crisp airy.

- w/GO450 - bright revealing sound, articulate fast tight bass, mids are a bit shouty, bright, revealing, not as metallic as with other pair ups. Treble is crisp and extended. This pair up yields a touch less of metallic sheen.

64 Audio ADEL U12 IEM.

- w/Micro - zero hiss (in Eco gain), smooth detailed sound, fast deep articulate low end with a nice punch, smooth detailed mids, smooth clean well defined treble. Nicely expanded soundstage, even works with 3D switch.

- w/Nano - a little bit of hiss, smooth detailed sound, deep articulate low end with a fast punch and a nice sub-bass extension, but bass is not as tight as with Micro. Mids are smooth and detailed, but not as detailed as Micro, and I also hear a clean treble though not as extended. Micro feels like it has a little better retrieval of details with U12.

- w/FULLA - a little hiss, sound is a bit congested with overpowering low end, and not as transparent or detailed. But overall tonality is warm and you can hear a tight low end punch.

- w/AEGIS - too much power for these IEMs, too much noise/hiss, can't even play it from laptop, this DAC/amp is not good for majority of sensitive IEMs.

- w/GO450 - (0.47 ohm output), smooth warm sound, low end is not as tight but still has a good sub-bass extension, warm smooth clear mids but not as detailed, clear treble with some roll off.

With some other headphones:

- Micro w/T5p.2 - bright revealing detailed sound, not as much body or sub-bass, fast mid-bass punch, lean lower mids, bright analytical upper mids, a bit harsh with some traces of sibilance, bright crisp, airy treble.

- Micro w/R70x - excellent pair up with a very natural detailed sound, articulate punchy mid-bass, lean detailed mids with organic sound quality and excellent retrieval of details, extended crisp treble, excellent soundstage.

- Micro w/MSR7 - great pair up with a clear detailed sound, not too bright, punchy extended bass, nicely balanced mids (not too full or too lean), mids are definitely not as bright as with some other sources, and crisp detailed treble. Has a great soundstage expansion as well. Overall sound is well balanced and detailed.

- Micro w/DN2kJ - good pair up, upper frequencies are under control, but still a bit bright and with a more mid-forward signature. Bass quality is good, but not as much quantity, sound sig is more J shaped.

Conclusion.

When it comes to my casual headphone listening at home, I found that any USB DAC will do because they all improve the sound of my aging ThinkPad T430s laptop. But it was never as enjoyable until I switched to Micro iDSD and now can't even think about using anything else. Micro's smooth analog detailed sound characteristics just works with any pair of headphones regardless of their sound signature. Micro's design has an amazing flexibility to accommodate any audio setup, portable or desktop. And due to its ability to play everything up to and including Octa-speed DSD512, instead of enjoying my usual selection of EDM tracks, now I'm searching on-line to find exotic DSD128, DSD256, and DSD512 classical orchestra performances. Did I become a fan of Mozart and Chopin music renditions? Not really, but I'm fascinated with being able to play 1.5GB DSD256 audio files from my laptop without skipping a beat or a string.

I'm already anticipating questions after the review asking me how does Micro iDSD compares to Chord products, such as Mojo or Hugo. I can't answer that because I never tested any Chord products. That would certainly make an interesting comparison, especially since Mojo is in a same price category. But until then, Micro iDSD will have a solid place at the top of my USB DAC/amp food chain because no other product I've tested in this category comes close to its performance and sound quality. My only wish is for iFi design team to be able to pack performance and sound quality of Micro iDSD into Nano iDSD footprint, turning this transportable into fully portable.