This will be another one of my stream of consciousness deals as there's just too much to cover. This is the best way for me to let you guys know about as many aspects of the "Micro BL" as possible. Feel free to ask pointed questions. The iFi Micro iDSD BL could be the finest transportable all-in-one amp/DAC unit I have heard. It might be interesting to compare to the Chord Hugo 2 under more controlled circumstances (blind and in a home setting) however; but that may need to wait. Or maybe not, since the Hugo 2 at $2500 is meant for people who's parents in a totally different wealth bracket. For what it's worth, I didn't care for the Hugo 2. However to be fair, I may have judged it based on performance to cost, or I could have had the the wrong filter settings that did not suit my preferences. Here I've been comparing the Micro BL to the modest Schiit Hel in the past week. It's always good to have a reference. The sound of the Micro BL doesn't seem that totally far off from the Hel. I do prefer the Micro BL's sound slightly more. The Micro BL's sound seems to a departure from the Nano BL reviewed here: https://www.superbestaudiofriends.o...ds-el-dac-ifi-nano-bl.6313/page-2#post-208350). Unfortunately, the Nano BL got lost by USPS, so few SBAF members could ever experience it on the loaner program. The Micro BL can "slay slayer" so to speak more than both the Nano BL and Hel. Of these three AIOs, the Nano BL can be said to be the most relaxed or laid-back sounding, both in tonal presentation and attack. The Hel sounds more even in tone, neutral like the Micro BL. However, the Hel still has hints of the AKM AK4490's "Velvet" sound, where some listeners have complained about it hitting has hard as a wet noodle. The Micro BL relies on a x2 mono TI PCM1793 chip deal. While the Hel's AK4490 is AKM's latest and greatest, the PCM1793 has been around for a while. I figure iFi doubled them up to get better perceived resolution and linearity (THD) so they could compete with today's latest designs. I am impressed that iFi designers have stuck with an older part, and did everything they could to wring as much performance out of it. All too often we have found that newer isn't necessarily better. I do think the Hel just nicks the Micro in terms of plankton, or reproduction of low-level information. Not unexpected as this is one of the "Velvet" sound AKM's sound suits. But it's not really enough to make a difference considering the so many other aspects of the Micro which I prefer. The attacks hit hard and aren't as soft like on the Hel. This is evident from bass drum kicks, finger snaps, etc. from every track on Michael Jackon's Bad (Special Edition). There's more solidity, a more tactile sense, coming from the Micro BL. In addition, the Hel also seems a have bit murkiness which makes textures from bass instruments less evident - more smeared. I'm blaming the AKM DAC portion of the Hel here - it might be interesting to confirm by running an outboard DAC. A possible downside I can see with the Micro BL's presentation is that it can be unrelenting with certain headphones or recordings. At first, I thought the BL was glarey and difficult in the highs with too many recordings, but it turned out that I had incorrectly set the filter to minimum phase. I have always disliked minimum phase filters. There has been discussion on minimum phase filter's here: https://www.superbestaudiofriends.o...d-post-effin-ringing-and-shit-like-that.2627/. They might be good for gaming because of low-latency, but for musical enjoyment, I'd rather avoid them. Setting the filter to linear phase or "Bitperfect" (and running from the battery - more on this later) makes the high end so much smoother. Remind me to post FR and impulse response measurements so we can see what's going on here. Also note the IEmatch (for people with IEMs). to be continued.