Got a S8 to try for myself, I realize the Sonata HD Pro is the same DAC design for cheaper, but I like the look of the S8 better and it includes with an OTG Micro-Lightning cable for my iPhone, which can cost 15-20 dollars on its own, so $75 next day shipped from Amazon didn't seem like a bad deal. Included lightning cable is of a different build/make and noticeably better quality than the other stock cables, not sure if they ran out and sourced a different cable in short notice, or if it's an upgraded cable following complaints of the stock lightning cable failing (seems like they'd replace all of the cables and not just lightning if this was the case), but it's very supple, the sheathing is a translucent smokey soft plastic and you can see the bright copper wiring through it, very similar build to the Campfire/ALO smokey litz cable, but with thicker wire. We'll see how long it lasts, I'm expecting the worst, but it does seem pretty solid and with care, should last a while. Plugs and plays perfect on my iPhone, and the sound is very great and top notch. With my Campfire Ara, it noticeably thickens the bass and increases slam/impact, so it does seem to have a very low output impedance. The hardware volume control is very useful for extremely sensitive IEMs like Ara, because even though the steps aren't the largest, the independent control of the DAC and software volume can better fine tune the sound to something that's totally noise/hiss free while still giving plenty of dynamic range, can't overstate it enough how much a pleasure it is to have a zero noise, black background yet still have a highly dynamic sound on the Ara, which like most CFA's IEMs pick up noise like the devil. Layering and separation are top notch, don't feel the S8 has any issue rendering busy passages while still being able to pick out all individual voices/instruments, low level details are picked up effortlessly and contributes to its engaging and realistic "live" sound. The overall tonal balance to my ears is neutral to slightly warm, very organic and natural, doesn't sound "digital", sibilance and other loud HF peaks are nicely rounded out so they still have impact but are not overly sharp or grating. Overall stage is slightly less spherical and enveloping than something like the Helm Bolt, think it has a higher OI which makes Ara a little more airy and thinner and contributes to that, but it is still impressively wide with good depth and height, projecting sounds just outside my head/ears with highly accurate imaging/placement. All in all, great sound and even better noise performance, never had a DAC/dongle with such a black background with <10ohm IEMs while retaining high dynamic range and smooth fidelity. Definitely a keeper! Got it for the high marks, keeping it for the great sound. If the lightning cable ends up holding out and working for a while, this is absolutely a home run for me in terms of a perfect dongle, considering its non existent hiss/noise, high dynamic range, and overall fidelity and smoothness.