This and That:
What you get, next to the DAC itself and a neat little manual, are three USB cables (micro USB, USB-C, USB-A). What's lacking is an Apple-specific cable, even though the ZuperDAC-S works with Apple devices (but you need to use Apple's Camera Connection Kit).
Build Quality is good. I'd like to see the volume buttons labelled though.
The three cables have got woven insulation but are stiffer than what one would probably want for fully portable use. They’re easy to replace though since there is no permanently attached cable but a universally usable micro USB socket.
Drivers need to be installed on a Windows computer for the ZuperDAC-S to work with it.
When in use, the ZuperDAC-S will warm up a bit, but never reaches temperatures close to be considered “hot”.
Volume Control:
Volume is controlled digitally, so there is no channel imbalance even at low settings, and there are 16 steps in total. The last volume setting isn’t only stored and remembered after plugging the ZuperDAC-S into another device, but the volume control works also independently from the host, which means that one can use the DAC’s volume control if one's host doesn’t allow any volume adjustment, or if the host’s volume control isn’t as precise as you would like to.
For this I really applaud Zorloo – volume control is super precise with Android devices as a result (, albeit not exactly with my Windows 7 laptop where I cannot use the built-in Windows volume but have to use the ZuperDAC-S’s 16 built-in volume steps).
Sound:
Frequency Response:
Let’s see how the Zorloo performs in this regard:
As it could be expected, the raw and unloaded frequency response is perfectly flat and therefore just the way it should be.
Output Impedance:
Zorloo states an output impedance of less than 2 Ohms, which might already lead to some skewing of the frequency response in combination with some critical multi-BA in-ears.
This is what the ZuperDAC-S puts out when connecting a critical, low impedance multi-driver in-ear to its single-ended output:
The connected load was my Ultimate Ears Triple.Fi 10 that shows quite diva-esque behaviour if the output impedance isn't super low.
The measured deviation in combination with the Zorloo indicates an output impedance that can be calculated to be around 1.6 Ohms, which backs up Zorloo’s own specs, so it's neither super low nor super high.
Hiss:
Using the Zorloo with very sensitive in-ears such as my Shure SE846 or the Ostry KC06A, I can report that I am very delighted since even with those very hiss-revealing in-ears, there is no audible hiss coming from the ZuperDAC-S, no matter what volume setting is chosen.
Subjective Sound Perception:
The ZuperDAC-S sounds similar to its predecessor to me, except for being fully hiss-free with super sensitive in-ears and except for having the lower output impedance.
Using sensitive, well-resolving in-ears, it is no surprise that, based on the measurements that don't show any flaws, the DAC sounds just as tight, transparent and clean as an audio device that doesn't have any deficiencies should sound.
Conclusion:
Excellent hiss performance, average output impedance (neither very good nor bad), handy volume control (works independently from Android host's volume control for more volume step precision; however disables Windows' internal volume control on my Windows 7 laptop).