Almost perfect white noise spectrum, with only a bit of low frequency rise. The chart starts at 2Hz so performance is better than it looks at first glance. With these settings the white noise is -187dBFS at 1kHz.

As you can see, Windows will list up to stereo 32/384 PCM capabilities. I didn't test this with Mac or Linux which I believe should work fine. As you can imagine with up to +60dB gain, be careful with feeding the APU too high of an input signal.Keep the pre-amp input below 3.5Vrmsand the notch filter input below 10Vrms. In the case of severe overvoltage with excess current, there is TVS protection in the pre-amp section but this could burn out a small 10Ω surface mount 0603 resistor which acts like a fuse and would need to be replaced. ( More tech details from Ivan here.) I see that L7AudioLab has posted on the Cosmos APUas well recently. Looks like his measurements of the Topping D90SEshows even higher SINAD results using the APU's 1kHz notch filter than even with the Audio Precision APx555; he got a result way up at SINAD 126-127! Alas, I have sold my D90SE so am unable to run such a test at this moment. This warranty extends only to personal use & does not extend to any product that has been used for commercial use, rental use, or use that is not intended. There are no warranties other than expressly set forth herein. If you can afford it, the RME, especially with the APU when required, remains the top choice for measurerments, IMO.

Apple cancelled this, now what?

You are right, my table was not readable (wrong labelling, just modified - indication of switch positions (6.7V |10V) was unnecessary). Hence this description:

On top of that, the addition of +48 V phantom power will make the Cosmos APU, chained with any ADC, in my case it’ll be Cosmos ADC, a top notch combo for any compatible condenser or dynamic microphone out there. Basically, there haven’t been manufactured yet an audio interface having a better performance than the above combo, and I’m referring now strictly to THD+N and dynamics. In terms of gain, the +60 dB pre-amplification will match the max. gain of my Motu M4 and will even outperform Focusrite Clarret’s +57 dB of gain, meaning that Cosmos APU + ADC combo can be successfully used with low-sensitivity mics like AKG D5 and Sure SM7B. That's 17 dB lower for the 3rd harmonic. That's even better than what Amir measured. (I must have a better test set-up ) In the picture above, we can see that the main inputs for the ADC are the dual balanced XLR connectors. Notice that the markings indicate that they can have input levels up to 10Vrms (+22dBu). The input level can be adjusted to optimize the dynamic range when you're measuring devices of lower voltage. You adjust this with some DIP switches at the bottom of the unit (I have been told that these are high-quality gold plated switches, guaranteed for minimum 1000 cycles):

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The calibration is performed at the particular ambient temperature 27C, if your environment is seriously colder/hotter the THD performance is not guaranteed. Every time the unit needs to be warmed up during 15-20min before use.

Each step has been able to get me lower noise (higher dynamic range), and in concert better jitter performance for measurements of higher resolution devices. Accidents, abuse, misuse, improper installation, problems with electrical power, acts of third parties.The result was so disappointing that I didn't even try to do a loop measurement with the Topping E70 that I bought a month ago.