The default numbers for 2nd and 3rd harmonics were calibrated prior to the unit being sent to me to correspond to results on the Audio Precision SYS27XX with a -0.5dBFS signal. You can also change which filter setting is applied to the ADC channels; "Linear phase apo" and "Linear phase fast" both worked well in my testing. With a device like your Cosmos range, an amateur, if spending enough time, may achieve similar individual results, or even better. The 2.5mm TRRS input is so close to a screw holding the front panel in place that I had to remove the offending screw. The remaining three screws will hold the panel in place just as well however. You are right, my table was not readable (wrong labelling, just modified - indication of switch positions (6.7V |10V) was unnecessary). Hence this description:

Of course, remember to keep those cables (especially unbalanced ones) nice and short and the APU/ADC measurement system away from electrically noisy devices like powerful computers when testing. as an example, I see some clue of IMD at intermediate level in mono mode. To be true, this is because noise is so low, so not really a concern) As you can see by comparing the 2 measurements above (the second, with 122dB SINAD, being done with the E1DA ADC), this may limit the output level of the DAC. Regarding the grading, each Cosmos ADC unit is individually calibrated for the minimal distortions at level -0.5dbfs 1kHz with the typical THD <0.00003% or to say shorter .3-.2PPM. The typical level of 2nd, 3rd, and other harmonics between -135.. -145db for all grades from A to C. Grades are only about the noise, and each unit has a grade mark on the left side of the front panel. In most cases, SNR/Dynamic_Range in the MONO mode is within 127+/-1db(A) it is grade-B Cosmos ADC. Less than 126db(A) means grade-C, from 128db(A) and better grade-A, 129db(A) and better grade-0(very rare grade, and probably redundant, just in case). The MONO mode improves the SNR/DR for 3db, so a grade-A unit typically has SNR 125db(A) in STEREO mode. MONO/STEREO modes are switchable by the UAC2 volume commands, for example, if your Windows volume slider position is less than 50%(0 to 49%) the device works as 2 channel ADC, if more than 50% it is a MONO ADC with summed Left+Right inputs mapped on the Left channel(Right input is always mapped to the Right channel). In the MONO mode, both channels need to be tied together L+ to R+, L- to L-. Damage due to user negligence, accidents, disassembly, waterlog, misuse, abuse, alterations or vandalism.The bottom side of the device also conceals a DIP switch attenuator with 8 sensitivity levels, from 1.7V to 10V. Each sensitivity value has a different input impedance. To connect Cosmos ADC to the Load board we prepared the XLR probe cable. It is a 1/2m short a decent quality shielded cable(a lot of copper!) with two hook-clamps(red-POS and white-NEG Inputs) and one crocodile-clamp(GND) on the DUT end.

You will need to install the ComTrue 7601 USB Bridge driver for ASIO; I used the current version 6.0.1.20210429. I had no problems with the ASIO driver in WaveSpectra. But ran into various software complaints in ARTA, and Room EQ Wizard. I eventually settled on ASIO4All in REW which worked fine up to 192kHz. Any item returned must be complete with all accessories, hardware, manuals, or instructions, and in the same "new" condition as when it was when shipped to you. Please send us photos or videos of it. it is a MONO ADC with summed Left+Right inputs mapped on the Left channel (Right input is always mapped to the Right channel). In the MONO mode, both channels need to be tied together L+ to R+, L- to R-." Premium Audio Components including OPA1612 OPAMPs, Susumu & Viking Resistors, Murata & Samsung COG Capacitors, Taiwanese connectors, and switches. The very last release of REW, v5.20.9, even allows to display the frequency range taken into account for the fundamental. That's genious !)Like when mismatching impedance of amps with speakers/headphones, you will see a voltage "droop" if you connect high impedance devices into this ADC relative to the impedance table above. Yeah, this will have an effect on the results; the pragmatic question is how big of an impact this will have and that I suspect will be an interplay between the ADC and your test device and its level of performance. I'll certainly monitor this in the days ahead as I try out different gear and obviously I will still have my RME ADC to compare. ADC stands for Analog To Digital Converter. Since computers only process digital information, they require digital input. An ADC, such as the Cosmos ADC here converts an analog input into a digital signal to process on the computer system. It is widely used by professional reviewers and audio enthusiasts to measure their audio gears. High-Performance ES9822Pro ADC Chip:- LEDs on the front panel work as a "Signal" indication - green if the STEREO mode and the input > -30dbfs, or blue in the MONO mode. A "Clipping" red-LEDs indicate that the input level reached 0dbfs. i.e. 80s style as I believe ;) is below 1nV; the flat noise spectrum of the Cosmos ADC means that picovolt level signals can potentially be measured at any audio frequency with sufficient FFT lengths, provided they are narrow enough bandwidth (4M FFT length means ~0.01Hz bins).

While this unit is one of his builds for external testers, I suspect that it should be much the same as the final product when available hopefully later this month. Obviously there could still be some changes with the final production release. tied to the APU's preamp input! Please wait for at least 10s after the phantom power is Off, to safely plug/unplug anything to the Preamp input. use not following the ‘User Guide’ or any additional safety, use, or warnings included in the product materials.From a technical point of view, I understand that the high level input is on an extra connector because in case that would be on the XLR inputs and the attenuation settings were wrong, the ADC could be damaged. With the compact chassis size there is probably no better solution. Ladies and gents, fellow hi-fi audiophiles - when it comes to achieving " Good Enough" quality for human hearing, I hope everyone appreciates that we're assuredlybeyond that at this point in the history of audiophile DACs at very reasonable price points! If you're wondering about the E1DA name, as explained by Ivan, it comes from the pronunciation of "Ivan" as sounding like "E1" in Russian as opposed to the Americanized "Eye-Ven". "DA" as in "dah" ("да", "yes") - so it means "Ivan Yes".] Any item returned incomplete or with physical damage such as scratches etc., excessive signs of use, or abuse will not be accepted for return. 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.