Strange frequency analysis of 24/96 file

[carbo56]

Here is some frequency analysis of recordings that I did with Vinyl Studio in 24/96 resolution.  They look strange, as it comes down to 24kHz and then rises in almost a mirror image.   The lineage is:  Music Hall PA2.2->USB->MacBookPro->VinylStudio.  Other recordings from different sources look similar to this.

What does this indicate about the ADC in the Music Hall PA2.2 and/or my configuration? 

Thanks for the help.

[Paul Sanders (AlpineSoft)]

Yes, it certainly looks to me like an artefact of the ADC.  It shouldn't, in my opinion, be generating a frequency distribution like this.

The sharp dropoff around 20 kHz is normal, since most analog sources tail off around there.  The rest makes no sense at all.  I would ask Music Hall about it:

https://musichallaudio.com/contact-music-hall-audio/

I assume you haven't applied any filtering in VinylStudio.  If you have, I would remove it and check again, just to be sure.