Hi Matthew,
Sorry, fully disagree. And let me be blunt as well.
You challenge and undermine a whole, so called Hi-Res audio music range, where files have 96kHz or 192kHz sampling rate or even more when talking about DSD - these in result would be seen in DAW spectrum as a half of above respectively.
You try to neglect a whole rapidly growing branch of music files business that tries to get digitally as close to natural analog transport as possible. And You try to neglect tons of listening test valuations, validations - comparisons of just mere CD quality with Hi-Res audio files. These experiences clearly show huge advantage Hi-Res audio files over CD range that cuts of at 20kHz.
I don't think this is smart if you do answer this way being a representative of Presonus company - sorry I can't see whether you answer as private or not. Because this way you would neglect even what Presonus does with their hardware.
I own AudioBox iTwo interface which has sampling rate 96kHz (48khz in DAW) and the newest interfaces boast of a range 192kHz (96kHz in DAW)
So, why bother with so high sampling rate when you cannot hear the difference over 20kHz ?
Talking about physics and and our hearing:
You probably forgot (hope you have this knowledge) about "beat tones" in acoustics: https://en.wikipedia.org/wiki/Beat_(acoustics)#/media/File:WaveInterference.gif
or wider in Wiki:
https://en.wikipedia.org/wiki/Beat_(acoustics)
where, say, at least two waves with close frequency overlayed give a sum that has amplitude frequency spectrum several or even several dozen times lower than basic waves.
So if we have two waves of frequency even much higher than 20kHz, say 96kHz, than this "beat tones" phenomenon would result in audible frequency - the sum of these basic, below 20kHz.
And this is what is heard as air around instruments, voices, also clarity, transparency of a music sound, lesser harshness at high end, etc.
And because music sound assembles mainly harmonic waves this "beat tones" phenomenon is very apparent - from beyond 20kHz into audible range.
Talking about noise:
I have another EQ plugins that have a spectrum meter with the range as high as file has.
And I noticed that some hi-res files have noise spectrum ranging from 30 to 50kHz at level about -30dB tp -90dB
If you are interested I can attach file or paste screenshots.
So the questions remain:
1. Where does it come from? What is the source? what to replace or what component to improve?
2. Why I cannot see this noise in the spectrum of my music listened, mixed or recorded in Presonus DAW?
3. Does it have any influence on the D/A conversion ?
The answer on question 3 is obvious and is YES, it has great impact on decoded music file quality.
Talking about digital audio there is the major fight against any noise, like from USB power supply, static grounding loop, etc.
and therefore devices that fight with this kind of noise are pretty costly.
Greetings, Roberto