What does it mean to a non-lay person?
Any number of things. Is it clock related, is it Multi Bit glitch related, is it a DS DAC with low order modulator, is it less than ideal DF artifacts.... and so on.
And why would you care about MHz region when you have a bunch of noise parked just above 24 kHz in DSD content I showed?
WRT DSD OOB noise:
a/ DSD64 (2.8224MHz) does inherently have OOB noise, depends on the order of noise shaping used. Any properly designed AC's that play native DSD will have an FIR LPF which is inherent in the DAC OP architecture. Check the data sheets. After that follows an analog LPF of 3rd or 4th order.
What's left will be too low to harm any electronics or speaker.
b/ Most people these days are streaming or downloading DSD128 or DSD256 which pushes that noise even lower.
c/ If you are seeing huge amounts of noise at near 24kHz in those recordings it might be worth inquiring what ADC they are using. This may even be an artifact from the original analog tape recordings. Even DSD64, depending on noise shaping used should be -100dB at 30kHz and -60dB at 100kHz. Factor in the above mentioned DAC LPF's and OOB noise will not be an issue.
With available download speeds and cheap compatible DACs these days, DSD playback up to 256x is now a reality for people to have fun and explore. Let them decide whether they like it or not. What's the downside?
TCD