Here’s another video review on the "GaN Technology" Technics SU-R1000 vs the NAD Master Series M33 (which uses the Hypex N-Core class-D modules)
Seems they both prefer the Technics SU-R1000 in the upper mids highs range.
This "could be" because of the 1.5mhz (3 x higher) switching frequency it’s said they use like in their flagship SE-R1 poweramp.
Which takes class-d’s normally used 400-600khz switching frequencies output filter’s negative effects well away (by 3 x also) from the audio band, without having to use any other "alternative" fixes to cure the problem that "could" also have their own detrimental effects.
https://www.youtube.com/watch?v=x2rzllFT6S4
Cheers George