5.1 music on YouTube (at last) xD
Yes, 'Real 5.1', YouTube now actually supports multichannel audio on certain devices, TV's, Roku sticks, Amazon Fire TV devices, Android TV, Chromecast (UK Sky TV boxes) Apple TV etc. No browser support as yet, so if you are running Windows, Mac, Linux etc, you will only get a stereo representation (downmix) of the 5.1 mixes.
There is a workaround for PC that lets you stream from YouTube via a program called PotPlayer available for free on Windows 11 here
potplayer.daum.net/
I try hard to get the UpMixes and demucs mixes right and sounding good, most of the time I feel 'they could be lots better', but sometimes I get them 'right', or what I feel is 'right', it's a relative and subjective term, usually. Sometimes the original mixes are not 'right', a lot of the time when they are not 'right' they seem to me to be lacking in bottom end and/or width, and don't translate well via YouTube. Explanations are a 'mindfield' (I know).