And yeah, it is possible to download and play 5.1 mixes in without hard media, though AFAIK there aren't two many records available like that. But I have one album with a 5.1 mix that was released as an USB stick, and also I managed to come across someone sharing files of all Daft Punk albums as (probably unofficial) 5.1 mixes. So you can just put the files on a USB stick, stick it in your player/amp, and if it supports the file type, they will play in surround.
― Tuomas, Thursday, 28 January 2021 16:48 (three years ago) link