Bone Records LPs


Has any one here ever listen to Bone Records? Just curious how does it sound. Your discretion is advised...most of you guys here will be shocked :))) ..... the term “Bone Record” belongs to bootleg lines of records born in Soviet Union late 50’s, those records was copied from original LPs which was not available in general to vinyl sheets of used X-ray images that’s why they was called Bone. In 60’s production of Bone Records reached mass scale. Check it out-http://amp.theguardian.com/music/2015/jan/29/bone-music-soviet-bootleg-records-pressed-on-xrays

https://www.amusingplanet.com/2019/02/bone-records-soviet-era-bootlegged.html?m=1
surfmuz
Every pirated LP that I ever heard sounded worse than "junk", unlistenable.  Direct to trash.
Curious, how actual process of copying was performed. Was it some form of cutting machine or something.