"Bone records" (https://www.npr.org/2016/01/09/462289635/bones-and-grooves-weird-secret-history-of-soviet-x-ray-music https://www.npr.org/2016/01/09/462289635/b

"Bone records" (https://www.npr.org/2016/01/09/462289635/bones-and-grooves-weird-secret-history-of-soviet-x-ray-music https://www.npr.org/2016/01/09/462289635/bones-and-grooves-w...). For black market uses, the consumers was probably willing to bear dreadful audio quality. For a modern aficionado, the quality must be good enough to give some justification for the endeavor.