To understand why the SACD version is so highly coveted, one must understand DSD technology. Unlike the Pulse Code Modulation (PCM) used in standard CDs, DSD uses a 1-bit sampling process at a much higher frequency.
A Japanese exclusive that uses the same 2021 SACD disc but comes in a specialized 7-inch format package with unique memorabilia replicas. Audio Specifications & Listening Experience
The SACD remained a sought-after collector's item, leading to further exclusive pressings.