De-mix Technology - Abbey Road Studios
Our De-mix process opens up access to previously locked recordings, allowing audio engineers to craft new mixes and masters. Creating a superior listening experience for music fans, our De-mix process reinvigorates catalogue and breathes new life into forgotten tracks or bootlegs.
Once separation is complete, our engineers can begin to remix or remaster the original base recording...to stereo
AFAIK, mono versions of albums ended in ~1968 (mono mixes were done separately, they weren't the stereo mix combined to mono)
Although it's the same song (not an alternate take, for example), it would sound noticeably different in "stereo" than it did in mono.
Tech hasn't allowed this type of thing until very recently, I don't know how many pre-1969 songs are typically played on the radio, would radio likely switch over to using the "stereo" (de-mixed mono) version or stay with the mono version?
Kirk Bayne