@whart said it all!
By the way, some of the MoFi LP’s made in the past 15 years WERE "cut" (the lacquer) from analog tapes (presumably a "production"/aka "safety" copy---usually 1/4" 15 IPS---of the 2/ch mix master, though some original studio master tapes are made available by some companies, particularly WEA), amongst them a couple of Ry Cooder albums, as well as the debut by David Crosby.
For those who don’t already know, the Analogue Productions Kind Of Blue was made using the metal parts made by Bernie Grundman back in 1997 (for Classic Records), using the actual 3 channel master tape fed directly into Grundman’s mixing console, no intermediary 2/ch tape made or used! Grundman was the one who discovered the original master mix---from which all releases of Kind Of Blue had been made---was made with the songs on one side of the LP having been recorded in the studio with the 3-track machine running at the wrong speed, causing the music to be heard slightly off pitch and tempo. He of course corrected that in his mastering.
In his mastering of Tea For The Tillerman for AP, Grundman discovered the original release had been mastered assuming Dolby noise reduction had been employed in the recording. It had not; with Dolby engaged in playback, the recording was subjected to a considerable degree of high frequency roll-off, resulting in the sound of Cat Stevens’ plastic-bodied Ovation acoustic guitar/guitar strings/etc. to be drastically changed, as well as that of the drumset cymbals and any and all other high frequency sound producers (the upper harmonics of the acoustic bass strings, etc.). The AP reissue of TFTT was the first that sounded anywhere close to that of the master tape. Thank God for Bernie Grundman!