"I don't know why they didn't bother to record the OBC of My Fair Lady in stereo. I believe Columbia payed the entire budget of the show for the rights to record it, so it surprises me that they didn't spend the extra money for stereo."
In March of 1956, when the OBC of MY FAIR LADY was recorded, the Stereo LP was nowhere near ready for public consumption so there was no real reason to bother with multi-track recording (stereo had been around for years in the movie business and was making for big attraction paired with widescreen pictures at that precise moment but hadn't been grasped for home LP technology yet).
The first experiments with multi-track (in regards to cast albums at Columbia at least) happened later that year with such shows as LIL ABNER being recorded with the orchestra in one track and the vocals in the other (termed binaural at the time though that term I believe has a different meaning today). This technology was still never intended for public consumption but instead to aid the mixing process for more control over audio levels.
The first two cast albums recorded in true stereo came in December 1956 with CANDIDE and BELLS ARE RINGING. However these albums were still released in mono because at that point the stereo LP technology was still being developed (much in the way the soundtracks for the films of Carousel and Oklahoma were released in Mono despite the films featuring full stereo).
By late 1958 stereo LPs had finally been tweaked for public consumption so Columbia started re-releasing the albums they had been recording with multiple tracks the last two years in full stereo, starting (for cast albums at least) with WEST SIDE STORY, recorded in late 1957. There seems to have been no rhyme or reason to the order of re-releases but most of them were released in stereo versions over the next few years (as well as a great many popular mono albums in "duo phonic").
So anyway, while technically it would have been possible to record the MY FAIR LADY OBC in stereo, it just wasn't thought about yet. It really is a pity though, seeing as that album (and the sublime-but-mono MOST HAPPY FELLA) missed out on the technology by just a few months.
Irrelevant tangent finished.
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