This is really interesting. It is a film on the making of a RCA Living Stereo recording, 1956, Tchaikovsky’s Romeo & Juliet - Fantasy Charles Munch the BSO.
It begins with the recording in Symphony Hall. You can see the placement of the microphones and the tape recorders in the control room. It even shows where all those priceless tapes are stored. It includes much detail in the actual disc making process. Folks who have the vinyl versions of these records should find this part especially interesting.
It is remarkable that such wonderful recordings were made with so simple equipment and so little of it.
I also found the following article interesting It is famed RCA recording pair Jack Pfeiffer and Lewis Layton experience of recording Artur Rubinstein