Wow ! I had no idea these archives or old publications even existed. Thanks !
I clicked my way to the one mentioned, but unfortunately that one particular page with the info. you were talking about was poorly scanned and just barely readable. Unfortunate because it also has an ad for Magnecord, showing early models. (pg. 9)
http://www.americanradiohistory.com/Archive-Tape-Recording/50s/Tape-Recording-1953-11-12.pdfIf you ever do find one of those early 15 ips. binaural releases I would love to hear it.
It is interesting that there is a Shure ad a few pages earlier (pg. 4) that is essentially the same photograph of the Fine Arts Quartet, promoting the use of their Sonodyne 51 microphone to record it. I really hope not, with at least that mic, as it was not very good even for the mid 50s microphone state of the art. My catalogs list the frequency response spec. as 60-10,000 with no further qualification. It was not their best mic even at the time, with the now so called "Elvis mic" having a wider stated response. Ironically it is also the microphone The 78 Project is using with their traveling Presto lathe for nostalgia, to record their discs on location. It is probably just a bit wider response than the Presto disc cutting head.
Ah, just read the Shure ad again. They stated they were using it to record their own _rehearsals_. :-)
One more mod. Apparently not all PDF readers do a good job with their files, particularly one used in Firefox.
They suggest not using that one, which I was. Certain fonts below a particular size are not clear.