Wednesday, August 31, 2011

A Note on Broadcasting History

Recently, we featured some Crusade for Freedom programs on our YouTube channel. What you don’t know is this effort fits in nicely with my last blog post. You see, the disc both programs came from is a type that would only be transferred due to a research request. When you’re emailed a WorldCat record from a former Radio Free Europe/Radio Liberty (RFE/RL) security director about a Crusade for Freedom program, however, things change.

So why did it take an inquiry by an external party for us to digitize and republish those programs?

Those programs were on a sixteen-inch-diameter vinyl disc. First, vinyl discs of any size are relatively stable because they’re generally a single piece of plastic and, due to a niche market that prefers listening to records instead of CDs and mp3s, turntable equipment is easily obtained. (Myself, I prefer SACDs, but that’s an even smaller niche.) Second, although labels tell us a lot, they don’t tell us everything; thus, this disc had to wait while we worked on less stable recordings. We have some hundred similar sixteen-inch vinyl discs, including speeches by Robert Taft in the America First Committee records and collections sporting great names.

If you’re wondering how these sixteen-inch-diameter discs relate to the LPs audiophiles are likely familiar, they’re directly related.

In the days before magnetic tape (1930s to early 1950s), radio syndication was done using these discs. The producer would cut a lacquer disc of the program, and moldings made from that disc would allow the pressing of vinyl copies. These discs also play at 33.3 revolutions per minute (RPM), which, combined with the sixteen-inch diameter, synchronizes with reels of film.

In 1948, when Columbia developed the LP record, it reused the vinyl material and the 33.3 RPM features. With advances in disc cutting over the decades, it was able to decrease the diameter of the disc down to twelve inches owing to a smaller groove width.

So, no, the 33.3 RPM doesn’t come from 78 = 45+33. The audio world is full of myths. Some are harmless. Some are funny. That’s one of both.

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