Confused about the sizes and speeds of different records? Let me explain.

[This was my weekly column for GlobalNews.ca. – AC]

There are some things we don’t really question: the sun coming up in the east; American politics will continue to be dysfunctional; and the Toronto Maple Leafs will once again break hearts next spring.

We can throw a given about vinyl records into that pile, too.

Have you ever wondered why they come in the diameters they do? How about the speed at which they rotate? The answers contained herein could win you a lot of bar bets.

The first format for recorded music was the Edison cylinder, a Coke can-looking thing that rotated along a horizontal axis like a piece of wood in a lathe. It was eclipsed by Emile Berliner’s rotating disc (patent 564,586) in 1888. His discs not only sounded better, but because they had two sides, double the capacity. Within a decade, the cylinder had disappeared.

But even as the idea of flat rotating discs caught on by the turn of the 20th century, there was little in the way of standards. Some companies made records seven inches in diameter. Others felt that 10 inches was better. Still others went for 12-, 14-, and even 16-inch discs. In 1904, a British company called Neophone began issuing records that stretched 21 inches across. The bigger the disc, the more music it could store. Complicating matters were the discs that played from the inside out instead of vice-versa. Of course, not all turntables could handle the peculiarities of all the records on the market.

Width was only one way to determine capacity. Another was the speed at which the disc turned. There was considerable disagreement about this at the beginning. Berliner designed his original Gramophone to play discs “at about 70 RPM.” The reason for this approximation was that this was before the age of electric motors in turntables. Spring-wound mechanisms provided the power and were notoriously inaccurate.

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