And it just so happened that the speed stuck around long after Vitaphone faded away as a sound for film process. sound quality all combined made 33.33RPM the speed for that purpose. In Vitaphone, the projector motor also drove the turntable, so each had to be locked to a clearly defined speed and each 16 inch disk had to have a playing time as long as one reel of film (10 to 12 mins) and still sound good. And mathematically, 78.26RPM was chosen, again as I have read, because it had to do with motor speed vs pulleys etc.ģ3 1/3RPM is similar: it has to do with it's original use as the sound disk in the Vitaphone film sound system. (I believe in the mist of my memories I remember reading most electric motors back then ran at 1500 to 1800 RPM as a rule.) So you had to use things like pulleys, idlers, or linkages like you see in old watches and record changers to achieve target speed. And again, it had to do with raw motor speed and what the various ways speed could be "stepped down." If you notice, many turntables today say things like "Powered by a 24 volt 300RPM motor." Same thing then. That's why all those old acoustic phonographs have fairly wide speed controls - motors weren't all that accurate back then.)ħ8.26 came after electric motors became the norm. (Those early acoustic discs can be anywhere from 70 to 90 RPM. After all that, around 78RPM was that median. So supposedly it was a balance between availability at the time of a smooth enough high-speed spring wound motor that had low cogging and acceptable speed stability combined the kind of common step down pulleys available to come up with a median speed that would give a reasonable playing time per disc vs. The earliest Berliner gramophones actually were closer to 80RPM on average than 78.26.īerliner had some set goals: he wanted a flat disc that sounded at least on par with Edison's cylinder, and with the disc size he was proposing (5 to 7 inches) it had to play at least as long as a typical Edison cylinder of the period. It bears remembering, the 78.26 speed came about over a period of time and wasn't "locked in" until well into the shellac disc's lifetime. (Forum speak for "I can't name or remember the actual sources, so take this at face value and don't quote me but this is the gist.") None of it was happenstance, and almost all of it had a solid engineering and mathematical basis.Īs I recall it. And all were connected to the various technologies of the time. Over the years I've heard more scientific explanations for the choice of speeds records play at. Lots of bad, oversimplified and just plain wrong info there. Presumably, it is powered by the spinning 33 RPM platter, and gears this down to 16 RPM for the record placed on top.Click to expand.That's a pretty poorly researched and written webpage. While the mechanical details are not explained, it allows a 16 RPM record to be played on a 33 RPM turntable. The article does include an interesting adapter, shown here. Eventually, curiosity got the better of me, and I checked out a 16 RPM talking book from the library, just so that I could play it at home. If you search eBay today for 16 RPM records, the most common search result is this talking Bible.Īs a kid, my record player had the setting for 16 RPM. The format was used mostly for “talking books.” The best seller was probably the Bible, which was recorded in the early 1950’s at the lower speed. At the time, the maximum frequency response went only to about 9000 Hz. But the article noted that the speed, while longer playing, had inherently lower fidelity than higher speeds. Most notably, some records were produced for the benefit of Chrysler’s Hiway Hi-Fi experiment, which included a record player for the car. The 1957 article predicted, erroneously it turns out, that “the growing catalog of recorded material and new playback equipment in all price ranges proclaim that the tide may yet turn to 16 rpm and roll into the arena with quite a splash.”Ī few musical recordings were issued on 16 RPM. More precisely, the records played at 16-2/3 revolutions per minute, and most moderately priced phonographs in the 1960’s would play the speed, along with the more common 33, 45, and 78 RPM speeds. Sixty years ago, the August 1957 issue of Popular Electronics carried an article about the forgotten stepchild of audio recording: The 16 RPM record.
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