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Questions about Constant-velocity records....
Posted: Thu Sep 09, 2010 7:46 pm
by transformingArt
I have heard a number of times about the constant-velocity records, and I recently got a copy of a Korean record which was recorded with that system, but so far never had a chance to see the actual one, nor anyone who has a enough knowledge about them.
There are couple of questions I have to ask to any of you,
1. How many record companies have made that kind of recordings? I have seen a video on YouTube which the British collector Norman Field shows one of his 'World Record', and I have a CD from Japan which contains half of dozen those 'Constant-velocity' recordings made and sold by Nitto Company in Osaka between 1924 and 1926. But I wonder big major companies like Victor, HMV or Columbia have dabbled with these.
2. How did they play this record on the acoustic phonograph? Certainly those machines couldn't be slow down to 33rpm or less, although I have experimented with Victor table-top models with speed screw to play 45rpms (EPs).
3. Is it possible to play them properly on Modern equipment?
Re: Questions about Constant-velocity records....
Posted: Thu Sep 09, 2010 11:07 pm
by Phototone
Normally, the constant velocity records were intended for play on dedicated purpose-built players..not intended for general use. Kinda a captive audience, like the Busy Bee and Aretino records and machines, but of course those weren't constant velocity. All Cylinders are constant velocity, by the way.
Re: Questions about Constant-velocity records....
Posted: Fri Sep 10, 2010 2:34 am
by gramophoneshane
transformingArt wrote:
2. How did they play this record on the acoustic phonograph?
I dont know about other brands, but world records are played on any gramophone using a world record speed controller.
Re: Questions about Constant-velocity records....
Posted: Fri Sep 10, 2010 3:50 am
by gregbogantz
Yes, the World Record Controller was used to convert conventional turntables to operate at the variable speed required to play the constant linear velocity (CLV) records. This adapter could be used on any turntable motor that was capable of being set to the highest speed required at the inside diameter of the CLV record and was compatible with being slowed down by mechanically braking the platter. In other words, it worked with just about any spring motor made during the acoustic era as well as with a number of the newer electric motors that employed a flyball governor. The CLV controller was a device that had a rubber-tired wheel that rode on the surface of the record and which had sufficient grip of the record such that it could brake the turntable. This wheel drove a flyball governor that was built into the CLV controller which kept the wheel turning at a set maximum speed as determined by a speed control on the CLV controller, similar to that of a conventional spring motor. The wheel carriage traveled on a feedscrew system that allowed it to traverse the radius of the record from the outer diameter to the inner. This feedscrew was driven by a friction wheel that was driven by the outer diameter of the turntable platter. Since the rubber wheel was constrained to turn at the set maximum speed as set on the controller dial, as the wheel traversed from the outer to the inner diameter of the record, the record spun faster as the wheel moved to the smaller record diameter. This caused the groove to pass under the wheel at the same velocity regardless of its location on the record radius. This created the CLV operation. The reproducer or pickup was placed on the record at the same radius as the CLV controller wheel and the stylus would see the groove pass under it at constant linear velocity. Note that as the CLV wheel got to smaller diameters, the platter speeded up which caused the CLV controller feedscrew to also turn faster which advanced the wheel faster to even smaller diameters. See the attached photos.
Re: Questions about Constant-velocity records....
Posted: Fri Sep 10, 2010 6:46 am
by Starkton
Below is the patent drawing of a device to record and reproduce constant linear velocity records. It was patented by Louis Rosenthal and Salomon Frank, both of Frankfurt/Main in November 1891, and built in a small series!

Re: Questions about Constant-velocity records....
Posted: Fri Sep 10, 2010 1:34 pm
by Lenoirstreetguy
I have read that they were slow to catch on because the controller was fussy to use. Once the rubber began to harden slightly the speed control became unsteady. World would have done better to have convinced one of the machine manufacturers to incorporate their mechanism.
Jim
Re: Questions about Constant-velocity records....
Posted: Fri Sep 10, 2010 1:47 pm
by estott
I've also read that the tone of World Records was unsatisfactory.