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Post by menophanes on Mar 23, 2017 6:38:12 GMT -5
I often wonder how different the history of sound recording would have been if only Edison and the other fathers of the cylinder machine had recognised the importance of a flywheel – something corresponding to the turntable of a gramophone – in smoothing out irregularities in the speed of the motor. The principle was known, since flywheels are found on some of the very early tinfoil machines; the problem was known, since from about 1900 onwards the record companies pushed the rotational speed higher and higher in an attempt to deal with fluctuations of pitch; why on earth did nobody put these things together and draw what seems to me the obvious conclusion? Edison's 'Opera' model had a small flywheel, as did a few of the early Amberolas, but after 1914 this feature disappeared.
Imagine a phonograph with a flywheel seven or eight inches in diameter mounted horizontally under the motor and driven by a bevel or worm gear, so that it only adds an inch or so to the height of the case but does not otherwise add to its bulk. Most probably this would have allowed the revolution speed to be reduced to 80, so that a 100tpi cylinder would play as long as a 12-inch disc while an Amberol, playing for nearly nine minutes, could accommodate a classical overture or short symphonic movement without a break. At the same time the cylinder's advantage over the disc in lack of surface noise would have been enhanced, and the motor would have been quieter as well. Could this have been enough to tilt the balance of public favour back towards the cylinder and encourage further development of the latter? Might we eventually have had stereophonic Amberols playing for an hour at 20 r.p.m.? Who can say?
Oliver Mundy.
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Post by lucius1958 on Mar 24, 2017 4:21:09 GMT -5
Well, the Edison studio recording machines did have flywheels.
BillS
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Post by menophanes on Mar 31, 2017 7:33:26 GMT -5
Thank you, BillS!
Perhaps rather foolishly, I have never considered that the recording machines used by Edison and other cylinder-makers might be different from the production models; after all, the latter were usually designed to be capable of recording, and the opera-recording pioneers Lionel Mapleson and Gianni Bettini both used ordinary machines (Mapleson had a Model A Home) modified only by the fitting of Bettini's special recorder and reproducer.
Are there any pictures available of professional cylinder recording devices?
Oliver Mundy.
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Post by lucius1958 on Apr 1, 2017 2:56:25 GMT -5
You can either look into the Edison National Historic Site, which has a few originals, or check Shawn Borri's site (or his posts on the Talking Machine Forum: he uses the name edisonphonoworks): he has put together a recording machine of his own, with an original Edison studio recorder.
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Post by edisonphonoworks on Apr 28, 2017 18:09:53 GMT -5
The machine with the white cylinder is one of the actual phonographs that recorded Edison commercial masters. As you can see it has a flywheel. The Edison company had several mastering phonographs, also masters are recorded at 97 1/3 tpi for two minute and 194.66666 for four minute, this is for the shrinkage rates of the master, mother, working mold, and material shrinkage. The feed screw was mounted on the back of the upper casting, and has a 16 tooth gear in the back, chain driven from an 8 toothed gear for four minute or 16 toothed gear for two minute located on the mandrel shaft, which does not have a feed screw on (the original machine located on the bottom) . It is an Edison Triumph model A base, and 3 spring motor. The top works originally were modified Class M top works, the center keeper bearing removed, and the tab by the pulley that keep it in place removed, so that the mandrel could be removed with the master to shave the master on the mandrel the master is to be recorded on. The recording head is a trailing kind of recorder, not a carrier eye kind as found on a phonograph for public use, the studio recorder,it was mounted on an adjustable trunnion, similar to a Graphophone . Also for playback the Amberola 1-B, and 1-A, Amberola IV, Amberola V, Opera all have flywheels (two of them, on the opera and large Amberola.) The other machine is my recorder, and uses an original 1910 era Edison studio recording head. I also have the original cylinder master recording feedscrew of 97 1/3 tpi. However because of collector ignorance and all played hot potato with it "I don't know what this odd ball thing is for, you have it, no you have it???!!!) it was damaged, so I have to use it as a guide to make a new one, and to make a few pitch sizes of 97 1/3, 98,99 to compensate differences in shrinkage, and to make new gears of 8 and 16 teeth for the mandrel. I do not yet have a microscope, but am pretty good at setting the advance ball depth by the sound of the cut. The other picture is my studio recorder, this recorded commercial Edison masters, and the round ball by the cutting stylus is the advance ball, and on the advance ball adjustment arm, which is changed with a micrometer adjustment screw located on top of the recorder. The diaphragm is glass and different instruments recorded with different size from .005" to .0085" The arrangement for the cutting stylus works well, however the original one might have (none have them left) a reed of glass, and a dome in the center with rivet, and a brass or aluminum cone to a stylus holder. I have not got that far yet, this arrangement works great, records sibilants and shimmer, and deep bass. The dampening is burnt rubber layered on a regular rubber gasket. Attachments:
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