Did Edison license blue amberol technology to Columbia?

[PeterF]

I recently obtained a Dictaphone Practice Record. It's a cylinder, shaped like normal Ediphone and Dictaphone cylinders, same diameter as entertainment cylinders but with a thicker wall and longer.

It's pre-recorded, and consists of a stentorian dude elocuting dictated letters for some hapless typist to transcribe. I like this kind of stuff because the content often reflects the times in unintentionally interesting ways.

The thread pitch on business phonographs is different than that of the entertainment cylinders, but I am lucky enough to own a cool old spring wound Edison Business Phonograph, so that part is handled.

But here's the weirdness. The dictaphone practice cylinder is not wax, and although it does play without skipping, it is very quiet, and has bleedthrough under the main content, seemingly from adjacent grooves. Closer examination reveals that the cylinder seems highly similar in composition to the Edison Blue Amberol, except black in color. I'm not with it now so can't say whether there is a plaster core, but I don't think there is.

My Business Phonograph is early and its reproducer is as well. Perhaps later on, all Ediphone and Dictaphone systems went to a tighter or thinner groove and so my stylus is just too fat. I thought to put a Model H reproducer on it to test that theory, but it isn't compatible to the carriage configuration.

I have some newer ediphones out in the garage someplace and will be able to borrow a newer reproducer to test that theory eventually. But in the meantime, does anyone know the answers to these two questions:

1. did business cylinder grooves and stylii get narrower at some point?

2. how was Columbia able create an amberol-like cylinder?

[Phototone]

Grooves stayed the same for all the years of Dictaphone/Ediphone machines. However, celluloid cylinders shrink a bit with age. That is probably the cause of your issues, or a dull stylus on your player.

Columbia took over, or signed a contract with one of the 2 independent celluloid cylinder record companies, and sold celluloid cylinders (same outer composition as blue amberols except for color)under the Columbia name, therefore they could release training records using that technology.

You DO KNOW that there were several companies that made celluloid cylinders in 2 min. and 4 min. versions (same composition as Blue Amberols except for color) except they didn't have a plaster core like Edison. Edison was prohibited from making them for several years due to patents by others.

In fact, contrary to your title header, it was Edison who had to license the technology (or buy a patent) to be able to use celluloid for cylinder recrods.

[victorIIvictor]

Columbia may not have even had anything to do with the manufacture of your cylinder, since it spun off the Dictaphone division of its business circa 1921.

Here's an example of a post-Columbia-ownership Dictaphone Business Practice Course cylinder pressed in blue celluloid.

http://forum.talkingmachine.info/viewto ... ne#p127607

Best wishes, Mark

[PeterF]

Ah! There it is - this is exactly what I have, including the black Dictaphone sleeve, but my cylinder is the deep blackish/bluish color we have also seen on some entertainment cylinders.

Now all that's missing is why it doesn't play cleanly on the Business phono from 20 years prior - either stylus wear or size mismatch. I'll briefly sample it on an entertainment machine for tone quality on an H reproducer and report back.

[victorIIvictor]

Peter,

This may be germane to what you wrote, to wit, "My Business Phonograph is early and its reproducer is as well. Perhaps later on, all Ediphone and Dictaphone systems went to a tighter or thinner groove and so my stylus is just too fat.…did business cylinder grooves and stylii get narrower at some point?"

In 2010, someone on 78 L asked if one could use a Dictaphone to play entertainment cylinders. Michael Biel responded, "The problem with regular Ediphones and Dictaphones is that […] their feedscrew thread pitches are about halfway between 2 and 4 minute entertainment cylinder thread pitch of 100 and 200 [threads per inch] respectively. The Ediphones and Dictaphones use, I believe, 150 and 160 [threads per inch], but I don't remember which is which."

What is the feedscrew thread pitch on your early Business Phonograph?

Best wishes, Mark

[PeterF]

No, that's not the issue. The carriage's rate of travel across the face of the cylinder is correct for the cylinder's threads - no skipping or repeats. Thus my query about stylii, since a wider stylus would ride high on a narrow groove and perhaps pick up mild cross-talk from adjacent grooves, which is sure how it sounds.

[victorIIvictor]

Yes, you did say that, my apologies. I guess it's hard for me to conceptualize a cylinder with "a tighter or thinner groove" than standard not having more threads per inch than standard. My quoted source also suggests that there is a difference between an Ediphone's and a Dictaphone's thread pitch. Finally, the fact that you are getting bleed-through from the neighboring grooves makes me think of the problem that happens with lateral recordings with grooves that are closer together, and the groove walls are thinner, than standard (like a K tel or Ronco LP). I'm trying to conceptualize such bleedthrough on vertical recordings as with cylinders. Curious.

But if there's no skipping, and low volume, that does seem to implicate the stylus size.

Best wishes, Mark