The Talking Machine Forum — For All Antique Phonographs & Recordings

http://www.youtube.com/embed/G0Hb28ePqpo

In this video you will see how to properly record with a Standard speaker style recorder, with a glass diaphragm and brass horn. You will note how quiet a new Borri Audio Laboratory blank is, and the clear, natural recording quality, all components are historically accurate to a recording session of the mid 1890s, except the 160 rpm speed used in this video. Pleas watch before you comment.

A great demonstration, and an amusing Cal Stewart imitation!

Thank You !

I couldn't get your supplied link to work
Thanks, now I can!

It's interesting that you did a demo with a glass diaphragm recorder. However it would be more revealing of the quality possible with cylinder recording to recreate a late cylinder recording with a viscous damped recorder with a ball follower that controls recording depth, and on a machine with a flywheel, such as was used in the recording studios to minimize flutter. Do these items exist?

I couldn't get the link to work, either. Any chance you can post a link where you can just click on it? I'd love to see it.
Harvey Kravitz

I would love to build one of the late model recorders, I want to work on one this summer. Peter Dilg has a recorder like this, he says that for all normal purposes he likes one particular home recorder,with a glass diaphragm better. Does anyone know what that material was, it is said to be like burnt rubber for the dampening. I might try sorbothane for dampening material, Some diaphragms were supposedly dome shaped of cellulose material. The existing recorders at Edison are missing the stylus and linking pin. Some used wire or string tensioned to hold the cutting stylus center, and then there is the advance ball for adjusting the depth of cut.

It has been said that Edison (and the other firms) didn't apply for patents on all their improvements, so as to keep them secret from the competition. Viscous materials (such as Edison used at last for the damping on his recorders) are semi-liquids, much much softer than any rubber or synthetic rubber materials. The closest thing that comes to mind is the material called composition that was used for printing ink rollers for letterpress, now only one company makes. It is basically a mixture of molasses and glue, plus some other ingredients. I'm sure you could make it easily, and you can google a recipe. Just google for Composition printing rollers. I am assuming the damping would be the material that forms the gasket on the outside edge of the recording diaphragm.

With an advance ball, you could load the cutter with enough weight that it would never bounce on loud tones, thus creating a more accurate cut, yet not cut too deep.

Ever see that stuff they use to stick plastic
cards to letters you get in the mail?

It's kind of sticky, and it's a lot like
rubber cement. Something of that general
consistency and elasticity would (I think) be
a good candidate to try for doing "viscous damped" recorder diaphragm experiments.

Another idea is to cast some very soft recorder
gaskets using silcone RTV from the hardware store. A simple mold could be made from some
rather thick aluminum plates bolted together.

Gaskets could be cast in whatever thickness that one would want to try.
I would start out at maybe .015 to .020 inch thick.

The plates could very easily be machined
using a milling machine with a fly cutter.

One plate would be flat, the other would have
the milled ring for the RTV. The milled ring
could be filled with RTV then scraped off,
then the flat plate bolted on and the whole
works set aside for a few days.

I imagine that possibly rubber cement could be
cast into recorder gaskets the same way.

Shawn, as far as manipulating one of those
ancient recorders to work well, and speaking
from my own experiences so far of taking apart
my Automatic Recorder and adjusting it:

To put it like Uncle Josh would say:

"The language I used was just shameful!"

Chuck