The Immortal Voice (1923) Film showing how records are made

[Lucius1958]

They mentioned playback of the recorded wax. If that was a real thing, it was destructive playback, and was used to check levels and balance before a final take was recorded. Playing back a wax master destroys it. Also the images of the cutter with the wax string coiling up on the wax blank. In reality, there would be an operator brushing these cuttings away, so they wouldn't possibly bunch up under the cutter stylus.

I agree on the 'playback' scene. Unless they used an extremely light reproducer, with a soft fiber needle, and listened to it through ear tubes, it would certainly damage the recording. That is probably why studios recorded several takes of each recording: a test pressing from the first master would be far more helpful in determining sound quality.

As for the swarf, I noticed that it appears to be blown away at one point. I know that Edison, at least, was using a suction tube to remove the swarf: did Columbia use a blower instead?

Bill

[startgroove]

Interesting that the recording process evolved into using a cutting tool instead of etching so early (1901). Yet, the technical details aren't clear. How did the engineers concentrate enough sound energy to cut through the wax? How was the volume of the performers matched? (In the video, a small horn is near the singer who had a reputation for having a powerful voice, while the orchestra is some distance away.) In addition, what means was used to keep the weighty recording "head" from sinking into the wax, or how did they keep the groove depth uniform? Was there a standard amongst all record manufacturers for the record dimensions, such as spacing between grooves, groove depth, groove wall angle and cutting angle, for example?

[Wolfe]

Here's the Roberto Alagna acoustic recording session from 1997.

Some of the questions in the above post might be addressed in the video : https://www.youtube.com/watch?v=PcfZlub3meg

Like, you can see the counterweight on the recording head.

There wasn't really a "standard" groove until the 33 ⅓ rpm LP record came in. And even that changed slightly when stereophonic LP's were introduced. That's why finicky 78 collectors who play records on modern turntables collect a number of different styli to play their records. http://www.vjm.biz/styli.htm

[Henry]

Many thanks for that link to the stylus info! It has a lot of essential information.

Years ago, I purchased a Stanton 681EEE cartridge, which I still own and use for 33-⅓ LPs. I believe I also have a 500 lying around here somewhere. Kinda scary to read the prices on these discontinued items today!

[edisonphonoworks]

Master waxes. Solid wax discs were used for masters for most disc companies after 1901. The first Victor solid wax disc made by E.R. Johnson, for early Victor recordings was of melted Edison brown wax cylinders. Vocalion and Edison both used saponified stearic acid, with Montan wax compound, The metal was red or white lead oxide (PbO) added which is a yellowish or white powder when the saponification solution was added (See reproduction of sound by Henry Seymour for other formulas for disc record masters.) PbO reacts With strong base, PbO dissolves to form plumbite(II) salts:[6] PbO + H2O + OH- → [Pb(OH)3]- In Germany a special preparation of paraffin, and ozokerite were used for disc masters. Beeswax in, of itself was not used for a disc master. A mixture of petrolized ether and Beeswax was used to coat Berliner zinc masters, after being filtered into a bottle, the solution poured on both sides of a zinc disc that was highly polished. After being recorded ,where the stylus had exposed the zinc, by the action of the diaphragm and stylus, the master was etched with a water and Chromic acid solution. The zinc washed, and the wax removed from it, and it was then electroplated as the master for Berliner discs. The later wax disc process, after the recording the master disc, was either coated with fine,purified graphite (It was treated with alkali in water, and dried to remove inpurities.) this made the master conductive to electricity. Also silver and gold Vaporization was used, similar to that of making cylinders. This coating on the master made the wax conduct electricity, and then put in a copper sulfate bath that grew a master on the wax master. How to keep the recording head from sinking in the blank? If you notice two knobs by the recording head, the head is fixed and rigid, the two adjustment knobs adjust the head into the master disc. some used a sliding connection like the rigid arm victors and the head given some pivot, those use an advance ball to keep the head sinking in. Remember the debate about the so called vertical head, the aluminum one, with the red dampening, and advance ball, but the weird cantilever, that is a British lateral recorder, and is demonstrated in the Henry Seymour book. Disc masters are supposed to have a constant string of wax, and not a powdery shaving. The wax master moves under a fixed recording head., the master disc is made to have no wobble, very smooth, and the turn table heavy. Notice the test grooves before the main grooves, these are to get the depth of cut correct. The turn table is weight driven and also is on a sled, the wax disc moves also on the feed screw under the fixed recording head.

[Marco Gilardetti]

I wonder if Rosa Ponselle was facing away from the horn for the benefit of the film.

Yes, I think so. All the essays that I've read on acoustic recording techniques (like Daniel Marty's The Illustrated History of Phonographs, or Talking Wax by Leroy Hughbanks) agree on the fact that acoustically recording a voice with orchestra was an extremely difficult task, not to be taken lightly as it is seen in the movie.

Her voice pinning the meters is one of those nonsense folklore things about singers, as it simply depends on the level of amplification given to the microphone signal. Basically everybody could top a meter.

It's interesting to note that some Ponselle's fans have commented that, until now, it was unknown that she ever acted in a movie about recording: none of her biographies mention it.

[Wolfe]

Her voice pinning the meters is one of those nonsense folklore things about singers, as it simply depends on the level of amplification given to the microphone signal. Basically everybody could top a meter.

I'm not sure it's all nonsense folklore. Certain singers (I think Flagstad was another) acquired reputations for giving engineers fits at times. But one would like to have to have experience working with the very basic microphone setups, compression gear, cutterheads, mixers, etc of 70 or 80 or even nearly 90 years ago. And with that gear, achieving a satisfactory, balanced monaural recording onto wax with an orchestra backdrop and a singer who has a loud penetrating voice that is used to filling auditoriums.

They dealt with that in the acoustic days by having singers measure their distance from the horn depending on how loud they were singing.

I have a microphone here. If I plug it in and crank the gain enough and whisper into it, I'll top the meter. But that's not the whole enchilada.

[edisonphonoworks]

The best way to find out about professional acoustic recorders, is to find someone who owns one, and experiment, with a singer, change diaphragm thicknesses, dampening material, horn placement. I know of only a few people, who have professional recorders, Peter Dilg, Myself, Duncan Miller, and Michael Devecka. If you are serious to learn the answers to these questions, you need to experiment with the real equipment or build copies of it. I have invited the collector community to experiment and nobody has taken this offer up. If you have a question about this, you certainly can experiment and see what happens. Glass diaphragms are much more sensitive than you would imagine, I use a .0075 and .008 mostly, they are sensitive, and have clear high frequency response. Thinner glass is used for bass and baritone singers, and instruments like clarinet and violin, softer instruments. Also the kind of horn you use, its opening and shape, the dampening ect. Any Takers? What I have found out is that a professional recorder is very sensitive indeed, in fact you can whisper softly, even with a .008 glass and it will record it. I don't have the loudest voice in the world, and I made very loud recordings with the recorder about 4" from the horn, and it will be over modulated if I get into the horn, it records sibilants very clearly. And this is with a very leaky trunnion, not up to standards yet. I plan soon to machine a more proper one with solid barrel, and leak proof between the barrel and outer tube, this will increase the sensitivity even more! It is very hard to describe the difference between a home recorder and a studio recorder,but the sensitivity is much much greater with an advance ball, trailing recorder.

[Curt A]

The thing about the video that interests me is the fact that it predicts the record life as 100+ years, when no one really knew. We are now the "children of the children" 100 years later that are still enjoying the original records...