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I am curious about the development of the sound box as exemplified by the Victor No. 2 and Exhibition sound boxes. I wonder if any member of the listserv is aware of documentation of research, notes, etc., on this subject? Searching for patents in Google Scholar is pretty daunting, as is a search of the patent gazette. I read the pages in Victor Data Book about sound boxes, and there are some references there to documentation the author found in preparing the book. I wonder if there was any effort to record experiments with these at Victor? Was it hit-and-miss? I assume that by the time of the orthophonic soundbox, there would have been quite scientific approaches to establishing the size of the diaphragm, configuration of the spider, etc., etc., but that is the kind of thing I am curious about with reference to the earlier versions. Anybody know of a handy dissertation on sound box development?
Thanks in advance. I am always grateful for the considerable help of members.

This is just my opinion and not based on any scholarly research. But before the introduction of the Victor #5 orthophonic reproducer, I don't believe that there was any real science applied to reproducer design. It was cut-and-try, and buy-guess-and-by-golly. "Gee Ralph, that little twiddle that I did to the needle bar sounds better, don't ya think? We'll apply for a patent with some jibberish claims that really don't mean anything and then let's put into production". You see all kinds of little tweaks and twiddles done to the basic design of the reproducer from the very first Victors all the way up to the #5, and in all the competitors' designs. And they all turn out to be pretty much the same basic design when you ignore the details that don't really contribute much to the sound of the units.

But the Victor #5 was actually designed from an analysis of the need to match the exponential horn that these were used with. Western Electric made a big deal about the "matched impedance" blah blah of this design, but most of that was pretty much hot air so far as the reproducer goes. The soundbox design is STILL not much different in principle from all the earlier ones. However, they did manage to address some significant issues such as the use of a more compliant diaphragm as realized in the use of the corrugations in the aluminum and the need for reducing the moving mass of the vibratory elements. Beyond that, the "matched impedance" jargon was mostly sizzle used to sell the newfangled steak. The biggest improvement in the Victor ortho phonos was the use of the expenential horn which WAS in fact a result of proper mathematical analysis applied to the problem of designing an mechanical impedance transformer that is required to couple the high-pressure output of the reproducer to the low pressure emission from the mouth of the horn. That's what the horn is - a mechanical impedance transformer, not an amplifier as it was commonly referred to in early advertising.

I think Greg's right about the "by guess and by golly" approach Victor took to sound boxes before the Ortho. There's a section in Antique Phonograph Accessories & Contraptions showing a number of experimental Victor sound boxes. Looking at some of them, it's difficult to imagine that anyone could have thought they would work! Some really crazy designs clearly based more on imagination than physics.

George P.

Thanks for the comments. I will look for that book. There is a section in Victor Data Book about experimental horns and early attempts to amplify using phone components. I have the idea that Victor was very careful about maintaining its control over components. It would be good to look at patents, I think, but I was hoping for notes. I read that the No. 2 sound box was approved by a committee before being put into production. The guess-and-by-gosh method can only have worked so far...

johnwilla wrote:Thanks for the comments. I will look for that book.

Maybe this will help:

http://forum.talkingmachine.info/viewto ... ire#p91754

George P.

gregbogantz wrote:The biggest improvement in the Victor ortho phonos was the use of the expenential horn which WAS in fact a result of proper mathematical analysis applied to the problem of designing an mechanical impedance transformer that is required to couple the high-pressure output of the reproducer to the low pressure emission from the mouth of the horn. That's what the horn is - a mechanical impedance transformer, not an amplifier as it was commonly referred to in early advertising.

Very interesting Greg, thank you.

"...a mechanical impedance transformer..." Perfect.

Best,
Fran

johnwilla wrote:Thanks for the comments. I will look for that book. There is a section in Victor Data Book about experimental horns and early attempts to amplify using phone components. I have the idea that Victor was very careful about maintaining its control over components. It would be good to look at patents, I think, but I was hoping for notes. I read that the No. 2 sound box was approved by a committee before being put into production. The guess-and-by-gosh method can only have worked so far...

"Guess and by-Gosh" + Committee = ( ? )


I'm sure there were lots of notes... goodness knows what became of them though, especially after E.R. Johnson sold the company.

Just from my own hands-on / ears-on observances, as far as what made it into production, until the Orthophonic sound box, the Victor "Exhibition" box was probably Victor's greatest technological improvement in the field.

The Victor # 2 is basically a larger version, with a redesigned case-back, to eliminate that large rubber back-flange, and the Victor # 4 was bigger yet.

Kind of like the prevailing philosophy with most automobile engine designers of the same era, "bigger = better".


Just my morning musings on the subject, before my 2nd cuppa...

You might find this article interesting concerning acoustic properties of different Victor soundboxes:
http://victor-victrola.com/Soundbox%20Article.htm
Bob

The Orthophonic soundbox with the corrugated aluminum diaphragm was designed by Western Electric engineers, not Victor.

De Soto Frank wrote:Just from my own hands-on / ears-on observances, as far as what made it into production, until the Orthophonic sound box, the Victor "Exhibition" box was probably Victor's greatest technological improvement in the field.

From my extremely limited experience, based on a comparison of my Exhibition with a single example of a no. 2 sound box, I have to concur with Frank on this. And Paul Edie's results seem to support our similar subjective experiences.

My Harry James recordings on Columbia red-label microphone bear this out, and how! And my Caruso acoustic "Celeste Aîda" blows me out of the room on the high notes.