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Explanation of how an Orthophonic horn works:

https://m.youtube.com/watch?v=WbRNkv-0W ... ljdHJvbGEg

Since when are the soundwaves "compressed" and reflected backwards to the Horn's mouth???

What's missing in the model is the bifurcated, tapered conduit running through the heart chamber to the horn's mouth--separating into two sections in both the upper and lower parts of the heart chamber before reuniting at the horn's mouth. This enables a constant "forward flow" of the sound waves from the small to large end.

Also, the horn is six, not nine feet long in the Credenza model.

Wrong, for certain...

Indeed, there are two "bifurcations" or divisions in the sound pathway; the first, laterally (split left and right) then a 180 degree turn in each direction, and the second, vertically, with half of the sound directed above the mid-line and half below the mid-line of the "mouth" of the horn. (See diagram) The YouTube presenter's claim of "compression" makes no sense from a physics point of view.

HMVDevotee wrote: Thu Apr 17, 2025 5:32 pm Wrong, for certain...

Indeed, there are two "bifurcations" or divisions in the sound pathway; the first, laterally (split left and right) then a 180 degree turn in each direction, and the second, vertically, with half of the sound directed above the mid-line and half below the mid-line of the "mouth" of the horn. (See diagram) The YouTube presenter's claim of "compression" makes no sense from a physics point of view.

Many thanks for posting the image. I was editing my post while you were submitting.

I think the plastic model, supplied by Paul Eddie, was for the amplification of iPads, and was for sale a number of years ago.

Here's a post showcasing a model of an Orthophonic horn offered by the Victor Talking Machine Company.

viewtopic.php?t=58245

Yes, an example of an enthusiast’s explanation of a scientific concept. I suspect the engineers at WE did many calculations prior to their experiments. I doubt it was solely developed by trial and error as presented in the video.

The horn model available for an old iPhone version as seen in the video was a joint effort between Bob Baumbach and Paul Edie. The clear plastic one was the best as you could see the sound path. It was apparently modeled after the mahogany Orthophonic demonstration model found in the dealer showrooms

Here is a link to the booklet published by Victor to explain the Orthophonic principle.

http://www.mulhollandpress.com/styled-2 ... index.html

Mark

MarkELynch wrote: Fri Apr 18, 2025 8:52 am Yes, an example of an enthusiast’s explanation of a scientific concept. I suspect the engineers at WE did many calculations prior to their experiments. I doubt it was solely developed by trial and error as presented in the video.
The horn model available for an old iPhone version as seen in the video was a joint effort between Bob Baumbach and Paul Edie. The clear plastic one was the best as you could see the sound path. It was apparently modeled after the mahogany Orthophonic demonstration model found in the dealer showrooms
Here is a link to the booklet published by Victor to explain the Orthophonic principle.
http://www.mulhollandpress.com/styled-2 ... index.html

Mark

Hi Mark:

Many thanks. In fact, here's a diagram, culled from the original Orthophonic horn patent--which I've included--showing the sound path inside the "heart" of the exponential horn. Someone who is a YouTube member (I'm not) may want to pass this along to the "Dyslexic Genius."
FROM:

It’s a re-entrant (‘folded’), exponential horn.

Yes, a re-entrant type horn as stated in the patent. The sound path is folded or doubles back on itself.

Ortho, thanks for posting the link to the Harrison horn patent. Victor paid large royalties for the use of this design, see the Victor notes at the Hagley Museum, these are available on line and describe much of the inner workings at Victor from a high level.

Notice that the horn doors were included in the patented design and were suggested to be an extension of the horn length.

Mark