This is the new data sheet for Truextent beryllium foil.
http://www.s-m-audio.com/truextent.pdf
I have received several thank you notes from friends and colleagues for my efforts to clean up the loudspeaker industry but none nicer than a short message that I received from Roy Allison.
Steve,
This is an important story and must be the result of many, many hours of work. Where will it be published? Or has it been published and I missed it?
Congratulations on a brilliant bit of investigative reporting.
Regards,
Roy
You can read my interview of an all around nice guy here.
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/mowry509.pdf
http://www.s-m-audio.com/truextent.pdf
I have received several thank you notes from friends and colleagues for my efforts to clean up the loudspeaker industry but none nicer than a short message that I received from Roy Allison.
Steve,
This is an important story and must be the result of many, many hours of work. Where will it be published? Or has it been published and I missed it?
Congratulations on a brilliant bit of investigative reporting.
Regards,
Roy
You can read my interview of an all around nice guy here.
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/mowry509.pdf
Steve
Nice piece.
I completely concure on the power response versus axial response. I completely disagree that the dispersion should be as wide as possible. I have never understood where this idea came from that the sound from the speakers should go everywhere. Anyways, I do seem to be alone in the view that narrow directivity is useful. Even Floyd Toole would concur with Mr. Allison. Only time will tell.
Nice piece.
I completely concure on the power response versus axial response. I completely disagree that the dispersion should be as wide as possible. I have never understood where this idea came from that the sound from the speakers should go everywhere. Anyways, I do seem to be alone in the view that narrow directivity is useful. Even Floyd Toole would concur with Mr. Allison. Only time will tell.
Max dispersion is about artificially enhancing ASW. It's a counterproductive approach in many respects, as it turns over control of everything to the room. Soundstage and imaging become mutually exclusive.
Cue extraction can accomplish the same with minimal impact on the rest, and Earl teaches one productive method -- minimize the early ipsilateral first reflection and emphasize the later > 10 ms. contralateral one.
Allison has narrowed his time window to 30 ms.
Progress.... 😀
Cue extraction can accomplish the same with minimal impact on the rest, and Earl teaches one productive method -- minimize the early ipsilateral first reflection and emphasize the later > 10 ms. contralateral one.
Allison has narrowed his time window to 30 ms.
Progress.... 😀
There have been people that have come forward and provided more information regarding this topic. I will outline some new information below.
The Usher Beryllium is not an alloy. It is a powder coated like titanium foil. The beryllium and thus the beryllium color is either painted on or vapor deposited. A typical metal tweeter dome is about 30 microns thick. The content by mass of the Usher dome is 0.6075% beryllium. Because the density of the beryllium is low relative to the titanium, the percent by volume is about 1.5%. That is consistant with an coating of about 0.3 micron on both sides of the titanium. I have simulated this and the effect of the beryllium coating is pretty much zero. I cannot find any refrence to a titanium/beryllium alloy anywhere on the Internet and if I did find a 2% nominal beryllium alloy it would not be a close match to the bluish-steel gray color of beryllium foil like the Usher domes are. As with the CuBe2, a TiBe2 would have the color of titanium. Just like CuBe2 has the color of copper. AlBeMet 140 is 40% Be and 60% aluminum and it has an aluminum color. Usher's domes are a close color match to acoustic grade beryllium foil. They have no noticable smell but something stinks here.
This is consistant with testing in 2004 of parts from Usher's supplier, SONIC with offices in Taiwan and factory in China.
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/BogusBeryllium.pdf
Would you call aluminum metalized poly bags, aluminum bags and write Aluminum right on the bag? The analogy to Bogusium is very close.
Now are all you Decepticons tuning in?
The Usher Beryllium is not an alloy. It is a powder coated like titanium foil. The beryllium and thus the beryllium color is either painted on or vapor deposited. A typical metal tweeter dome is about 30 microns thick. The content by mass of the Usher dome is 0.6075% beryllium. Because the density of the beryllium is low relative to the titanium, the percent by volume is about 1.5%. That is consistant with an coating of about 0.3 micron on both sides of the titanium. I have simulated this and the effect of the beryllium coating is pretty much zero. I cannot find any refrence to a titanium/beryllium alloy anywhere on the Internet and if I did find a 2% nominal beryllium alloy it would not be a close match to the bluish-steel gray color of beryllium foil like the Usher domes are. As with the CuBe2, a TiBe2 would have the color of titanium. Just like CuBe2 has the color of copper. AlBeMet 140 is 40% Be and 60% aluminum and it has an aluminum color. Usher's domes are a close color match to acoustic grade beryllium foil. They have no noticable smell but something stinks here.
This is consistant with testing in 2004 of parts from Usher's supplier, SONIC with offices in Taiwan and factory in China.
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/BogusBeryllium.pdf
Would you call aluminum metalized poly bags, aluminum bags and write Aluminum right on the bag? The analogy to Bogusium is very close.
Now are all you Decepticons tuning in?
Hi Earl,gedlee said:
I think the angle where you place the sound in the sound image changes.
There for the hight and with and depth might change with the dispersion.
Example:
When I got no dispersion, with a head phone on my head I place the sound stage in my brain.
And I am afraid may head will pop
😀 Regards Helmuth
I was told (by a Usher dealer who once had a tweeter dome analysed on a local university) that the material is actually BeO, not metallic Be.
Henkjan said:
BeO is white and is considered the most dangerous form of beryllium because it is so brittle.
Here's what one USA engineer said to me.
"Many years ago I used BeO insulation washers on power transistors.
BeO is very fragile, breaks easily, toxic dust.
It is not as tough as Alumina or Silicon Nitride.
BeO is the last thing I would choose for a speaker diaphragm."
JRace said:
Last year when I wrote my discussion of engineering materials for audio applications, I looked at all available materials that I could find and I came to the conclusion that Beryllium is the "best" material available and clearly stated that then.
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/mowry1208.pdf
http://www.audioxpress.com/magsdirx/voxcoil/addenda/media/mowry109.pdf
Now having said that and like it or not, the beryllium foil is only available from Brush Wellman Electrofusion. This is just a cause and affect.
What can one do?
Steve
I would have to agree that Be extremely low density and high stiffness makes it ideal as a diaphragm material, I'm just not sure that its "necessary". Thats an entirely different question. I'm not into "cost is no object" - its too easy. "Best value" is a whole lot harder engineering problem.
By the way, nice writup in VC's 2009 Loudspeaker Sourcebook. Thanks for the plug!! I agree with your assesment about the big guys turning their backs on technology. Problem is that its the whole US economy is doing this, not just Audio, although Audio is notoriuosly bad!
I would have to agree that Be extremely low density and high stiffness makes it ideal as a diaphragm material, I'm just not sure that its "necessary". Thats an entirely different question. I'm not into "cost is no object" - its too easy. "Best value" is a whole lot harder engineering problem.
By the way, nice writup in VC's 2009 Loudspeaker Sourcebook. Thanks for the plug!! I agree with your assesment about the big guys turning their backs on technology. Problem is that its the whole US economy is doing this, not just Audio, although Audio is notoriuosly bad!
mowry said:
Still not showing objective third party data on the supplier you endorse. Please, do stop the mud thowing and generate some fair data. In the past, you had endorsed SONIC, and even did so on your web site. Now the mud throwing. This all just gives a bad taste to the audio industry like a marrage gone bad. The mistress versus the ex.
soongsc said:
That was part of the trap and it worked. I was able to obtain sample Bogusium cones and the SGS test report. These folks tend to hang in the darkness and it's a challenge to get any information from them. The representative was concerned that the Taiwan Government would get invoilved. Taiwan has laws prohibitting the import and export of beryllium because of its stratigic material status (used in the trigger of nukes). The company that represent SONIC in Taiwan actually asked me to help them to understand the Bogusium. They could not even understand the report. Once the information came together this company resigned as SONIC's representative. There comment was that SONIC had mislead them. I have kept this comapny confidential to temper their damage.
Henkjan said:
I have met with a few people that have worked on these types of diaphragms. Yes, they are brittle and toxic. But the things is, people that started to look into this kind of material look for people that were willing to risk thier health and lives just for the sake of having the work to do. For those that lived in developed countries, they either wanted VERY high pay in comparison to do the dirty work, or just flat rejected the work even though they were on wellfare.mowry said:
Now these same people are being abused and bashed by some fancy talk. What justice is being done?
I am not sure what company asked you to understand such products, but after you started this whole thing a while back, we actually contacted SONIC. To me, they seem to provide very good information about thier products. However, having worked in various technical areas, I understand how difficult it is to express the proper technical spects in a second language, and even the mother language; I would hate to have to write a technical document in Chinese. Additionally, most people in the industry do not have a very good education background, and tend to use very simple words to communicate, and can lead to misunderstanding even for me. To be protective of any information detail is a standard practice any company should take, so I certainly understand there are more concerns about price competition, the same reason other foreign companies come to this area of the world, to take advantage of the price competition.mowry said:
I was in contact with a local workshop that does metal diaphragms. The owner did not even know how to operate a computer, finally, I just told him that we would prepare a mold if he would do the work. It's at that low level.
" Yes, they are brittle and toxic. But the things is, people that started to look into this kind of material look for people that were willing to risk thier health and lives just for the sake of having the work to do. For those that lived in developed countries, they either wanted VERY high pay in comparison to do the dirty work, or just flat rejected the work even though they were on wellfare."
Hello Soongsc
The real danger is during the fabrication of these materials. As long as you follow the handling procedures in the MSDS during manufacturing you will be fine. The finished products are quite safe and are a cake walk compared to many industrial materials. If you work painting cars your health is in much greater danger than handling any finished Berylium goods.
I work with BeO products every day and handle and inspect the raw BeO ceramic material as it comes into where I work. As long as you don't crush, abrade or machine it is perfectly safe. Much safer than any of the paints, epoxies, conformal coating or a host of other industrial materials that come into the factory and are used everyday.
http://www.brushwellman.com/EHS/MSDS/C10.pdf
As far as Be diaphrams being brittle the foil ones are not. They are perfectly safe to handle even after they have been damaged. The foils do not shatter like the vapor deposition ones do.
Rob🙂
Hello Soongsc
The real danger is during the fabrication of these materials. As long as you follow the handling procedures in the MSDS during manufacturing you will be fine. The finished products are quite safe and are a cake walk compared to many industrial materials. If you work painting cars your health is in much greater danger than handling any finished Berylium goods.
I work with BeO products every day and handle and inspect the raw BeO ceramic material as it comes into where I work. As long as you don't crush, abrade or machine it is perfectly safe. Much safer than any of the paints, epoxies, conformal coating or a host of other industrial materials that come into the factory and are used everyday.
http://www.brushwellman.com/EHS/MSDS/C10.pdf
As far as Be diaphrams being brittle the foil ones are not. They are perfectly safe to handle even after they have been damaged. The foils do not shatter like the vapor deposition ones do.
Rob🙂
Do you have any information on reall audio drivers showing how much better Be drivers are?Robh3606 said:
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