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edgewound
04-24-2007, 02:48 PM
The supplier of JBL's Be diaphragms, Brush-Wellman, did an analysis of allegedly beryllium cones and domes that were sourced from China.

What do you think they discovered?

Go to the first link in the link below, and read the report.

http://www.berylliumproducts.com/Acoustics.aspx

johnaec
04-24-2007, 02:51 PM
Similar links at: www.electrofusionproducts.com (Look under "Acoustics".)

John

Zilch
04-24-2007, 02:52 PM
The supplier of JBL's Be diaphragms, Brush-Wellman, did an analysis of allegedly beryllium cones and domes that were sourced from China.

javascript:openNewWindow('documents/China_Be_Domes_Report.pdf')

What do you think they discovered?

They are fake?

Made from Mao's melted-down cooking pots?

Earl K
04-24-2007, 06:12 PM
Thanks Edge for that tiny look-see into fake Beryllium domes .

I also appreciate the link to a bonafide US based hitech company that does make SOTA "Be" domes. Very Interesting stuff . Maybe within a decade I'll be able to afford to retrofit Be diaphragms into all my SR stuff .


:)

Zilch
04-24-2007, 09:16 PM
And those guys wore such good-lookin' suits, too.... :blink:

johnaec
04-25-2007, 08:32 AM
This posting at PwoSoundWeb quoting a JBL rep. says the JBL diaphragms are really titanium with just a beryllium coating - curiouser and curiouser... http://srforums.prosoundweb.com/index.php/m/206609/22661/0///8370/#msg_206609

John

scott fitlin
04-25-2007, 09:56 AM
Wow, so theres really no pure Be diaphragms out there, except maybe for TAD?

Whats the story on the TAD phragms, or are they also composite materials?

Zilch
04-25-2007, 10:22 AM
Engineering spec says diaphragm is 0.0016" Be foil:

http://audioheritage.org/vbulletin/showthread.php?t=14369

I just spoke to JBL Pro tech support, who inquired of engineering.

Answer: "The information is proprietary...."

boputnam
04-25-2007, 12:26 PM
The supplier of JBL's Be diaphragms, Brush-Wellman, did an analysis of allegedly beryllium cones and domes that were sourced from China.B-W mines their Be at Spor Mountain, UT (http://pubs.usgs.gov/of/1998/ofr-98-0524/HOME.HTM). Interesting place - tuffacous rocks produced from local calderas. I've been there many times, first back in 1977 during the start of my field geologist days...


Wow, so theres really no pure Be diaphragms out there, except maybe for TAD?Not exactly true...


Whats the story on the TAD phragms, or are they also composite materials?No. TAD deposits / fogs their Be onto a Cu substrate and then dissolves the Cu away leaving a pure Be diaphragm.

edgewound
04-25-2007, 12:28 PM
Engineering spec says diaphragm is 0.0016" Be foil:

http://audioheritage.org/vbulletin/showthread.php?t=14369

I just spoke to JBL Pro tech support, who inquired of engineering.

Answer: "The information is proprietary...."

There are valid reasons why they are made the way they are.

Performance is one of them. Safety is another one...and there are others, too.

If you've had the opportunity to hear the Everest II, and speak with the designer, all doubts would be laid to rest.

My point for starting this thread was to save frustration and cash for those with some hope of cheap Be diaphragms.

Read the Brush-Wellman papers on working with this stuff and you'll learn why it can't be cheap.....it's pretty high metallurgical science.

Zilch
04-25-2007, 02:19 PM
There are valid reasons why they are made the way they are.And that would be how, Edge?

[Presuming you're at liberty to tell us.... :thmbsup: ]

scott fitlin
04-25-2007, 02:28 PM
Not exactly true...

No. TAD deposits / fogs their Be onto a Cu substrate and then dissolves the Cu away leaving a pure Be diaphragm.Thanks Bo.

I was just asking, cause I didnt really know. I do know of the process you describe, they call it sputtering, and TAD made a big deal about how they do it, because when other companies began using Be, they said the others cold rolled it, rather than the vacuum deposit process.

edgewound
04-25-2007, 03:50 PM
And that would be how, Edge?

[Presuming you're at liberty to tell us.... :thmbsup: ]




Performance is one of them. Safety is another one...and there are others, too.



:thmbsup:

Zilch
04-25-2007, 03:53 PM
No, no. How they are MADE, Edge! :p

Titanium composite or pure Be foil?

edgewound
04-25-2007, 05:56 PM
Be foil
.

mech986
04-25-2007, 06:13 PM
They "Be" foil :D :applaud: Good one!

Bart

Zilch
04-25-2007, 06:23 PM
So, the information on PSW, allegedly from Dave Wheeler, is bogus? :dont-know

Steve Schell
04-25-2007, 09:59 PM
I have been told that the TAD Be diaphragms are made by forming a copper diaphragm pressing, vapor depositing a layer of Be on it, then chemically eroding way the copper to produce the finished diaphragm. No wonder they cost so much.

The Brush Wellman supplied JBL Be diaphragms are pressed from sheet Be, possibly alloyed with something else to aid in the forming process... not sure about this.

edgewound
04-26-2007, 10:14 AM
So, the information on PSW, allegedly from Dave Wheeler, is bogus? :dont-know

Dave is a great guy. He's a Customer Service Rep, not a JBL Design Engineer.
Dave might not really know the whole story...and...it's possible he was misquoted. Geez...that never happens on the internet:p .

Go back up to my first post and click on the Brush-Wellman link.

Read up on their Be papers.

Then...go the the reprints form "Voice Coil" magazine and read up.

After that, you'll know more than most.;)

johnaec
05-06-2007, 02:22 PM
There is a new thread at ProSoundWeb with corrections forwarded from JBL's Dave Wheeler on beryllium diaphragms: http://srforums.prosoundweb.com/index.php/t/22978/8370/

Apparently the 2435HPL diaphragms ARE pure beryllium, or at least 98% - no titanium whatsoever. More details in that thread...

John

scott fitlin
05-06-2007, 02:26 PM
I have been told that the TAD Be diaphragms are made by forming a copper diaphragm pressing, vapor depositing a layer of Be on it, then chemically eroding way the copper to produce the finished diaphragm. No wonder they cost so much.

The Brush Wellman supplied JBL Be diaphragms are pressed from sheet Be, possibly alloyed with something else to aid in the forming process... not sure about this.Yeah, when JBL introduced drivers with Be diaphragms TAD made a big deal about the fact that they sputter their material to form the diaphragm, and everyone else cold rolled them.

The vacuum deposition method is considerably more expensive to do.

loach71
05-06-2007, 05:11 PM
A sad corollary to globalization.
Just like the melamine scandal.
Caveat emptor...:(

edgewound
05-07-2007, 10:59 AM
There's a couple of points to be made here.

Firstly, is the speed at which mis-information travels on the internet, especially when the dissemination of the information comes from further than firsthand communications...in other words speaking directly with the source, and quoting said source in most accurate context...which would be the truth.

Secondly, if this country continues to rely on lesser industrialized non-democracies to supply us with goods that are far less costly and substandard quality-wise than domestically produced goods....we will continue to be swindled, poisoned, and ultimately the whole population potentially killed off by organizations that simply want to do it cheaper... and do not adhere to any ethical standards regarding product safety and intended use.

People in Panama were killed by ingesting what were supposed to be human medicines containing glycerine. Turns out the meds contained glycol..yep....antifreeze. A Chinese company is the source.....OOPS!

Here's the story:
http://www.msnbc.msn.com/id/18518915/

4313B
05-07-2007, 11:21 AM
Firstly, is the speed at which mis-information travels on the internet, especially when the dissemination of the information comes from further than firsthand communications...in other words speaking directly with the source, and quoting said source in most accurate context...which would be the truth.It also helps if the deliverers of information aren't goofballs posting gushing gagfests like "simply the best speaker engineer that ever lived". I took a few minutes to read over that website and now I don't feel so bad about this one. Don is right - over time these things just degenerate into a morass of bullshit full of people with bankrupt lives.

Thom
05-07-2007, 03:05 PM
This will probably get me shot by any one but Zilch because if he goes "commie" hunting he'll probably find real ones carrying signs on his corner. I've been to Berkly. One of the problems of capitalism is the most important thing is to get people to buy your widget. If you have to make it better for them to buy it, you make it better. If you have to say it is made of a specific material for them to buy it then you say it is. If you can get fined if you say it and it isn't true, you figure what the fine would cost. How likely you are to get caught. What it would cost to really make it from that material and you make a decision. This is not an accusation aimed directly at JBL. I have no information about them and I'm not saying that they do this but big business does do this on a regular basis. With some other economic system, perhaps what products are and what they are made of, could just be factually stated. You wouldn't hear "proprietary information" Someone running a sound company could actually have as their goal, to make the best sound as opposed to the best selling. Today if your goal as a business is to make the best product and you take your eye off the money you will probably go broke.

scott fitlin
05-07-2007, 03:14 PM
This will probably get me shot by any one but Zilch because if he goes "commie" hunting he'll probably find real ones carrying signs on his corner. I've been to Berkly. One of the problems of capitalism is the most important thing is to get people to buy your widget. If you have to make it better for them to buy it, you make it better. If you have to say it is made of a specific material for them to buy it then you say it is. If you can get fined if you say it and it isn't true, you figure what the fine would cost. How likely you are to get caught. What it would cost to really make it from that material and you make a decision. This is not an accusation aimed directly at JBL. I have no information about them and I'm not saying that they do this but big business does do this on a regular basis. With some other economic system, perhaps what products are and what they are made of, could just be factually stated. You wouldn't hear "proprietary information" Someone running a sound company could actually have as their goal, to make the best sound as opposed to the best selling. Today if your goal as a business is to make the best product and you take your eye off the money you will probably go broke.Marketing 101, right?

:D

edgewound
05-07-2007, 03:17 PM
Thom,

I tried to read what you just wrote....and try to understand it.

American companies can be sued out of existance if they knowingly lie to their customers. It's called "fraud", and last I heard it is illegal in this country to totally misrepresent your product.

The ProSound Web thread on JBL 2435's was pure and simple stupidity.

China plays by a different set of rules than we do. Just look at the piracy of intellectual property vis a vis DVD movies and Microsoft software just to name two.

When it comes to selling diaphragms that are purported to be beryllium and they are tested to be devoid of beryllium that's pure and simple fraud, which is a crime in this country.

When a chemical company sells a poisonous chemical that's misrepresented as an ingredient for medicine, that's murder.

At the risk of going too far off topic in this thread, I'll stop here.:D