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**Dirk** · 06-10-2009, 04:31 PM

Re: The Whole Truth About Beryllium Diaphragms

Mowry, you've got all of 8 posts behind you and you post a link to a random zip file? Yeah, this doesn't look fishy... :D

However, in mowry's defense, I just downloaded it and opened it on my Linux box. TrendMicro OfficeScan didn't freak on my XP machine, either. Seems to be what he says it is.

**MSaturn** · 06-10-2009, 04:34 PM

Re: The Whole Truth About Beryllium Diaphragms

Bogusium? That can't be good.

It's not a virus, btw (no offense, but posting .zip files is sort of sketchy)

**shawn_a** · 06-10-2009, 04:36 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by Dirk View Post

Mowry, you've got all of 8 posts behind you and you post a link to a random zip file? Yeah, this doesn't look fishy... :D

However, in mowry's defense, I just downloaded it and opened it on my Linux box. TrendMicro OfficeScan didn't freak on my XP machine, either. Seems to be what he says it is.

Thanks for throwing yourself on a potential grenade, Dirk. Even on a Mac I don't tend to download untrusted material. And yep, the first thing I looked at was how many posts Mowry had under his belt. I don't like to be untrusting but after getting word that my debit card had been compromised (no loss, thankfully) I'm not exactly in the mood to be had.

shawn

**jkrutke** · 06-10-2009, 05:57 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by Dirk View Post

Mowry, you've got all of 8 posts behind you and you post a link to a random zip file? Yeah, this doesn't look fishy... :D

However, in mowry's defense, I just downloaded it and opened it on my Linux box. TrendMicro OfficeScan didn't freak on my XP machine, either. Seems to be what he says it is.

Steve Mowry is a geniune industry professional and this post seems legit.

Summed up, he has a concern about fake Beryllium.

Of particular interest to me is the mention that Usher originally sourced beryllium from a diaphragm manufacturer that had a low percentage of beryllium content. Then in February of this year, they switched to a different dome supplier with higher beryllium content. I have to wonder which one I just tested, as it was barely any different from the Usher aluminum dome.

It's all interesting reading, but I have to sit and wonder what Steve's real motivation is behind publishing and pushing this article far and wide.

My own personal view is that there's absolutely nothing special about any beryllium speaker, be it pure or less that 1% beryllium content. I'm taking that stance until it's proven to me otherwise. There's obviously a lot more that goes into driver design than diaphragm material selection.

The whole rah-rah started mostly because of a late 70's Pioneer speaker system that was well received. There was a mention of this in Steve's article. Unfortunately, this mysticism over beryllium is generated by nothing more than people subjectively evaluating a system rather objectively evaluating an individual driver. It's a common problem that still is rampant today.

Just my $.02.

**MSaturn** · 06-10-2009, 06:03 PM

Re: The Whole Truth About Beryllium Diaphragms

Indeed, accuton's diamond diaphragms are also dubious.

Ribbon tweeters are dubious.

Large planar speakers are dubious.

I have a degree in marketing, and there's a definite reason Bose has such market share - it sure as hell isn't their R & D department. Such marketing hoo-hah and a lack of respect for testing - and dare I say SCIENCE - is insidious at best.

**jkrutke** · 06-10-2009, 06:50 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by MSaturn View Post

Indeed, accuton's diamond diaphragms are also dubious.

Well I don't know about Accuton, but a while back I had a B&W diamond tweeter run through a materials lab and it was indeed diamond. Or at least, DLC (diamond-like carbon) on a platinum base.

**MSaturn** · 06-10-2009, 06:55 PM

Re: The Whole Truth About Beryllium Diaphragms

Oh, I was referring to usefulness. I can't hear much past 20Khz - I'm sure most posters here can't - and one of Accuton's selling points is "response to 100KHz!" or some business.

My gripe is the supposed superiority of these materials to standard varieties.

A tweeter better do my taxes at $800 ...

That said, you didn't do any testing on the B&W besides the materials, did you? .. I suppose you couldn't say anyway heh

**ctbowman** · 06-10-2009, 07:32 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by MSaturn View Post

Oh, I was referring to usefulness. I can't hear much past 20Khz - I'm sure most posters here can't - and one of Accuton's selling points is "response to 100KHz!" or some business.

My gripe is the supposed superiority of these materials to standard varieties.

A tweeter better do my taxes at $800 ...

That said, you didn't do any testing on the B&W besides the materials, did you? .. I suppose you couldn't say anyway heh

If I remember correctly he did test the tweeters but agreed not to share the results in exchange for the privilege to do so. Something he swore he would never do again. I don't remember where I read that....

**envisionelec** · 06-10-2009, 07:54 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by MSaturn View Post

Oh, I was referring to usefulness. I can't hear much past 20Khz - I'm sure most posters here can't - and one of Accuton's selling points is "response to 100KHz!" or some business.

My gripe is the supposed superiority of these materials to standard varieties.

A tweeter better do my taxes at $800 ...

That said, you didn't do any testing on the B&W besides the materials, did you? .. I suppose you couldn't say anyway heh

I have a 28 year old friend whose hearing extends well above 20kHz, with a rising response, no less (verified by hearing tests). So, there is a market. :rolleyes:

**Pete Schumacher** · 06-10-2009, 08:18 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by envisionelec View Post

I have a 28 year old friend whose hearing extends well above 20kHz, with a rising response, no less (verified by hearing tests). So, there is a market. :rolleyes:

So, what kind of music does Rover find the most relaxing? :D

**augerpro** · 06-10-2009, 08:38 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by jkrutke View Post

I have to wonder which one I just tested, as it was barely any different from the Usher aluminum dome.

Mowry just posted a data sheet from Sonic showing 88% Titanium and a miniscule amount of Be. Maybe the ones you just tested were Ti?

I agree with the comments about Be being the holy grail too. If I were to choose, it would be something with both high stiffness and high intrinsic damping. The Accuton ceramics come close. I think the Metal Matrix family probably has a lot to offer. And I don't mean the anodized stuff Harman et al call MM. Or some kind of metalized foam.

**Pete Schumacher** · 06-10-2009, 09:15 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by augerpro View Post

Mowry just posted a data sheet from Sonic showing 88% Titanium and a miniscule amount of Be. Maybe the ones you just tested were Ti?

I agree with the comments about Be being the holy grail too. If I were to choose, it would be something with both high stiffness and high intrinsic damping. The Accuton ceramics come close. I think the Metal Matrix family probably has a lot to offer. And I don't mean the anodized stuff Harman et al call MM. Or some kind of metalized foam.

I wonder how an exponentially curved cone, fashioned from Al, Mg, Ti, with a thin layer of flexible plastic to damp cone resonances, would perform. Get the stiffness and pistonic action of the metal cone with better tamed resonances perhaps. I wonder if it's been attempted. I'd be amazed if it hadn't. I just don't have that many truly original ideas . . . :rolleyes:

**jkrutke** · 06-10-2009, 09:18 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by ctbowman View Post

If I remember correctly he did test the tweeters but agreed not to share the results in exchange for the privilege to do so. Something he swore he would never do again. I don't remember where I read that....

You're thinking of the Accuton diamond dome which I made that agreement for. And then I swore I would keep results secret again... until the new ScAR and Vifa neo woofers came along. :D

I never did test the B&W diamond. I just had a broken one sent to me once so I could inspect the motor and overall design. (impressive) I dropped some dome fragments in an envelope and sent them out to get analyzed.

Mowry just posted a data sheet from Sonic showing 88% Titanium and a miniscule amount of Be. Maybe the ones you just tested were Ti?

They were grayish-purple colored. Still not sure, but if they are fake I'd say Usher did a good job with the color match to the old pioneer domes.

**rone** · 06-10-2009, 11:14 PM

Re: The Whole Truth About Beryllium Diaphragms

Originally posted by mowry View Post

After a year of research I uncovered and compiled an interesting story from within the loudspeaker industry. You can download my manuscript here, http://www.s-m-audio.com/truth.zip

...So the moral of the story is caveat emptor.

John, I was thinking those domes you speak of were probably Yamahas, Pioneer was more famous back then for their HPM's (cylindrical piezos), then I searched:

Pioneer of Pioneer CS-755 specifications

http://audio-database.com/PIONEER-EXCLUSIVE/speaker/cs-755-e.html

Pioneer, Pioneer, CS-755

I wonder if this was a "me too" speaker based on the yamahas.

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