The Beryllium Myth

[Ian Mackenzie]

I started this thread by pulling posts from a thread where this Be conversation was going off topic.

Widget



Good to see this thread is still alive.


I must say..I prefer beryliium..with a momentary lapse of reason "even in the quietest moments"

iMac

[Ian Mackenzie]

The motive here is that spurious noise or resonances (from drivers) and distortion from equipment make people want to Eq or treat their room. :dont-know

The Be drivers are remarkably quiet. It helps if you can isolate what the problems are. Then dealing with them is much easier.

[Ian Mackenzie]

Ian,

Be is best ! anything else is a fools overture ;)



Rich

I think that is a bit strong.

Besides, be is a rare metal..there might not be enough to go around!

[KCCT82]

The Be drivers are remarkably quiet. It helps if you can isolate what the problems are. Then dealing with them is much easier.


Don't know if the problems are from Be or not drivers (no knowledge in this area), but my TAD 2002 driver on TAD 2002 horn was much quieter than my BMS coaxial driver on TAD 4001 horn. Everything else in the setup stayed the same. Next would be to try the 2452H-SLs :)



Besides, be is a rare metal..there might not be enough to go around!


Might be one reason why they have the Be/Al alloy, another one more obvious being the cost... Anyone got a chance to hear these kind of diaphragms/domes?

[Mr. Widget]

...but my TAD 2002 driver on TAD 2002 horn was much quieter than my BMS coaxial driver...Quieter? Please explain.


Might be one reason why they have the Be/Al alloy, another one more obvious being the cost... Anyone got a chance to hear these kind of diaphragms/domes?Who is making Be/Al alloy drivers?


Widget

[KCCT82]

Quieter? Please explain.


At the listening position I could hear noise coming from the BMS drivers, thought they were from ground loops or cables being too close :blah: When I switched to TAD 2002 Be drivers, noise reduced to only being audible when I stick my head in front of the horn. Nothing was different except for the drivers/horns and the extra extra long banana plugs provided by TAD. Definitely quieter background when listening to music. These are just subjective listening impressions, the "quieter background when listening to music" might just be perceived to be so because of the extra detail I got from the Be drivers. (Be careful buying used 2002s, they need those extra long banana plugs, regular ones don't plug in deep enough into the driver. No binding posts either, you WILL be stuck w/o them!)


Another thing to note is that although there was noise from the BMS, it reduced a bit when I switched from BMS fiberglass horns (2236) to TAD 4001 wood horns. I don't know how that's possible, but I heard the difference. Again, no measurement to support, but I did use the same BMS horns for 3 years before switching to 4001 horns.




Who is making Be/Al alloy drivers?



Well... I dont know if anyone IS making drivers, but there is a Be/Al alloy for audio use. I was hoping someone else could tell me if there are ready made products using Be/Al ;)


Some info here:


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

[KCCT82]

Hmm... quick google search... KRK studio monitors use them ;)

"Reproducing the top end is an all-new, 1-inch, inverted-dome AlBeMET tweeter. AlBeMET is a composite material comprising aluminum and beryllium, which offer extremely flat HF characteristics all the way out to 30 kHz within ±1 dB."

http://mixonline.com/gear/reviews/audio_krk_expos_eb/

Umm... moderator? should we move this to another thread? Thx

[Ian Mackenzie]

KCCT82,

Any one who owns Tads or JBL Be drivers know exactly what you are saying. If they dont they probably have hearing damage.

[KCCT82]

Any one who owns Tads or JBL Be drivers know exactly what you are saying. If they dont they probably have hearing damage.


Right... and anyone who had done room treatments would know exactly what you are saying too. If they dont they too probably have hearing damage. Widget asked, I answered. I apologize for going off topic, but like I said in the earlier post, moderators can move it if they feel the need to.

[Mr. Widget]

KCCT82,

Any one who owns Tads or JBL Be drivers know exactly what you are saying. If they dont they probably have hearing damage.I own TADs and have heard quite a few JBL Be drivers and I haven't a clue as to what you are talking about. I had my hearing checked about a year ago and I was still able to hear quite well... the doctor was surprised how well.

Are you saying that you think that Be is inherently quieter?

Lower distortion, sure, better damped, sure, higher resonance and break up, you bet, but quieter?


Widget

[Mr. Widget]

At the listening position I could hear noise coming from the BMS drivers, thought they were from ground loops or cables being too close :blah: When I switched to TAD 2002 Be drivers, noise reduced to only being audible when I stick my head in front of the horn.Not knowing all the facts here, I'd speculate that this is due to a resonance peak in the BMS that is not present in the TAD. This peak will play system noise (or musical content) at a higher SPL level... think narrow band EQ up top with 10db of gain. Changing horns could also affect this as one horn may roll off more than another in it's on axis response.


Widget

[KCCT82]

Not knowing all the facts here, I'd speculate that this is due to a resonance peak in the BMS that is not present in the TAD. This peak will play system noise (or musical content) at a higher SPL level... think narrow band EQ up top with 10db of gain.


Mr. Widget- that sounds convincing... is there a ball park answer to what freq. polyester diaphragms break up at? Is there a way of telling where it's at from the response curves? Thx

[Ian Mackenzie]

I own TADs and have heard quite a few JBL Be drivers and I haven't a clue as to what you are talking about. I had my hearing checked about a year ago and I was still able to hear quite well... the doctor was surprised how well.

Are you saying that you think that Be is inherently quieter?

Lower distortion, sure, better damped, sure, higher resonance and break up, you bet, but quieter?


Widget

Have you heard of Cone Cry?

Probably not. Its Loudspeaker talk.

A term driver engineers use to describe the behaviour of rigid cone drivers, notably kelvar when they are pushed at high output levels.

I know you are not technical but every driver known to Man makes a noise other than produced by the signal put into it. Some more than others.

Therefore if you subtract the output produced by the input signal you are left with the noise of the diaphragm from self induced vibrations during the signal and after the signal stops.

Some people woud say, ah but that is distortion. Well some of it probably is from the flux modulation and other things. But if you account for that what you you left with? Something's making a bloody lot of noise. There are various reasons for that. I dont want to go there now because I dont have all day to explain it.

As an analogy if you jump in a car and play a cd you will hear the Cd and depending on the car a lot of road noise from the types and the body of the car. Some tyres and car body's are alot quieter than others by the way.

Its a just term I and a number of others use to distinguish between Be drivers and the behaviour of other types of drivers.

[Mr. Widget]

Have you heard of Cone Cry? Ok, Mr. Technical, I think your "technical" term cone cry is refering to:

Lower distortion, sure, better damped, sure, higher resonance and break up, you bet, but quieter?Good grief.


Widget

[Mr. Widget]

Mr. Widget- that sounds convincing... is there a ball park answer to what freq. polyester diaphragms break up at? Is there a way of telling where it's at from the response curves? ThxI have no experience with polyester diaphragms, however being that they are not as rigid per gram as AL or Be, I'd assume that their mass break point is lower in frequency (for a given diaphragm size). Take a look at this document from JBL. It covers the subject really nicely.

http://www.audioheritage.org/vbulletin/showthread.php?t=4410

As for your frequency plots... they show exactly what I was talking about. Those peaks in the area that I shaded green are most likely all made up of ringing and other nonlinear products as well as being higher in amplitude. I imagine this is exactly what you were hearing. You can also see how the impedance has resonance related issues and the significant increase in distortion.


Widget

[grumpy]

Distortion, resonance, frequency dependent sensitivity...

all could certainly result in the perception of what would seem "quieter"
(which is rather ill-defined). I don't believe anyone is doubting this effect.
Arm waving and name calling (effectively) seems counter productive.

-grumpy (yes, I'm "technical")

[Mr. Widget]

I don't believe anyone is doubting this effect.
Arm waving and name calling (effectively) seems counter productive.I think Ian's "technical" comments were referring to my sometimes showing lack of respect for All Technical Services Company aka: Altec. :rotfl:


Widget

[Ian Mackenzie]

Muhahahah.

I did not invent the term but is has appeared independently and been used on a number of other horn/ audio forums by those discussing the merits of beryillium based drivers.

I guess you can call them out as idiots if you like.

It matters not because so few people here or elswhere have exposure to such devices .;)

[richluvsound]

Ian,

I can only agree with Merlin on this " in comparison everything else sounds broken" or words to that effect.
I can't back it up with graph, but I know of people that can and have done.

Rich

[Mr. Widget]

No myth that beryllium is a superior material for mid and HF drivers, but there is a bit of myth and lore surrounding it.

As for the Be/AL composites, I think they are AL drivers using a Be coating to give them a bit of the "Emperor's New Clothes" effect. I was recently talking with Andrew Jones, the designer of the TAD home speakers, and he told me that they were introducing a new line of less expensive speakers in the TAD/Pioneer EX line that used a ceramic composite tweeter. In his words, "if beryllium is two times better than aluminum, then this ceramic composite was one and a half times better." And previously when they developed the midrange driver for the EX series, to reduce the cost of the 6" beryllium driver used in the TAD they went to a 5" magnesium cone. In both of these cases I am sure if a Be/AL composite was superior that is what they would use.


Widget

[KCCT82]

if beryllium is two times better than aluminum, then this ceramic composite was one and a half times better." And previously when they developed the midrange driver for the EX series, to reduce the cost of the 6" beryllium driver used in the TAD they went to a 5" magnesium cone. In both of these cases I am sure if a Be/AL composite was superior that is what they would use.



Very good info and explaination on the BMS graphs, thx Widget:applaud:

[KCCT82]

Hey Ian, nice pictures!:applaud: I couldn't find it in the links, but I suppose these are Be drivers as well?

[merlin]

Ian,

I don't think all Be drivers are created equal ;)

For instance, to my ears the 435be was something of a disappointment. Sorry to have to say that but on the other hand, I was really impressed by the 476be in the Everest 2.

The TAD 2002 has also really surprised me. It has such glorious tone - sounding reminiscent of the Vitavox S2 without the ringing and vintage folklore crap.

When I used the term "made the others sound broken" it was in response to what I thought of brand A in comparison with brand B. I suspect you can fill in the blanks.

[richluvsound]

Ian,

I don't think all Be drivers are created equal ;)

For instance, to my ears the 435be was something of a disappointment. Sorry to have to say that but on the other hand, I was really impressed by the 476be in the Everest 2.

The TAD 2002 has also really surprised me. It has such glorious tone - sounding reminiscent of the Vitavox S2 without the ringing and vintage folklore crap.

When I used the term "made the others sound broken" it was in response to what I thought of brand A in comparison with brand B. I suspect you can fill in the blanks.

Merlin,
sorry mate ,I hope I didn't quote you out of context :o:

[Mr. Widget]

I dont think we want a brand war here.There is no need to.

As you seem to elude to in your confusing post, there is no one right answer.


Widget

[mikebake]

There is no need to.

As you seem to elude to in your confusing post, there is no one right answer.


Widget
I know you meant allude, but maybe elude was better.........

[speakerdave]

. . . or etude . . .

[Mr. Widget]

I know you meant allude, but maybe elude was better.........Oops! :o:

Where's the emoticon with egg on it?


Widget

[Zilch]

:scold: Let's not be pissing Ian off until AFTER he tells us about the 2435HPL on 1.5" horn, now....


:D

[Mr. Widget]

:scold: Let's not be pissing Ian off until AFTER he tells us about the 2435HPL on 1.5" horn, now....


:DHaven't you tried that combo out yet?

Was it quieter than an L100's LE25? :duck:


Widget

[Zilch]

Was it quieter than an L100's LE25? :duck:It's the intended use thing again: L100's for practising Chuck Berry moves; "quiet's" not part of the equation.... ;)

[scott fitlin]

Ian,

I don't think all Be drivers are created equal ;)

For instance, to my ears the 435be was something of a disappointment. Sorry to have to say that but on the other hand, I was really impressed by the 476be in the Everest 2.

The TAD 2002 has also really surprised me. It has such glorious tone - sounding reminiscent of the Vitavox S2 without the ringing and vintage folklore crap.

When I used the term "made the others sound broken" it was in response to what I thought of brand A in comparison with brand B. I suspect you can fill in the blanks.DITTO!

UNTIL " I" was taught "HOW" to setup and use my TADS they sounded awful to me. Little did I realize what the TAD,s were showing me, was all my electronics, amps, etc, upstream in the signal path.

BUT, ONCE you DO know how to get these puppies to work correctly, THERE JUST IS NO GOING BACK!

NOW, everything I loved for years and years, DOES sound broken and hashy to me.

About TAD Be, compared to other brands of Be, well, there are defintely differrent manufacturing processes used by different companies. WHY? Who knows? Does different manufacture processes make any audible difference? I never did any measurements, but, my ears prefer properly setup TAD drivers to all others. Except Steve Schell's Cogent drivers, because I have never heard them.

I won't knock other brands of drivers utilizing some form of Be diaphragms, but, I just look at the fact that TAD has been using Be since`75. Pretty much before all others, and for the longest, till any other manufacturer got into the " BOUTIQUE " Be game, at all! If my memory serves, Be became a "boutique" SPECIALTY ITEM ITEM OF THE " YOU ARE NOBODY, UNLESS YOU HAVE Be" class in the 90,s! Again, IT WASN'T "LBJ" THAT DID IT EITHER! More like JM lABS in their Grand Utopia speakers. And, I believe JM LABS engineers were looking for a way to compete with B & W,s marketing hype of their exclusive " BOUTIQUE " diaphragm material, " DIAMOND DUST COMPOSITE, they were/are using for their TWEETER diaphrams!

I have heard JBL Be drivers, I wont knock them., but I will say, sonically thet are differrent from the TAD sound.

The funniest thing about TAD drivers, is originally, they are in fact designed by Bart Locanthi, the JBL engineer who designed the acoustic lens, the 375, etc!

HYPE? MAYBE! But, IRONIC, TOO! TAD TOOK A JBL ENGINEER,and GAVE HIM CARTE BLANCHE TO DESIGN AS HE SAW FIT TO, AND THEN TURNED IT OUT TO THE WORLD, FROM " MADE in JAPAN"!!!!!!!!!!!!!!!!!!!!!!

BUT, know this, IT WAS HYPE ENOUGH FOR JBL TO JUMP INTO THE Be Game too! Only, over 20 YEARS AFTER!

[Robh3606]

Here something about the Be/Al diaphrams

http://www.berylliumproducts.com/documents/Beryllium+Speakers.pdf

Rob:)

[Predrag Dukic]

I think that is a bit strong.

Besides, be is a rare metal..there might not be enough to go around!

In Fact Be is not that rare... And it takes a gram or so in every dia to be produced. The problem is Be toxicity.... It is treated as hazardous material, not exactly as plutonium, but close.
Every machine tool must be isolated with HEPA filters, workforce needs high health insurance and that adds to the price, not the material itself...

[Fort Knox]

I was a draftman during the Cold War and the military
used Beryllium copper type electrical switches for their spring-like
quality..vary hard mat'l..long duty life

[ivica]

Here something about the Be/Al diaphrams

http://www.berylliumproducts.com/documents/Beryllium+Speakers.pdf

Rob:)

Updated links:

http://materion.com/~/media/Files/PDFs/Electrofusion/PLS2011PAPERFINAL.pdf
http://materion.com/~/media/Files/PDFs/Electrofusion/TDS2003_BeX4008_16.pdf
http://materion.com/~/media/Files/PDFs/Electrofusion/TTB002_TuningForks.pdf
http://materion.com/~/media/Files/PDFs/Electrofusion/EQF3023_PrecisionDiaphragm.pdf

Regards
Ivica

[4313B]

They forgot to add in magnesium. :D

Thanks for the links. :)

Interesting how JBL further damped the BE diaphragm in the 435BE with aquaplas.

Apparently still no news on 1.75" BE diaphragms.

Anyone else notice their credits?
JBL is a registered trademark of Harmon International Industries, Inc.

[SEAWOLF97]

IRONIC, TOO! TAD TOOK A JBL ENGINEER,and GAVE HIM CARTE BLANCHE TO DESIGN AS HE SAW FIT TO, AND THEN TURNED IT OUT TO THE WORLD, FROM " MADE in JAPAN"!!!!!!!!!!!!!!!!!!!!!!

that's somewhat what JBL did to Ed May ..when he turned 60 , hit the "mandatory retirement age" and was gone....Marantz snapped him up, gave him carte blanche, built a lab for him and he set out to best the L100.

[frank23]

that's somewhat what JBL did to Ed May ..when he turned 60 , hit the "mandatory retirement age" and was gone....Marantz snapped him up, gave him carte blanche, built a lab for him and he set out to best the L100.

And with what did he best the L100? I am curious to know what Marantz put on the market.

[SEAWOLF97]

And with what did he best the L100? I am curious to know what Marantz put on the market.

HD440 (http://www.classic-audio.com/marantz/HD440.html)
HD550 (http://www.classic-audio.com/marantz/HD550.html)
HD660 (http://www.classic-audio.com/marantz/HD660.html)
HD770 (http://www.classic-audio.com/marantz/HD770.html)
HD880 (http://www.classic-audio.com/marantz/HD880.html)


Ed left JBL in 1976, just as detailed design was just beginning. He joined Marantz Superscope to become their head of loudspeaker design. A custom design facility was built specifically for him. He used it to turn out three complete lines of loudspeakers in very short order. However, this was the last loudspeaker work he would perform. Edmond May passed away suddenly in 1980 while still employed at Marantz.


http://www.audioheritage.org/html/people/may.htm


In 1976, Edmund (Ed) May, one of the
most respected speaker designers at
JBL, joined Marantz and was given the
charge of developing a speaker line to
complement the company’s other high
end offerings. Superscope built a new
R&D facility for May to work in. The
resulting “HD” speakers were highly
praised and enhanced the brand’s reputation
substantially. Unfortunately, May
died in 1980 and later design efforts
met with considerably less success and
all efforts to design and market loudspeakers
ceased.

[4313B]

I didn't care how any of those HD systems sounded. I ran my loudspeakers without grilles back then and the transducers were too goofy looking for my tastes. ;)

My uncle had two pair though that he ran off a Marantz Receiver in Quad. He loved them and the best part was that they made him happy.

[BMWCCA]

Anyone else notice their credits?
JBL is a registered trademark of Harmon International Industries, Inc.
I had to go back and look. At first I thought you were implying Harman didn't know how to spell their own name, not that that should surprise anyone!

(As a magazine editor for ten-years for a BMW-centric book with its proof-reading issues compounded by frequent references to harman/kardon sound systems as well an iconic individual with the name of Harmon whose last name also caused grief for this ex-Fisher 400 owner (Fischer), my eye is sensitive to the frequent incorrect choice of words. And yet I ran right by it.)