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Sorry!
Contact
www.truextent.com
for more info
Deleted was a detailed comparison between a JBL 476BE and a JBL 2451 equipped with truextent diaphragm. Both on an Everest 2 horn clone.
Plus a short distance picture of a truextent diaphragm.
Yep. I'm sure all the folks on this forum are overjoyed that I got stuck with a $5,600 pair of 476Be's... yet another JBL rendered worthless. :barf:
Needless to say, I'm done funding other people's DIY projects...
OK what's going on??
Rob:)
The information is available on the Internet:Quote:
Originally Posted by Guido
Truextent brand SSX beryllium compression driver diaphragm datasheet
$790 each for one or two
$745 each for three or more
And there will probably be promotions in the next thirty to sixty days. So get them cheaper at that point.
Can you speak specifics for those who aren't behind the scenes enough to know what the obliqueness means.Quote:
Originally Posted by 4313B
What? Did someone grab a pair of JBLs at a reduced fee
and then make low costs clones offshore (or something equally rude and disturbing).
It goes back to another forum member denigrating the 476Be last month and stating that it was grossly overpriced because Be diaphragms for all 4-inch JBL compression drivers were coming out in a month or two. Nevermind that the TAD's are even more expensive than the JBL's... or that the 476Be's cost what they cost to manufacture because they are made in the U.S.A. The 476Be costs what it costs. JBL isn't trying to put one over on anyone. It's just irritating because I've gotten about as many complaints about the cost of 476Be's as I've gotten about the cost of recone kits. People want free shit. It's a buy one get one free society.
It will cost $1,580 to get reasonably close to the 476Be performance using these diaphragms in any 4-inch JBL compression driver.
Only close. The 476Be has some features that makes it special. There is absolutely no rising impedance up to 20k with a 47Be. It's the copper sleeved pole.Quote:
Originally Posted by 4313B
But those truextent diaphragms (Made in USA) are reality and it makes no sense to try to stop people posting about it.
There will be no more information from me.
But others will come.....
Meaningless drivel to wannabees.Quote:
Originally Posted by Guido
Yep. It's a Walmart World. :yes: And I don't think anyone is trying to stop anyone from posting about them. You deleted your posts of your own volition. You should ask a moderator to restore them.Quote:
Originally Posted by Guido
Obviously the 476Be is still a very desirable driver despite what wannabees will invariably blog on about. You picked it to compare to for a reason and I find it rather irritating, especially with the Everest II horn clone thing. What is the objective here? I didn't realize that I supplied you with a pair so that you could cook up this comparison. When I bend over backwards to supply you guys with this stuff I'm doing it because I mistakenly think you have a personal interest in owning something really nice for personal use. My mistake. It all ends right now.
What are you talking about?? No one said a word or even responded to your posts and you deleted them yourself. The times the posts went up are right there. That's why I asked what was going on.Quote:
But those truextent diaphragms (Made in USA) are reality and it makes no sense to try to stop people posting about it.
Rob:)
Undelete them so everyone can hear the difference. :rotfl:Quote:
Originally Posted by Guido
Nothing has changed since my discussion with Doug and Jerry several years ago with respect to putting the Be diaphragm in the older JBL cores. Quite obviously, none of them will ever be a 476Be, but they will be "close enough" for some people. That's just how it is. And given that the 476Be is nearly impossible to get outside of an E2...
The fact that these diaphragms are going to be available is fantastic. I've never felt that the non-aquaplased aluminum diaphragms were worth the extra cash over the aquaplased titanium diaphragms. The Mg and Be diaphragms are worth the extra cash.
I knew that was coming. It only took a day after the initial post.Quote:
These Truextents are very pricey though.
It's easier this way
The graphs are similar on H9800 or H4338 Horns.
Oh, these diaphragms are NOT pricey. Put them in a nice 1,5" JBL Driver and you end up with an absolute SOTA Driver. WORLD CLASS.
Can you do some graphs on the $10 waveguides? I think that's where the real interest lies.Quote:
Originally Posted by Guido
The H9800, H4338, 435Be, 476Be, 045Be, 1500AL, 1501AL, etc are intended only as replacement parts for owners of the 4338, K2 and E2 loudspeaker systems.
Sorry I don't have any $10 waveguides.
H9800 and EV2 Horn clones are available. No idea why so few members use them :dont-know
Quote:
Originally Posted by 4313B
FR is one thing. The impedance looks quite a bit nicer on the 476Be.
Have you any CSD and distortion measurements to post?
-Tim
A comparison with the traditional titanium (aquaplassed or not) or aluminium diaphragms in the same measurement conditions would also be nice :bouncy:
This is a post for information only. These dias are available and they are worth a try.Quote:
Originally Posted by timc
All other measurements you'll have to do for yourself. It's anyway better to try and listen on your own.
I 100% agree with that, but to compare quality with the 476Be (or even TAD-4003) It would be nice to see more measurements.Quote:
Originally Posted by Guido
It's quite an expensive experiment you are sugesting ;)
-Tim
Because they probably cost money...Quote:
Originally Posted by Guido
Guido, have you tried to put the Truextent dia in the 476 ? :D :D :D
Give me an effing break!!! You'd have to have rocks in your head to pull apart a $5,600 pair of drivers just to eff around with them...Quote:
Originally Posted by pos
I rue the day I sold a pair to Guido. :banghead: It was an effing favor...
Keep cool 4313b, that was just an effing joke ;)
They are in good hands, no worrys. And you know that!Quote:
Originally Posted by 4313B
I will not pull apart the 476Be's. Well, maybe when I blow the dia one day.Quote:
Originally Posted by pos
Any guess"s as to which of our favorite speaker manufactors B/W is currently supplying the Be product to ;)
Oldmics
TAD??
Rob:)
TAD uses the toxic version, JBL uses the non-toxic version.
In any case, there is no way to make a 476Be from any of the other JBL cores. We discussed it back in 2006 when it was relevent and it just won't happen. And hoping and wishing and dreaming won't make a difference. JBL would have been all over simply sticking a Be diaphragm into some older core to save costs if it would have done the trick. It didn't. Anyone who posts on a public Internet forum that they too can have 476Be performance simply by putting a Be diaphragm into an older JBL core is automatically discredited. These guys rightfully take their designs quite seriously and don't appreciate misinformation propogated by forum hacks.
That said, these Be diaphragms are a excellent option for other JBL cores. Plan on reworking any existing passive filters accordingly. Rather than wasting time comparing a 2451 (or any other core) against an "unobtainable" 476Be how about comparing a stock 2451 against a 2451 with a Be diaphragm. That would actually be relevent. Of course, no one can actually hear a driver or a diaphragm on a forum regardless of how many pretty graphs are posted.
I'm done with this irritating thread. :barf:
I believe Brush Wellman manufactures the Be material for virtually all of the audio market except for TAD who use vapor deposition (Yamaha used to use this method as well). There are also a few less reputable manufacturers who claim their Be dusted diaphragms are true Be... they are not.Quote:
Originally Posted by Oldmics
Toxic? All Be is toxic, but the sheet material that Brush Wellman manufactures isn't prone to shattering and releasing the toxic Be dust particles that can happen with a TAD diaphragm. Both types can be toxic, but when used properly neither is inherently dangerous, but if abused, the Brush Wellman material is significantly safer.
Widget
:yes:Quote:
Originally Posted by 4313B
:yes:Quote:
Originally Posted by 4313B
There are real benefits to using this material. It is pure physics not hi-fi hogwash. That said, as 4313B points out, the real proof is in the listening. With filter tweaks you can produce almost any plot... you can't make Ti sound like Be.
Widget
There was an embargo on Be material in some areas and this is most likely the reason why its use is not more wide spread.
Just reading this thread for the first time being in general audio discussion I am not sure why there is all the fess -up over this. I mean its not like JBL cares or has any actual control over what a diy blogger does or does not do in their spare time. Radian have been selling after market diaphragms for years, some Tad users quote they prefer them and that is their business. Some people prefer Acoustic Elegance drivers to Tad and that is their business.
But there is no free lunch and the more transparent the driver, the more flaws it will illuminate from the lesser quality mass market electronics. I recall Scotty discover this after trialing Bryston active crossovers.
(Last time I heard a Focal system using Be I was not that impressed.)
Therefore, unless you have the means to upgrade the entire signal path to that of the driver don't expect a miracle.
Well said, Ian Mackenzie; this also applies, especially in very low audio frequency transmissions & sub woofer speaker performance. It also severely impacts evaluation & comparison procedures of conventional wire against professional quality speaker cables and interconects. To begin with, conventional wire generates "phase shift-non linearity" & "phase shift-distortion", two distinct entities, which generate smearing of complex audio signals and increase of transmission delay time inversely proportional to the signal frequency. Phase Shift is related to Group Delay.Quote:
Originally Posted by Ian Mackenzie
Group delay in the audio field from Wikipedia, the free encyclopedia
Group delay is a measure of the transit time of a signal through a device under test (DUT), versus frequency. Group delay is a useful measure of phase distortion, and is calculated by differentiating the insertion phase...
en.wikipedia.org/wiki/Group_delay_and_phase_delay - Cached
Group delay is a useful measure of phase distortion, and is calculated by differentiating the insertion phase...Group delay has some importance in the audio field and especially in the sound reproduction field. Many components of an audio reproduction chain, notably loudspeakers and multiway loudspeakers crossover networks, introduce group delay in the audio signal. It is therefore important to know the threshold of audibility of group delay with respect to frequency, especially if the audio chain is supposed to provide a high fidelity reproduction. At the time of writing no extensive data is available, and the concept is often treated by "rule of thumb" or based on hunches and received wisdom. The best thresholds of audibility table below has been provided by Blauert and Laws:
FrequencyThreshold
500 Hz 3.2 ms
1 kHz 2 ms
2 kHz 1 ms
4 kHz 1.5 ms
8 kHz 2 ms
The table above has been published into the following article:
Blauert, J. and Laws, P "Group Delay Distortions in Electroacoustical Systems", Journal of the Acoustical Society of America, Volume 63, Number 5, pp. 1478–1483 (May 1978)
With professional cables correctly implemented, illumination of system components defects does facilitate the ability to locate & identify equiment system component defects to locate & identify problem areas for repair or upgrade, which were originally masked by conventional wire grunge.
New professional quality cables & interconnects requires a "break in" or "burn In" period of many hours & even days, which has to be repeated to a certain extent every time the cable is physically distrubed including disconnection & reconnection to the audio components. Bypassing this procedure renders cable comparisons "meaningless."
Bruce Brisson, Ceo of MIT Interface Technologies, has proven "If you can hear it but can't measure it, you are measuring the wrong thing." That is what you learn when you read his white papers and patents. See the "Skywalker 'Avatar" Movie applications credentials at this link:
http://www.mitcables.com/pdf/mit_movies.pdf.
At MIT Interface Technologies, you dont need to spend a fortune for 1st class professional speaker cables. Bruce Brisson will engineer your cable applications to match your specific system components. MIT cables are also are available for evaluation from the MIT lending library.
MIT Teflon cables, of performance identical to the $1000.00 Teflon Cables, are available under $100.00 with garanteed satisfaction or your money back.
Cheers, herki the cat
Holly Toledo (headquarters of Jeep) Robin.
I should have charged for that post!
I would suggest some disclosure and expansion of the hidden issues with some facts here. This thread is starting to read like a crap pocker game.Quote:
Originally Posted by 4313B
Firstly,
Motive: Guido is making a play (read marketing play or teaser) for what he sees as a potential market using the 0476 comparisons for Be after market diaphragms.
When I compare this type of smoke and shadows visibility stuff to some of the really excellent home grown cottage audio businesses in the USA that put in their own hard yards it makes me want to hammer down the protruding nail.
The JBL guys have the credibility as does 4313, always have had, always will.
Do JBL have pallets for shipping significant orders Ex Northridge?
This driver has many design features that were pioneered by the designer. Don wrote a good post on it once and it would be useful if it was re posted here.Quote:
In any case, there is no way to make a 476Be from any of the other JBL cores
Without making a rod for your own back I think that post was a little counter intuitive in that you have your work cut out for yourself re working all those network models for the aftermarket Be diaphragmsQuote:
That said, these Be diaphragms are a excellent option for other JBL cores. Plan on reworking any existing passive filters accordingly. Rather than wasting time comparing a 2451 (or any other core) against an "unobtainable" 476Be how about comparing a stock 2451 against a 2451 with a Be diaphragm. That would actually be relevent. Of course, no one can actually hear a driver or a diaphragm on a forum regardless of how many pretty graphs are posted.
Of course they won't be pure JBL drivers anymore.
Ian, You have stated a very gogent entiti: "Of course they won't be pure JBL drivers anymore."Quote:
Originally Posted by Ian Mackenzie
I had considered for a fleeting moment__equipping my 2440's pair with this Guido"Be 'Meme Brain", all to no avail. since, i do have new-in-the-box JBL 375 diaphragms. They won't JBL anymore, and what resale bail-out value would they ultimately have in the end?
My 2440's will improve immensely if I copper plate all the interior soft magnetic iron surfaces and the entire top plate, and while it is disasembled, i can convert these motors to "field coils" which will take me one step closer to the WECO 594-A Parent driver.
The orignal 594-A pair i had were stone cold flat to 7500 Hz and rolled off in a straight line at (6) Db per octave beyond 15,000 Hz which could be EQ-ued absolutely flat well beyond 15,000 Hz with a simple active RC pole in single ended WECO 91-B, 300-B Power Amplifiers, which was more than adequate to drive you out of the house. The 10,000 to 12,000 high frequency sound was absolutely Sweet, Using a pair of RCA Photophone Horns with of 150 Hz cut off, crossed over at 250 Hz on top of RCA Mi9462 Low Frequency Photophone Ubangi Radial Horns, I have never heard anythng better in my 72 years of playing with this stuff.
Cheers Herki the cat
There are people who make field coil compression drivers with Be diaphragms. Would be heavy and expensive!