JBL 4675C with TAD 4002 compression driver

1. yes.
2. if you can't find the tunings, try contacting jbl pro tech suppport.
http://www.jblproservice.com/support_info.htm
3. the 2226h is a high power driver that likes high power.
1000-2000 watts per pair would be in the ballpark.
the cd's in the horns will likely only ever see a few watts even when you cringe from how loud they are.

oh, minimum, a decent receiver would be fine 50-100 watts.

Wow, I bet this turns out to be a hell of a speaker! That TAD driver is freaking awesome! I wish that I could afford to put those TAD drivers in the Corn-Scala's that I will be building this winter! Keep us updated as to how this turns out!

TADs are sweet, you can get subjectively close fo a helluva lot less but yep, they are nice.

IIRC, Penn had some and experimented w/them. Entirely different, however I used to cover small live venues with a stout, JBL/TAD combo. Each side had (4)15s and a 12" two-way top with those sweet TADs on the HF.....un-solicited compliments every single event. I absolutely loved that rig. You get much bigger, ...with multiple MF/HF sources, things begin getting messy. That's the sweet spot-a single top per side (w/ample LF of course).


Best of luck, and congrats on the gear. I'm glad you posted in here, ...this crowd in here with take care of you

I am curious as to which drivers you would recommend for getting "subjectively close for a helluva lot less" than the TAD?

MBGR199-

That will be a nice setup. Given the amount of money you have in your system I would highly recommend measuring your speakers output and setting the DBX based on those measurements. It will only cost you a few hundred dollars. The group here can help you figure out how to do that. A good option would be the OmniMic setup from Parts Express. You will measure the horn and then the woofer. We can then simulate your response and help you with your DBX settings.

Getting your response right with the DBX and measurements is vital.

As far as power needed. It depends on your listening levels. You can use a pretty low power amps with the 2226 but more is better.

Take a 4" diaphragm JBL driver like the 2452H or a Radian 951 or 952 and put a Truextent beryllium diaphragm in it. It will cost around $1000-1500 depending on how much you pay for the CD. The be diaphragms are something like $600 IIRC.

Max beat me to this. You can get 2450SL's right now on e-bay for $500 (which is no slouch). Add the $600 truex phragm and you have bascially a 476be. I think those are over $2.5k if you can even find them.
You could also use a 2447 for less money, but I think the back cap is different. I'll let you know next year...I've got the 2450-sl's.

most folks don't know what that means...

a berrylium compression driver is pretty much the pinnacle of compression driver technology. it is what jbl uses in their cost no object everest/k2 lineup:



they are definitely a rare item, like wrager says. i don't think you can even order them from jbl...

same thing with those woofs...1500al...loaded with technology...again i don't think they can be ordered from jbl. the last that i checked, $1500 from japan ea was what folks were doing.

If someone where to go with a JBL 2452H compression driver matted with a Truextent beryllium diaphragm, or a Radian 951/952 compression driver also matted with a Truextent beryllium diaphragm, what would be a good horn to go with these? Also, since these would serve as my mids in a 3 way system, what tweeter/horn combo would be able to keep up with those really good mids?

H9800 or even a 2352 seem to work pretty well according to the LH site. I use 2384's because I have an AT screen.

http://www.avsforum.com/t/1225270/the-semi-clone-of-jbl-3731s-build-thread/1020

It's a long read, but well worth it. Sadly, Zilch, one of the foremost JBL authorities, passed last year.
Edited by Wrager - 11/4/12 at 7:48am

Yeah, beryllium compression drivers are the choice of many of the best designs. Great care must be taken when handling the material, serious business. As most everyone likely knows, it's strength to weight ratio is ideal for MF/HF drivers.

JBL beryllium based offerings are nice, but no guarantee to good sound. At Cedia this year, Harman put on quite an ambitious demo (for Cedia standards) in the adjacent Westin hotel. They used a sizable, high ceiling meeting room. In system put together, set-up and personally supervised by Kevin Voecks, and fully utilized all the software goodness Harman has (maybe that's the problem). Anyway, the point is this was the most lame, underwhelming state of the art demo I'd ever heard. I took notes if anyone's interested.

Yep, beryllium compression drives up front. JBL's Atlas, LCRs, which have beryllium MF and HF drives each. All optimized and powered by mega-buck Mark Levinson amplifiers. I sat front row, center, right where the guy who balanced the system (Todd Packer) told me to sit. They proudly proclaimed a $270k figure on just the audio system.

lt it was decent, however nothing more. Front row center, I was looking forward to enjoying the clarity and capability of a fine beryllium front stage.

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mbgr199,

Good luck with your gear. Keep us posted.

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Martycool

I don't have specifics, merely saying one can do well with less. I'm anything but an expert on the individual choices, but I have heard a lot of pro cabs and the best are sweet, but like many things, there's a sweet spot in pricing below the best.


Thanks

"Anyway, the point is this was the most lame, underwhelming state of the art demo I'd ever heard. I took notes if anyone's interested."

well $270k is ridiculous, but other than that, what didn't you like?

I am running the Truextent beryllium diaphragms in JBL 2446 CDs, mated to IWATA 300 horns.

I've never heard anything better!

http://www.diysoundgroup.com/iwata300.html


_____________
Best Regards,
Carl Huff

Why do Beryllium diaphragms sound so much better? Looks like I could get one to put in my JBL 2445's but would it sound $600 better than the titanium one's or would it be a better idea to just get another CD?

I was cynical and was slow to buy them but am now glad that I did. The measured frequency response of the beryllium diaphragms is very similar to the aluminum diaphragms that I replaced. What I do know is that the diaphragm breakup modes have now shifted up and out of the audible band. If that is what I am hearing, what a difference that makes!
______________
Best Regards,
Carl Huff

Read TruExtent's whitepaper. They explain the advantages of Be over Al and Ti. It is tough to beat. Is it worth the money, that is hard to say. I can say this, I would rather go from 4 woofers per LCR to 2 woofers and upgrade from Ti to Be. I know you got the 2226's for less than retail but it is still a trade off I would take any day. If you want them I know a distributor that can give a fair price (not me...not shilling).

Papers:
http://materion.com/~/media/Files/PDFs/Electrofusion/TTB002_TuningForks.pdf
http://materion.com/~/media/Files/PDFs/Electrofusion/TTB001_SSX_Vs_Radian.pdf

From what I understand, these are an improvement over the JBL and TAD diaphragms. I've heard that 18Sound is using them in their new uber driver.

I read all those right after I posted. Still not sure if that is more marketing than real science. But I'm sure these are a real upgrade but how much so? I guess I'd have to compare. Lol and no, I won't downsize the woofer section but I will put these high-end diaphragms on my upgrade list. The waterfall on that Radian Vs pdf definitely shows the goods. I'll have to remember to hit you up when I can afford these guys.
Edited by Scott Simonian - 11/7/12 at 11:06am

Scott,

You live quite close to me. I invite you to come down and have a listen.
_____________
Best Regards,
Carl Huff

Scott, there is really no way to quantify the difference. You should go listen to Carl's system. You are really committed to having huge woofer headroom, huh?

Interesting,...wondering, is this the drive unit PNW employed in the PS compression waveguides?

btw, coctostan, those were fascinating discussions you all had wrt his addressing of various acoustic distortions, I wish I could've added somethin of substance but was way outta my wheelhouse.

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Carl, those look wonderful, just simple and well executed. Thanks fo sharing the pics. Scott I'd be all over that, just sayin'. Report back. Yhis is an aspect of this hobby that in my opinion is terribly lacking; ie, visiting like minded others, talking audio. One gains a well needed dose of perspective (at least I did). A few months ago, I traveled out of state to hear BWaslo's diy Synergys. Wow,.... quite the ear opening experience in what's attainable for an incredibly small amount of money. I mean I'd just taken delivery of quite an expensive Seaton Cat, and multiple SubM system. Then I hear how these dirt cheap drivers sound he's put together in a Danley Synergy based floorstander, and I couldn't believe how these modest drivers could amount to what I heard.

$45 compression HF drivers, combined with (4)$2 mids, and (4)$9 woofers!

A recent post I read illustrated all parts for a triple, LCR set, was $419!

Anyway, a trip visiting another forum member showed me a perfect example of what's attainable with a well executed (very ingenius Danley) design, with the most modest drivers you can imagine.

Here's a quote from BWaslo;
"Tom's synergy concept really does make it all sound like one driver. Not like a driver, even, more like an emission from the air in that region. The SEOS15 had a slightly different sound between the woofer and waveguide, not at all bad, but not like one driver. Some of that effect is likely psychological, it is odd with a synergy that everywhere the sound character is the same no matter how close you are to them. ..... Very easy to listen to, no mental confusion at all from split up sound sources."

I concur, wide, wide sweet spot, very natural easy presentation. Most importanly, superb conversation. I'm sure Carl would be equally as engaging

I missed a good opportunity to talk shop with him at a Cedia demo a year ago. Man, I'd love to hear those IWATA horns mated to those sweet compression drives. I've read his posts mentioning other speakers he's heard,... saying these two ways are the best, possesses some considerable weight.


Thanks

FOH-

I'm referring to the ND4015Be. It looks like it is made to replace JBL 1.5" large format drivers. http://www.eighteensound.com/index.aspx?mainMenu=view_product_simple&pid=321

You will notice it uses a polymer surround Be diaphragm. The only Be diaphragm that I know of that uses this tech is Truextent. It is my understanding that by using a polymer surround these are more durable than the JBL and TAD phragms.

The Synergy design is IMO the most revolutionary design in loudspeakers since the horn itself.

"The Synergy design is IMO the most revolutionary design in loudspeakers since the horn itself."

I agree. Tom Danley recently told me in an email exchange that the Yorkville Unity loudspeaker can be brought to current Danley horn status simply by improving the crossover. For a while I toyed with the idea of doing that as a published forum project.
____________
Best Regards,
Carl Huff

"I am running the Truextent beryllium diaphragms in JBL 2446 CDs, mated to IWATA 300 horns.
I've never heard anything better!
http://www.diysoundgroup.com/iwata300.html"

that looks serious old school carl...almost like a very high tech version of something jim lansing would have been working with in the 1940's. i used to think such designs looked retarded...until i began to understand their performance. just need to drop a little coin in there in order to spruce up the looks of the system and you would be in "price is no object" territory.

"I agree. Tom Danley recently told me in an email exchange that the Yorkville Unity loudspeaker can be brought to current Danley horn status simply by improving the crossover. For a while I toyed with the idea of doing that as a published forum project."

interesting. i know that he helped cowan get his diy unity crossover dialed in. i can definitely see folks interested in something like that.

Thanks for the heads up, as I wasn't fully aware of the individual distinctions.

I do enjoy reading even the most ambitious diy projects and, but my involvement doesn't extend much past that

In my search for new mains, I experimented with and considered many options, including a 60x90 Synergy model. In the end, Seaton's Catalyst design won me over for my current room. Upon completion of this primary family system, I may pursue a very ambitious diy Synergy type approach in a ground up, purpose built HT room. What I heard while listening to the home brew Synergy designs, with the most modest of drivers, has since inspired me to keep such an approach foremost in mind.

In my mind, I see an entire room/system approach as one. Minimizing cabinet contributions, and acoustic distortions like SBIR and diffraction, via employing the entire left-front-right boundary surfaces as an integral part of the design. I'm picturing some Synergy type thing embedded into the L&R surface corners, and some yet to be determined center utilizing a similar technique.

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Regarding the Yorkville Unity, I'd think more enthusiasts would experiment and dabble with these. I wish my local Pro Audio shops carried them, so I could rent them and see what they're made of.

Also, fwiw, there's more than just Yorkville and Danley using his designs. I've seen several pro offerings with such. Even nice small products (ie, double 8" two ways) , merging these techniques with narrow verticals and line array-ability. These may not follow every element, but I've seen them around.


Thanks

FOH-

Nothing wrong with Seaton Cats. I've said it many times, but a well-designed speaker is the more important part.

Funny, I'm actually exploring something similar to what you are talking about. A bit of a take on PNW's Octagon with Synergy's. I'll let you know when I get it done and you can come over to check it out. It is always good to have an experienced set of ears double check a design.

Please Carl, pretty please!