DD66000

[grumpy]

Cool. More inspiration re what to do with the set of 2234 and 2345s I have kicking around
:bouncy: Will be interesting to eventually hear more about the design elements and considerations
(in addition to what can be gleaned from the pictures and initial tidbits).

-grumpy

-Looks- like ~10ft3, deviated septum, flared dual ports, cc network, bi-amp-able,
custom port adapter/throat before cabinet integrated horn
and very little internal damping other than the ends of the long 1/2 cyl axis.

[Zilch]

I'm counting on Mr. Widget to come up with a horn. He has SOME experience with that. :p

Also, we'll need a little birdie horn for 2407/8 or BMS 4540.

For 4" diaphragm mid, the new 2452H-SL is a candidate, as well:

http://audioheritage.org/vbulletin/showthread.php?p=123766#post123766

[grumpy]

So cutting in at 700Hz makes vertical component alignment (the wider bandpass
bass driver with the horn(s)) less of an issue? or was this one area of
compromise (apparently not much of one, given the commentary so far), or
a "feature"?

-grumpy

[Hoerninger]

A comment regarding the 2441, 375 or any other JBL compression driver. The 476Be is better in every way! It measures better in response, harmonic distortion and decay properties - period. More importantly, it just plain sounds better by a huge margin, unless you like hash, grit and false dynamics due to diaphragm breakup. We will be glad to sell you one for a cool $3500. This has been an offer.

The white paper shows W x H x D:
965mm x 1092 mm x 464 mm
(38" x 43" x 18-1/4"),
slightly different than in the web.

The published CAD-drawings inspired me to take some measurements. There are certanly mistakes and it would be better to start with the real horns rsp. a real DD66000. But for a hardcore DIYer it might be a starting point.
____________
Peter (Posts: 100 :))

[Hoerninger]

... very rare. For your convenience.
____________
Peter

[northwood]

This has been an offer.

The white paper shows W x H x D:
965mm x 1092 mm x 464 mm
(38" x 43" x 18-1/4"),
slightly different than in the web.

The published CAD-drawings inspired me to take some measurements. There are certanly mistakes and it would be better to start with the real horns rsp. a real DD66000. But for a hardcore DIYer it might be a starting point.
____________
Peter (Posts: 100 :))

Wow,U r fast :bouncy:

[Hoerninger]

... from a korean site.
Any comments?
____________
Peter

[TimG]

I don't know how you will get an affordable horn built, but if you can find some way I'd like to try to build some. Maybe it would be easier to find an affordable way to cast some replicas of the TAD TH4003 horn.
I have a a pair of 2234H, some 2435HPL, and some 077's that I could try our for supertweeters. I have prototype woofer boxes that could be set up to approximate the woofer response. If someone can come up with a horn I could measure everything and come up with a 700Hz crossover for a system like this. I think the 2452H SL could potentially be a better candidate for the compression driver, but I certainly cannot afford $1315 for a single driver so I will have to wait until I can find some demos or refurbs on ebay for $225, the price that 2435HPL's have been selling for. The 2435H, to sound best, requires a crossover in the 9-13kHz range. I have been using them in some SRX horns and the clarity is amazing.

[speakerdave]

. . . . The 2435H, to sound best, requires a crossover in the 9-13kHz range. I have been using them in some SRX horns and the clarity is amazing.
You mean the 2381?

[TimG]

No, I'm referring to the 75x50 degree horn from the SRX715. http://www.jblpro.com/srx700/SRX700_Flash_Presentation/home.html

So what I want to know is how can the VRX915M, that uses a 15" neodymium woofer and the new 2452H compression driver sell for $1349 when JBLPro parts wants $1315 for the 2452H driver alone?

[Zilch]

So what I want to know is how can the VRX915M, that uses a 15" neodymium woofer and the new 2452H compression driver sell for $1349 when JBLPro parts wants $1315 for the 2452H driver alone?It ain't the "-SL," either. :dont-know

I don't know that slappin' an "SL" diaphragm into a 2452H gets you a 2452H-SL with a larger bolt pattern for certain, either.

In this price range, it's hard to say, "Worth a try...."

[Hoerninger]

... there seems to be a mistake:

Considering the fraction height to depth you get 1092 : 464 = 2,35. If you take the the distances from the drawing you get something like 2,5. By choosing the depth not beginning at the wooden corner but at the lips of the horn you achieve a better result, round about 2,4.

There is obviously a problem with accuracy, but the top view foto gives distances which correspond quite satisfying. There is always a problem with deformation if you take fotos. But the top view fits very well with a circle for example. I suppose the top view gives you an adequate (part of the) horizontal shape of the horn.
____________
Peter

[Guido]

Peter, are you already working at it? Where you live exactly?
You can have my 2441 with Beryllium Dia for testing.

[Hoerninger]

Moin Guido,

living in northern germany,
im wunderschönen Schleswig - Holstein.
PM follows during the day.
____________
Peter

[Steve Schell]

Although the DD66000 appears to use complex curves, it might be possible to build enclosuress that would come fairly close by using off the shelf formed plywood quarter or half cylinders. Anderson International Trading in Anaheim CA, for example, sells these parts in a wide variety of sizes.

http://www.aitwood.com/StoreFront.Asp?WoodType=POPLAR&CATID=10&Section=HALFCYL&wDesc=Half%20Cylinders%20(180%20degrees)

[Jan Daugaard]

I believe I have deciphered the curves of the DD66000. The formulae are as follows:

(434 / 488.5) * (488.5² - x²) ^ 0.5
for x = -482.5 to +482.5

691 - (691² - (x + 488.5)²)^0.5
for x = -482.5 to 0

691 - (691² - (x -488.5)²)^0.5
for x = 0 to 482.5

All measurements in millimeter. I have written an exposition in German of how I arrived at these results. Send me a PM with your e-mail address if you would like to have a copy of the exposition in PDF format.

[Guido]

You guys are awesome

[Hoerninger]

No comments.
____________
Peter

[grumpy]

Someone was recently asking about brands of non-polar electrolytic caps...
From pics, I thought I noticed Elytone's being used. Also have shown up in
pics of F30 Revel crossovers for sale on Ebay. FWIW :)

-grumpy

[Hoerninger]

... throat-horn transition for comparison.
____________
Peter

[Mr. Widget]

... throat-horn transition for comparison.
It is also similar to the H9800 as used in the K2-S9800 and Project May.

There are subtle changes in all of them however... a subtle change can be the difference between a decent speaker and a great one.

I am a little curious as to the purpose of these drawings and this discussion... are you guys going to make a speaker that looks similar to the DD66000, but isn't an actual clone? I can appreciate the beauty in the aesthetic design of the DD66000... but it seems that any attempt to visually copy it without a lot of detailed engineering data from the factory would likely end up with a pretty but perhaps unsatisfactory loudspeaker.


Widget

[Ian Mackenzie]

Maybe, Maybe not.

I agree a clone is often more difficult to get right so it does not have to be an exact clone.

The essential concept is sound and well proven.

Any design even a clone or otherwise takes fine tuning as I am sure that was the case with the Everest.

I have been pondering an opportunity for a 2 way with the virtues of this type of system for some time. The issue is the horn and a driver.

One of Steve Schell's drivers when they are ready could be quite something. Perhaps a Geddes wave guide or horn similar to what Jack as been using could also be interesting.

[Zilch]

I'm not seeing the correct exponential flare yet.

[They make you check yer roll of tracing paper at the door, I betcha.... ;) ]

[Hoerninger]

I am a little curious as to the purpose of these drawings and this discussion... Mr. Widget,

by the first drawing I intended to start a discussion for a more detailed view of the DD66000, although I have never seen before a speaker with so much information from the start. Based on public material I made a drawing which was never claimed to be correct. (The published CAD drawing will not become more exact by magnifying.)

There started no real discussion. I was was deeply astonished about the relation of numbers of readers to the numbers of contributions - up to 100 : 1. Saying "No comments." didn't mean that I was sort of proud, then I would have said "No comment." with a smile. I was bewildered about the lack of contributions.

The publishing of the last fotos has only been a provocation, although they were somewhat worthy for me because I have never seen a H9800. The provocation is due to the fact that a clone stays or falls with the knowledge about the horn. One dimension and some details are really missing.

I was much surprised about the Google ranking. Apparently not only forum members but any reader worldwide can look at these pictures, which I misjudged at first. It is not my will to help anybody selling an El Cheapo Clone. I'm off here, I presume.
____________
Peter

[Guido]

Someone was recently asking about brands of non-polar electrolytic caps...
From pics, I thought I noticed Elytone's being used. Also have shown up in
pics of F30 Revel crossovers for sale on Ebay. FWIW :) -grumpy

They use these damned elytones everywhere.
But I should shut up as Mr. Timbers himself corrected me with the hint the NPEs are there for a reason. Unfortunately without telling the reason. But I think I know it anyhow ;)

[Ian Mackenzie]

Hi Guido,

If I can just offer some input here (I will delete this in 12 hours)

Great thread by the way, keep it going!

There are major quality/parameter differences in parts. We've not talking a HAM radio set here. If I ordered std part by description from Mouser and put it in there it would explode! Yes that's right. They have to be high current types with high voltage ratings. These parts are not standard on the self items. They need to be rated like motor start capacitors or power factor correction as aside from the amp signal, there is also the back EMF from the woofer voice coil.

In certain instances some types of parts just work and other times not. Woofers also behave differently and are more sensitive to crossover parts/topologies than others.

For example the I bypassed a metalised foil 250 volt AXON 90 uf capacitor in my 3145 crossover with a 1 uf 600 Volt SA Clarity cap on my 4345 woofers and the difference was obvious. Shunting 100R resistance also improves things. Apparently North Creek makes a special capacitor that works well in this respect which I will try when it arrives. I did this mod on advise of an industry expert. There have been suggestions on the forum that below 300 hz NPE capacitors it does not matter. That maybe but it does above 300 hz, the woofer is still contributing above 500 hz in this system.You just have to hear it to figure that out.

I fail to see how an NPE would perform as well or better this instance but every case is different and I respect that.

Edit.

Well it would appear I am not entirely stupid. From the images below at least it obvious there is more going on than the simplified schematics suggest. Amen.

[Robh3606]

Just some clarification on the NPE use in the Everest and Ian comment below.


For example the I bypassed a metalised foil 250 volt AXON 90 uf capacitor in my 3145 crossover with a 1 uf 600 Volt SA Clarity cap on my 4345 woofers and the difference was obvious.


There have been suggestions on the forum that below 300 hz NPE capacitors it does not matter. That maybe but it does above 300 hz, the woofer is still contributing above 500 hz in this system.You just have to hear it to figure that out.


All of the NPE capacitors are bypassed with PP Solens as a minimum such as the 150Hz LF1 crossover point. Above that they are CC as well at the 800Hz LF2 crossover point. Judging from the size of the bypass caps they are not .01 Uf we would all expect. They look to be larger values so it appears they are running a ratio of NPE and PP where the NPE's are used. Heres one of Dons close-up's on a crossover I asked him to post. Can't get the values though:banghead: .

Rob:)

[grumpy]

I am a little curious as to the purpose of these drawings and this discussion...

I have been pondering an opportunity for a 2 way with the virtues of this type of system for some time. The issue is the horn and a driver.

I started this thread to stimulate discussion regarding what could be gleaned from the
current DD66000 design that might be of benefit to DIY-ers, whether clones (not my
personal intent) or otherwise. The available information has been both huge as well as
tantalizing in what was left out.

My parts collection has led to a prelim design something more akin to Guido's
Be-enhanced 4435's than the Everest 2's, but draws from elements of the newer JBL
design... heck, some of Bouska's info got boosted as well... gotta love this place. :)
Hearing more details about the "plan B" project May would certainly be welcome as well.

When I get some drawings together, I'll post and y'all can throw darts or shake your
heads and mutter :D

-grumpy

[speakerdave]

Beryllium diaphragms are pretty amazing, I think. They could be added to any JBL speaker with horn treble, 1" and 2" via TAD and 1.5" via TAD 4002 and JBL 2435. In some cases they might be plug and play substitutes and in others some filter tweaking may be necessary.

With regard to making the world's best components available to speaker nuts who are only semi-bonkers TAD has definitely out-classed JBL.

David

[Mr. Widget]

I started this thread to stimulate discussion regarding what could be gleaned from the current DD66000 design that might be of benefit to DIY-ers...That's cool... I just wondered what the direction was for the thread. As far as the DD66000 is concerned I see it as a highly evolved and specialized system... I am not sure what could be gleaned from it for a DIY project, but any source of inspiration is always a good thing.


Hearing more details about the "plan B" project May would certainly be welcome as well.No better time than the present. Start writing up some proposals... my understanding of the "plan B" was that it would be a DIY project using readily available parts and that people would pile on with their input. Anyone can start it. We were just discouraging the distraction while we were designing Project May. Get your creative juices flowing and make "Project Plan B" a reality.




Widget

[grumpy]

We were just discouraging the distraction while we were designing Project May. Get your creative juices flowing and make "Project Plan B" a reality.

Fair enough! :) I had the mis-impression that there had already been some
background conversation re plan-B .

Sounds like a good topic to pick up on a new thread.

-grumpy

[Guido]

Judging from the size of the bypass caps they are not .01 Uf we would all expect. They look to be larger values so it appears they are running a ratio of NPE and PP where the NPE's are used.
Rob:)

This is how I understood Greg Timbers. Not ONLY cost and size issues.

[Ian Mackenzie]

I thought the series coils in the sub driver were sledgehammer iron cores. The big coils might be for the mid bass driver. That means there is another board, perhaps there is an image somewhere.

[Hoerninger]

____________
Regards
Peter

[Ian Mackenzie]

Thanks.

It now makes a whole lot more sense, the NPE's in the sub are exclusive and is a Zobel. The others in the mid woofer are blended with Solens and biased from the parts count, they look to be about 1 uf.

Nicely layout and I love all that copper, money well spent there!

[Guido]

Personally I hate any kind of "Hype".
At the moment we have a B&W Hype here in Germany and probably whole Europe :barf:
My personal opinion is that the Everest is not only overpriced but also overrated. Problem is that to proove it I need to enter a damned plane to norway :banghead: or find the german distributor. I have a feeling who will be the importer here and it makes me sick. This company already imports the Array series and is known to be arrogant as hell.
Wrong guys chosen JBL-Management! Maybe that's why JBL don't sell well? I heard something similar from US forum members also. OK, I'll stop it not to start problems.

Back to topic:
I like the industrial design and the horn might be interesting with other driver combinations which is currently checked by some DIY maniacs.

That is the sense of this thread... IMHO :p

[Ian Mackenzie]

That reminds me of 3M and that is why they have competitors. They used to cry like babies when my clients specified the opposition in the tenders and contracts..tuff titties!

I can understand your feelings but we are here and this place exists because we are enthusiasts and I think JBL understands that.

In all my letters (dated back to 1980) from JBL they advise they unfortuately don't have the resources to assist individual diy projects but enthusiasts can obtain quite impressive results particularly if they use active crossovers.

Without the actual plans of the above design and fabrication resources it probably is a ball breaker to built is exactly as a clone. So use your imagination. I don't see the necessity to get hung up on all the hubba when you turn out a pretty nice job yourself with some of your own ideas. You only have to please yourself after all, just follow your ears.

Incidentally Visation in Germany have some interesting hardware:Here is a link to a local distributor. Precison Devices in the UK also make ans excellent range of Neo based drivers as to B & C. That hornnis getting some good press.
http://www.soundlabsgroup.com.au/pc/V-6056-M300/Visaton-High-End/Sound

[Guido]

You only have to please yourself after all, just follow your ears.


You are damned right Ian!
One day the sales structure will change and we can first HEAR and THEN BUY stock JBL.

Meanwhile we continue DIY :)

[Ian Mackenzie]

I heard the 704 today in a shop while looking at a Marantz SA/CD player.

For such a small system it was impressive, there was certain tonal quality to the midrange that makes you wonder. I imagine the 800 series would be another story again..an then there is the technology!

Ian

[grumpy]

~9ft dia (horn rotation) ... haven't estimated vert profile.
39-40" dia cab
5 pt cubic spline fits hor. mouth profile nicely.

[Zilch]

~9ft dia (horn rotation) ... haven't estimated vert profile.
39-40" dia cab
5 pt cubic spline fits hor. mouth profile nicely.Uhmmm, 39.37" maybe? ;)

I have no clue what a cubic spline is, but it certainly looks right. :thmbsup:

[Mr. Widget]

I have no clue what a cubic spline is, but it certainly looks right. :thmbsup:It's a bezier curve. A curve that is not based on simple radii, but uses a complex mathematical formula to derive it... any accelerated curve, like say a "french curve" can be represented with bezier curves.


Widget

[Zilch]

It's a bezier curve. A curve that is not based on simple radii, but uses a complex mathematical formula to derive it....All-RIGHTY, then, we know what to punch in, now.... ;)

[grumpy]

yup. my point was the top-down view of the horn expansion does not appear to be a
simple curve. One -might- assume (or not) that the internal horn throat follows a similar
expansion.

? Sure 39.37" if that floats your boat :) ...given the limited photo resolution, scaling,
steadiness of my hand etc... and the fact that I don't think it matters all that much.
Did I miss that spec in the docs too? :o:

-grumpy

[Mr. Widget]

Did I miss that spec in the docs too? :o: That's the inch equivalent for 1 meter... it would be a likely guess.

I can give you the actual curve of the H9800... I believe that the initial curvature is the same. Send me a PM with contact info and file type requirements... here is the H9800 from my CAD data.


Widget