Which high-xo tweeter to use with a Jordan JX92S?

[soongsc]

The Jordan sound ok by itself, I have played over 2 months in a 30cm MLTL, but I must admit I didn't tweak it that much other than using a deq2496 to eq the responds but still couldn't get it sound right.
I think part of the fault is due to my box design but I couldn't what was the problem.
So I went back to my 2-way scanspeak and it was good.
I put in a Morel MDT40 tweeter with the Jordan and I like that better. I think the respond breakup at 8k above can really be heard and therefore the improvement with the tweeter.

I kind of get the impression that MLTLs need to be long to cause the long side to resonate at the right frequency. Did you use the MJK worksheets to do the design?

 

[ChuckT]

Sorry, my mistake, I think that should be 30+ inch instead of cm. It is 81cm line to be exact. I have attached the design.

I have use Martin King mathcad sim for the design, it is not a straight line, the ripple is less if not straight.

The Jordan is ok, but when compare to the near top-of-line scanspeak driver (9700+8530) and a cap-less crossover. Well, all I can say is I like the scans better.

 

[soongsc]

Sorry, my mistake, I think that should be 30+ inch instead of cm. It is 81cm line to be exact. I have attached the design.

I have use Martin King mathcad sim for the design, it is not a straight line, the ripple is less if not straight.

The Jordan is ok, but when compare to the near top-of-line scanspeak driver (9700+8530) and a cap-less crossover. Well, all I can say is I like the scans better.

I do recall I have a pair of the early D2905 models somewhere, the hard dome type. A two way system as such does have advantages, especially listening at loud levels. This depends an room size as well. The Jordans perform well from very low levels (one notch up on the systems I use) to normal concert hall 10th row and more listening levels.

With the JX92S design you show here, did you add any compensation circuit? Did you do a baffle step simulation?

 

[ChuckT]

No BSC used, I use a Behringer deq2496 so basically I can produce a very nice responds curve. But I must addmit I haven't give the jx92s enough time to fully reach its potential. Also, I have a feeling the MLTL by GM will be a better box than the one I have (which uses plywood btw)

I see the deq2496 is around $250 in the US, so I strongly recommend this gear.

Did I mention I put a layer of damar on the Jordan?
No!
Well it smooth out the top a bit.

 

[soongsc]

I've heard that the deq2496 is programable, is that so?
What's damar?

 

[ChuckT]

My bad, that should be dammar. It is a type of resin use in painting, you can get it in art shop. Do a search here and you'll find some info on it, people sometimes apply it over speaker cone as a tweak.

Again, do a search on deq2496 and you'll get lots of info.

Here is a review on an older model.

http://www.enjoythemusic.com/magazine/equipment/0101/behringer8024.htm

 

[soongsc]

I think I got a few models mixed up. I think if you try using the EQ to adjust it so that starting from 1K Hz, increase each band a little higher than the higher band such that you have half a smiling mouth down to 6db at 40Hz, then flat out, and listen. Then raise starting around 5K, gradually raise the gain until you reach about 1db at 20K. Then see how it sounds.

Dammar will add weight to the cone. Jordan cones are anodized to a specific thickness to maintain certain properties. Adding a coating really defeats the original design objective. Although dammar might add more damping to the cone, but the stiffness properties have changed. Really don't know what the tradeoff is by doing this.

 

[ChuckT]

The Jordan is out of the system now, let's just say I am still a bit relutant to put it back in.

I know about the dampening, that is the whole idea. And I think it reduce the cone breakup a bit, or at least the brightness.

I know a company who have glue thin gold foil on the jx92s cone and sell it at a much marked up price. Don't know if it is real gold however.
Crazy. Maybe that is why they are no longer carrying the Jordan.
Interesting, it is the same company who brings you the LCY ribbon tweeter.

 

[soongsc]

Thought you had more than one system.

 

[ChuckT]

You can too, if read some of the thread here. Just diy. A Glainclone here and a T-amp there, and get some cheap quailty dac from diyzone Taiwan and those tasty OCC copper/silver wires also, and Fostex 103 and ...
Well you get the idea. I haven't brought anything from diyzone actually, but they have some pretty good stuff.
Oh, as a source, I use a cheap Toshiba 3950 and a TVIX music module. Do a search and you'll find some info.

 

[Dumbass]

Varnish on a JX92S?

Besides being specifically recommended against by the man himself (http://www.ejjordan.co.uk/faq.html#faq10) it seems to run contrary to the raison d'etre of the driver, namely stiffness and lightness.

AFAIK varnish is used to increase the stiffness of paper cones, I can't see it having the same effect on a metal foil cone.

ChuckT, if you ever want to get rid of those Jordans, get in touch and maybe we can work something out. (Provided you didn't dope the surrounds as well as the cones.)

(EDIT: although shipping from HK to the States probably would ruin the economics of it . . . .)

 

[ChuckT]

I wanted to use the C37 stuff, but they are far too expensive.
I think the jx92s can sacrifice a bit of speed to smooth out the top.
That's is what they say about the much more expensive Lowther, but people do it anyways (dammar on cone).

Thanks. The shipping will not made it worth while.
I'll keep it for a while, for the cost of the speaker, it kills a lot of commerical speaker out there.

 

[soongsc]

I'm closer. If the cones are still smooth and nothing else doped. Let me know if you want to get rid of them.

 

[ChuckT]

Just the cone is doped, of cause.

I am pretty sure you can built one at cheaper cost using GM's MLTL design.
The box is too big and heavy for shipping.

 

[soongsc]

I have my own enclosure design.

 

[navin]

ok jordan experts,

my is to use a set of 5 jordans on wall boxes (about 8 liters) sort of like B&W VM1.

They will be used for HT/AV and music (60-80 rock, some classical and some jazz) powered by a Marantz SR7000 HT/Av reciever.

What do you think? does it make a sound investment (we have to import and pay significant duties on these in India)?

There will be a 2 subs in the room so the Jordan's will not have to perfrom those duties.

How low can i cross the Jordans?

 

[soongsc]

Navin,

How big is the room the system will be in?

I would assume in India, there might be some tax differences between parts and finished products. Normally part will have less duties.

 

[navin]

the room is L shaped about 450 sq. ft with a 9 ft ceiling.

 

[soongsc]

This room size is just around the limit. I think if you like heavy bass with punch, if it's just two channels, then it might be on the lean side with Jorans alone. But would be great for most Jazz. With the two subs, it's kind of hard to tell. I would work with the Jordans first, and bring the Subs in where the Jordans start rolling off.

Perhaps Collin can provide some input, since he has a setup. My JX92S surrounds are still on paper, and the drivers are still in the box.

 

[Dumbass]

This room size is just around the limit. I think if you like heavy bass with punch, if it's just two channels, then it might be on the lean side with Jorans alone. But would be great for most Jazz. With the two subs, it's kind of hard to tell. I would work with the Jordans first, and bring the Subs in where the Jordans start rolling off.

Perhaps Collin can provide some input, since he has a setup. My JX92S surrounds are still on paper, and the drivers are still in the box.

Just for background: I've heard Jordans in VTLs, I really liked the mids and highs, thought they were great. Bass was shy, but it was a super-dead room.

I've been toying with the idea of putting Jordans in sealed enclosures, letting them roll off naturally, augmenting with stereo subs.

But as long as you have woofers in stereo, why not cross them higher, like 250Hz or so? This involves using an active filter on both the Jordans and the woofers, but so what? The idea is, let the woofers carry more of those bass freqs, perhaps a little more "oomph" in those kick drum freqs, but still cross below the "crucial freqs".

Just woolgathering . . . .