Yet another Simple and enjoyable Jordan JX-92 Speaker

[stokessd]

At present, I am very happy with the MathCad program and the way the worksheets can be run for free by just about anybody. I am not really interested in putting the math into a different program but thanks for the offer anyway.

Thanks for the tips, I'll try it on my home machine (no norton).

But it's not really able to be run by anybody, only those running windows on intel. Granted, that's a majority, but I'm slowly working toward a windows free existance.

I'm in the middle of a speaker measurement software suite that I'm developing in labview. I've got T/S calculation, RLC calculation, and in-room sweeps. I'm currently working on MLS and gated time window. I'm planning to initially compile it for mac, windows, and unix on labview. If it really proves to be useful, I'll probably recode it to use Tk/Tcl for a nice cross-platform gui.

Sheldon

 

[MJK]

But it's not really able to be run by anybody, only those running windows on intel. Granted, that's a majority, but I'm slowly working toward a windows free existance.

Yes, the MAC users are not covered by the free MathCad software. But I am sure every MAC user has a friend who runs a Windows machine (I know they probably won't admit this but they really do like to argue the MAC point of view and need somebody to work on converting) so the option of running on somebody else's computer is available. If one really wanted to run the MathCad worksheets, I am sure a method can be found easily. For now things seem to be working out OK for most people who are interested.

 

[Doug]

JX92S

Doug/Brian

When I emailed Ted Jordan regarding this, I was informed that the voice coil inductance of the JX92S is 0.2mH.

Thank you John for going out of your way to e-mail Ted Jordan for the Le spec. I had looked for an e-mail address, but I couldn't find that either!! stupid, stupid!!




Doug

 

[BrianGT]

Re: JX92S

For those interested and don't have mathcad, I exported my Mathcad simulation using Martin's ml tqwt worksheet to html format, and posted it to my website:

http://brian.prohosting.com/jx92s/

It is updated with the Le parameter. I am seriously considering building this and trying it out.

The internal dimensions that I am going to make it are:
45" H x 6.5" W x [2.0" -> 10.5"] D

I am trying to get a copy of Visio, to make a drawing of how I am going to put it together.

If anyone finds any better optimizations to preform to get a better response, let me know. You should be able to replicate the results of my posting from the MJK's worksheets from http://www.quarter-wave.com

--
Brian

 

[BrianGT]

Here is a drawing of how I am going to put it together. I am going to make the front baffle double thickness, along with thicker top and bottom panels.

I couldn't figure out how to put dimensions (using SmartDraw), but they are the same as listed in the above post.

--
Brian

 

[Gaber]

Brian,

The electrical Q on your mathcad sheet is 0.441 versus the published 0.58, did you actually measure this value?

I too have been modelling this driver with the TL worksheets. I am looking at the tapered line design and have arrived at a volume of 24 L or so which seems somewhat large. I believe The Jordan website recommends a max volume of 12 L or so for a vented design.

The Vas is 15 for this driver and so I'm curious about the implications of going to a much larger volume.

Gabe

 

[dana]

Yes, the MAC users are not covered by the free MathCad software. But I am sure every MAC user has a friend who runs a Windows machine (I know they probably won't admit this but they really do like to argue the MAC point of view and need somebody to work on converting) so the option of running on somebody else's computer is available. If one really wanted to run the MathCad worksheets, I am sure a method can be found easily. For now things seem to be working out OK for most people who are interested.

I saw Martin's stuff was so excited that there was finally an analytical tool available that would supplement my calculator and photocopied tables, that I nearly "went Windows". But, I remembered back in the floppy archive, that I had an antique (in technology time) version of VirtualPC and wondered if it would work. So I installed it on my Macintosh, and it did.

The demo version of MathCAD runs well on it (is uses Windows 95), and while simulations are not really speedy and the files can't be printed or saved, Martin's tool set is, after-all, free. If you are like me, math-challenged, dangerous with a calculator or just plain unwilling to build 10 boxes to get one good one, getting friendly with a neighbor (since I am convinced that there is "one degree of separation" when it comes to people using Windows and the rest of humanity) is well worth the effort.😀

 

[stokessd]

Actually I'm as much or more of a Unix user than a mac or PeeCee user. I have a PeeCee for data acquisition and linux use. I have windows for certain uses, but I do most of my work elsewhere.

BTW, I got the mathcad worksheets working on my PeeCee. I uninstalled norton erlier this week and that may be why it works on my desktop machine but not on my work laptop.

I used mathcad in a college class about a decade ago, and I didn't like it much then, and I'd have to say my opinion is unchanged now. For high level math environments, I prefer matlab and IDL.

Sheldon

 

[BrianGT]

The electrical Q on your mathcad sheet is 0.441 versus the published 0.58, did you actually measure this value?

I too have been modelling this driver with the TL worksheets. I am looking at the tapered line design and have arrived at a volume of 24 L or so which seems somewhat large. I believe The Jordan website recommends a max volume of 12 L or so for a vented design.

Thanks for correcting me on the electrical Q value. I don't know where the .441 came from... I changed it and ran the sheets again. It makes a little bit of difference, but not enough to redesign.

I have decided to decrease the cabinet size a bit, with the bottom being 7.5" deep instead of 10.5" deep (4*Sd instead of 5.6*Sd). This gives a flatter response, but doesn't go quite as deep. I have updated my files at http://brian.prohosting.com/jx92s to reflect my changes. This lowers the displacement [xmax] a bit, and lowers the volume of the box by 24%

Here is a gif file of the comparison:

--
Brian

 

[Bricolo]

sweet 🙂

how much does one of those drivers cost?

 

[vpharris]

$105 US. But they're from England; wonder how much in France?

http://www.creativesound.ca/products.php?make=Jordan

 

[zeno]

You can order them directly from Jordan. Payment by credit card. Very correct and swift. And as a private person you pay VAT in England 17.5%.

http://www.ejjordan.co.uk/

They are around 195 pounds, VAT and shipping included. In Euro, max 300.

Marc

 

[planet10]

I wonder if dave is ever going to pass on the planns that use 2 of them drivers and a ribbon tweeter. ? HINT HINT.

If you decide to go this route, we can work thru it... there are quite a few possible variations

dave

 

[planet10]

Re: Re: Mathcad sheets

I have attached the ML-TQWT sheet that I am working on with the JX92S. My proposed cabinet size is: 46.5" H x 6.5 " D x [2" - 10.5"] W.

You have done a really good job of killing the ripple 🙂

An externally hosted image should be here but it was not working when we last tested it.

But what about the driver 23" off the floor? Are you going to put the pipes on stands?

Jason, we could use BrianGT's ML-TQWT as a basis. Can you live with a 46.5x6.5x8.25 inch cabinet?

dave

 

[planet10]

Actually I'm as much or more of a Unix user than a mac

But Macs these days are UNIX machines -- FreeBSD 4.x

dave

 

[Bricolo]

$105 US. But they're from England; wonder how much in France?

http://www.creativesound.ca/products.php?make=Jordan

twice my budget 🙁

 

[7V]

twice my budget 🙁

Yes, I can understand that Bricolo.

The thing is that Jordan (and Bandor) units are hand-made in relatively small quantities, to very high standards. It's inevitable that they work out more expensive than drive units which are stamped out by the thousand.

However, both Jordan and Bandor units offer the DIYer (or manufacturer) the chance to design without crossovers or with the crossover frequency well out of the sensitive mid-band and can thus provide years of listening pleasure.

I'd say they're more costly but excellent value for your money. If you want to work with these drivers, my recommendation would be to save up your pennies and wait a little longer. After all, the time and energy that most DIYers put into designing and building their masterpieces mean that they deserve the best. It's a shame to put so much effort in and then end up with a project that isn't as good.

The results can still exceed those of commercial speakers costing much, much more.

Steve

 

[planet10]

Jordan units are hand-made in relatively small quantities, to very high standards

Vifa is making Jordan's drivers for him now, so i am sure they are taking advantage of some automation.

dave

 

[Steve Eddy]

Vifa is making Jordan's drivers for him now, so i am sure they are taking advantage of some automation.

Ah, yeah. I remember Sead (Konus Audio) saying something about that a while back but it'd slipped my mind. A year or so ago he had me scoping out prospects here in the States. He'd been trying for a while to get Ted to get with someone that could produce them more uh... productively. 🙂

se

 

[BrianGT]

Re: Re: Re: Mathcad sheets

You have done a really good job of killing the ripple 🙂

An externally hosted image should be here but it was not working when we last tested it.

But what about the driver 23" off the floor? Are you going to put the pipes on stands?

I wanted to minimize the volume of the cabinets, while allowing easy building of the cabinets. I am going to use 2 sheets of 2'x4' mdf per cabinet, since I already have 4 laying around.

As for stands, I was just planning on putting them on a small stands. The driver will actually be 26.5" off the floor in my proposed cabinet. [cinderblock = cheap temp stand]

Another interesting idea that I was looking at last night was a tb w4-657s in a small tqwt/tl, along with a w3-871s on an open baffle. It looks like the w4-657s can go reasonably low, and work out in a TL. The price of drivers would be significantly less then the Jordans. Or if a larger budget was available, 2 of the w4 drivers in a tqwt/tl together, along with a ribbon tweeter, crossover around 5k could work out nice. I am going to on spring break next week, so I will see if I can get my girlfriend to drive, and I will play with mathcad in the car on the way there.

--
Brian