Folke,
I regret that you are having problems. It is hard for me to troubleshoot from a distant location but I'll try.
The bass performance of the Jordan driver should be same with either of the two circuits. You are effectively driving the Jordan with the same value of inductor (1.5 mH) with the baffle step circuit or with the tweeter crossover circuit. Hence, the bass performance should be the same with either circuit.
I would suggest that you start with tracing the circuit to verify that you have correctly connected the components. Also confirm that the capacitor value is 6.8 uF.
If not resolved, the next step I would try is to would be to troubleshoot the woofer circuit by disconnecting the capacitor (one end would do). Now check whether the bass as you remember. What this will do is to effectively run the Jordan in parallel with the tweeter so the overall circuit impedance will be 4 ohms over the high end of the frequency band so listen primarily for just the bass response.
That should get you started. I'm concerned that the 6.8 uH capacitor is doing what it should do.
You can e-mail me if you need more help.
Jim
I regret that you are having problems. It is hard for me to troubleshoot from a distant location but I'll try.
The bass performance of the Jordan driver should be same with either of the two circuits. You are effectively driving the Jordan with the same value of inductor (1.5 mH) with the baffle step circuit or with the tweeter crossover circuit. Hence, the bass performance should be the same with either circuit.
I would suggest that you start with tracing the circuit to verify that you have correctly connected the components. Also confirm that the capacitor value is 6.8 uF.
If not resolved, the next step I would try is to would be to troubleshoot the woofer circuit by disconnecting the capacitor (one end would do). Now check whether the bass as you remember. What this will do is to effectively run the Jordan in parallel with the tweeter so the overall circuit impedance will be 4 ohms over the high end of the frequency band so listen primarily for just the bass response.
That should get you started. I'm concerned that the 6.8 uH capacitor is doing what it should do.
You can e-mail me if you need more help.
Jim
Hi Jim,
Thanks for the quick reply. I'll go through the setup of the cross over and try your recommendations. I'll even try replacing the 6.8uF cap with another type to see if this may be the problem.
Anyhow - I'll think I rebuild the cross over so I can A/B test the speaker with and without the cross over. This should improve my ability to assess the differences.
I'll post my findings when done, won't be until next week.
- Folke
Thanks for the quick reply. I'll go through the setup of the cross over and try your recommendations. I'll even try replacing the 6.8uF cap with another type to see if this may be the problem.
Anyhow - I'll think I rebuild the cross over so I can A/B test the speaker with and without the cross over. This should improve my ability to assess the differences.
I'll post my findings when done, won't be until next week.
- Folke
Samsagaz,
You can use the FR125 in a design of this type. It is a little less sensitivity than the Jordan JX92S.
The G2si ribbon (and most tweeters for that matter) will have higher sensitivity than almost any cone driver which covers the low end of the frequency band. What you do is to pad the tweeter down to match the sensitivity of the woofer. Happens all the time as inserting resistance in the tweeter path doesn't harm the box tuning of the woofer.
You have to also take care of the baffle step issue as well for most designs but that another story for now.
Jim
You can use the FR125 in a design of this type. It is a little less sensitivity than the Jordan JX92S.
The G2si ribbon (and most tweeters for that matter) will have higher sensitivity than almost any cone driver which covers the low end of the frequency band. What you do is to pad the tweeter down to match the sensitivity of the woofer. Happens all the time as inserting resistance in the tweeter path doesn't harm the box tuning of the woofer.
You have to also take care of the baffle step issue as well for most designs but that another story for now.
Jim
Question about JX-125 NG use in your design.
Dear Mr Jim,
Thank you very much for the careful design of these speakers, and your patient gentle reminders of the gestalt of the design to those who would bastardize it with their "improvements".
Having some of the most expensive equipment in the audio game, I marvel at how well my $50 fleamarket Nakamichi Stasis reciever matches up to $8000 Nestarovic Monoblocs. It really does come down to making compromises and just enjoying the music, not over tweaking it. So with that, your design is one that an imbecile like myself might actually be able to finish, so I have chosen it.
With all the chatter about your neat little design, I went to the EJ Jordan website, and found that they have a bargain price on the JX-125 NG, and suggest its use in your design will yield a benign improvement in bass down to 20Hz!, no small feat. I wondered what your thoughts were on this, as I read how carefully and thought out your compromises were. I would be interested if you can forsee any drawbacks, or if anyone has already built one of these versions. It sure would be nice to have more bass and save nearly $200 on the components. See the link here:
http://www.jordan-usa.com/specials.html
I'm sure you already thought of it, but here's my other probably uninformed question. What is your opinion on using an elliptical crossover network, which has very steep slopes, in this speaker. Such as the Infinite slope (patent Moddaferri ) from Joseph Audio. Their claim to fame is that metal cones make a lot of distortion at crossover points, and the infinite crossover narrows these bands dramatically. To the layman, this would seem to be a good match for the metal wooofer and tweeter in your design.
Here's the link to the infinite slope crossover clone.
http://ldsg.snippets.org/FILTERS/Cuadra/elliptic.php
Thanks again.
Dear Mr Jim,
Thank you very much for the careful design of these speakers, and your patient gentle reminders of the gestalt of the design to those who would bastardize it with their "improvements".
Having some of the most expensive equipment in the audio game, I marvel at how well my $50 fleamarket Nakamichi Stasis reciever matches up to $8000 Nestarovic Monoblocs. It really does come down to making compromises and just enjoying the music, not over tweaking it. So with that, your design is one that an imbecile like myself might actually be able to finish, so I have chosen it.
With all the chatter about your neat little design, I went to the EJ Jordan website, and found that they have a bargain price on the JX-125 NG, and suggest its use in your design will yield a benign improvement in bass down to 20Hz!, no small feat. I wondered what your thoughts were on this, as I read how carefully and thought out your compromises were. I would be interested if you can forsee any drawbacks, or if anyone has already built one of these versions. It sure would be nice to have more bass and save nearly $200 on the components. See the link here:
http://www.jordan-usa.com/specials.html
I'm sure you already thought of it, but here's my other probably uninformed question. What is your opinion on using an elliptical crossover network, which has very steep slopes, in this speaker. Such as the Infinite slope (patent Moddaferri ) from Joseph Audio. Their claim to fame is that metal cones make a lot of distortion at crossover points, and the infinite crossover narrows these bands dramatically. To the layman, this would seem to be a good match for the metal wooofer and tweeter in your design.
Here's the link to the infinite slope crossover clone.
http://ldsg.snippets.org/FILTERS/Cuadra/elliptic.php
Thanks again.
Jordan-USA is a licensed user of the MathCad worksheets. I know he was working on a few designs some months ago which I assume are some of the products he is offering. I do not know how to answer the rest of your concerns. I have dealt with Mark Dikovics at Jordan-USA for a few years and have enjoyed our correspondence and his enthusiasm for speaker design. He is making a serious effort to advance his design work with both simulations and measurements.
Serious? Apparently not since it sure looks like Jordan-USA is offering my strictly for DIY JX92S 48" MLTL, both stock and modified, save for rounding off fractions and changing the vent tuning for some driver I've never heard of. The fact that they at least gave you your due doesn't give them or anyone else the right to profit from mine or others intellectual property.
They say that plagiarism is the sincerest form of flattery and for some folks that's all the recompense they want/'need', but I got a lifetime (and then some) of it during my stay at corporate America, so pardon me for viewing Jordan-USA as just another greedy 'bottom feeder' trying to capitalize from the intellectual property of others.
GM
They say that plagiarism is the sincerest form of flattery and for some folks that's all the recompense they want/'need', but I got a lifetime (and then some) of it during my stay at corporate America, so pardon me for viewing Jordan-USA as just another greedy 'bottom feeder' trying to capitalize from the intellectual property of others.
GM
GM,
I understand your frustration, all I can say is that I cannot complain about what Jordan-USA is doing from my perspective. I know Jordan-USA has invested in my software and also testing software/hardware.
There are several other people on this forum posting plans for designs derived from my worksheets to facilitate the sale of their drivers and kits. I have not seen anything in return. Without the readily available designs the sale of their drivers would be greatly diminished. This is becoming very common and my own frustration and anger is building.
I have come to the conclusion that if you make something available for the DIY community, somebody will "borrow" your work and try to make a buck. So at some point you have to decide if you want to continue making your efforts available, I ask myself this question almost every week. At some point the, answer will be NO.
Right, and with the dirt cheap software available these days to design non-standard cab alignments anybody that can use a computer can fumble their way into making very good performing systems with nary a prototype.
My new design postings are few and far between these days and take pains to not include any knowledge not already posted, so already most of the way there. Unfortunately, with so much of our collective knowledge already published combined with enough of your software in play that in the scheme of things it no longer matters whether you, me, Scott, et al left the DIY forums forever.
As always, the few ruin it for the many.
GM
I've been down this 'road' before and the financially poorer for it with no satisfaction and no desire at this time to license my intellectual property to anyone for profit, so all I can do is voice my displeasure at every appropriate opportunity and not post any more potentially financially viable designs.
GM
Answers for Perfusionist's Questions
Your observations/questions:
1. "Thank you very much for the careful design of these speakers, and your patient gentle reminders of the gestalt of the design to those who would bastardize it with their "improvements"."
Yes, when a design is well developed, based on measured data, and well accepted by others it is necessary to throttle those who wish to make major substitutions and expect the same or better results. If one builds this design as defined, then they will achieve exceptional results. Otherwise you are dealing with your own baby.
2. Having some of the most expensive equipment in the audio game, I marvel at how well my $50 fleamarket Nakamichi Stasis reciever matches up to $8000 Nestarovic Monoblocs. It really does come down to making compromises and just enjoying the music, not over tweaking it. So with that, your design is one that an imbecile like myself might actually be able to finish, so I have chosen it."
You will be pleased with the results.
3. "With all the chatter about your neat little design, I went to the EJ Jordan website, and found that they have a bargain price on the JX-125 NG, and suggest its use in your design will yield a benign improvement in bass down to 20Hz!, no small feat. I wondered what your thoughts were on this, as I read how carefully and thought out your compromises were. I would be interested if you can forsee any drawbacks, or if anyone has already built one of these versions. It sure would be nice to have more bass and save nearly $200 on the components. See the link here:
http://www.jordan-usa.com/specials.html"
Well, the enclosure was developed for the Jordan JX92S driver and simulated with Martin King's excellent worksheet. I doubt that the JX125 driver would yield the same or better results without changes to the box. You can re-run Martin's MLTL worksheet if you wish but I doubt that you will get 20 Hz bass out of the JX125 in any enclosure.
4. "I'm sure you already thought of it, but here's my other probably uninformed question. What is your opinion on using an elliptical crossover network, which has very steep slopes, in this speaker. Such as the Infinite slope (patent Moddaferri ) from Joseph Audio. Their claim to fame is that metal cones make a lot of distortion at crossover points, and the infinite crossover narrows these bands dramatically. To the layman, this would seem to be a good match for the metal wooofer and tweeter in your design."
Many of the Joseph Audio designs use the Seas Excel magnesium cone woofers which have very large cone breakups (up to 20 dB or more peaks above baseline) in their out of band frequency response. Hence, it is necessary to pay special care in attenuating these peaks via high order filtering to pervent ringing of the response of the overall speaker. The infinite slope filters are one way to achieve an acceptable response with crossovers between these metallic woofers and any tweeter you wish.
In contrast, though an aluminum cone the Jordan JX92S is inherently wideband with very little cone breakup--either in or out of band. Hence, the Jordan drivers are much more adaptable to lower order crossovers and do not need infinite slope filtering. The choice of a ribbon tweeter in the case of my "Jordan with a Ribbon" design really dictates the crossover order as protection of the ribbon is needed for longevity of that transducer. The crossover in the "Jordan with a Ribbon" approach blends the wide bandwidth of the Jordan with the exceptional dispersion of the ribbon tweeter. You will be impressed. It is an excellent marriage.
Jim
Your observations/questions:
1. "Thank you very much for the careful design of these speakers, and your patient gentle reminders of the gestalt of the design to those who would bastardize it with their "improvements"."
Yes, when a design is well developed, based on measured data, and well accepted by others it is necessary to throttle those who wish to make major substitutions and expect the same or better results. If one builds this design as defined, then they will achieve exceptional results. Otherwise you are dealing with your own baby.
2. Having some of the most expensive equipment in the audio game, I marvel at how well my $50 fleamarket Nakamichi Stasis reciever matches up to $8000 Nestarovic Monoblocs. It really does come down to making compromises and just enjoying the music, not over tweaking it. So with that, your design is one that an imbecile like myself might actually be able to finish, so I have chosen it."
You will be pleased with the results.
3. "With all the chatter about your neat little design, I went to the EJ Jordan website, and found that they have a bargain price on the JX-125 NG, and suggest its use in your design will yield a benign improvement in bass down to 20Hz!, no small feat. I wondered what your thoughts were on this, as I read how carefully and thought out your compromises were. I would be interested if you can forsee any drawbacks, or if anyone has already built one of these versions. It sure would be nice to have more bass and save nearly $200 on the components. See the link here:
http://www.jordan-usa.com/specials.html"
Well, the enclosure was developed for the Jordan JX92S driver and simulated with Martin King's excellent worksheet. I doubt that the JX125 driver would yield the same or better results without changes to the box. You can re-run Martin's MLTL worksheet if you wish but I doubt that you will get 20 Hz bass out of the JX125 in any enclosure.
4. "I'm sure you already thought of it, but here's my other probably uninformed question. What is your opinion on using an elliptical crossover network, which has very steep slopes, in this speaker. Such as the Infinite slope (patent Moddaferri ) from Joseph Audio. Their claim to fame is that metal cones make a lot of distortion at crossover points, and the infinite crossover narrows these bands dramatically. To the layman, this would seem to be a good match for the metal wooofer and tweeter in your design."
Many of the Joseph Audio designs use the Seas Excel magnesium cone woofers which have very large cone breakups (up to 20 dB or more peaks above baseline) in their out of band frequency response. Hence, it is necessary to pay special care in attenuating these peaks via high order filtering to pervent ringing of the response of the overall speaker. The infinite slope filters are one way to achieve an acceptable response with crossovers between these metallic woofers and any tweeter you wish.
In contrast, though an aluminum cone the Jordan JX92S is inherently wideband with very little cone breakup--either in or out of band. Hence, the Jordan drivers are much more adaptable to lower order crossovers and do not need infinite slope filtering. The choice of a ribbon tweeter in the case of my "Jordan with a Ribbon" design really dictates the crossover order as protection of the ribbon is needed for longevity of that transducer. The crossover in the "Jordan with a Ribbon" approach blends the wide bandwidth of the Jordan with the exceptional dispersion of the ribbon tweeter. You will be impressed. It is an excellent marriage.
Jim
I have a question about the Jordans. I have
mine in a folded voight pipe, which is essentially
a folded BIB, whatever you want to call it.
There is some sort of mid-range suckout. The sound
is nice, but with a recessed midrange. Its not like its down
several db, but its down and I can tell. The bass is
strong but not overpowering, just about where I want
it to be.
Now, these cabinets were made for a bigger driver,
so what I did was to mount a small square piece of
mdf with a hole appropriate for the Jordans on the
main cabinets. The gap between the two pieces of
wood (the cabinet and the mdf square) has been
sealed.
The cabinets also have an exceptionally large square
section (like the BIB's open top) open at the other
end of the pipe. Could this be the reason of the mid-range
drop? I cannot figure out what's going on here.
mine in a folded voight pipe, which is essentially
a folded BIB, whatever you want to call it.
There is some sort of mid-range suckout. The sound
is nice, but with a recessed midrange. Its not like its down
several db, but its down and I can tell. The bass is
strong but not overpowering, just about where I want
it to be.
Now, these cabinets were made for a bigger driver,
so what I did was to mount a small square piece of
mdf with a hole appropriate for the Jordans on the
main cabinets. The gap between the two pieces of
wood (the cabinet and the mdf square) has been
sealed.
The cabinets also have an exceptionally large square
section (like the BIB's open top) open at the other
end of the pipe. Could this be the reason of the mid-range
drop? I cannot figure out what's going on here.
They were actually just a design out of an old elektor. I was very new then (i am new now 
). Anyway, they were not optimized for the drivers. The drivers were 8 inch audio nirvanas.
The dim are 35H x 14D x 8.5W... inner. Driver center is 150 mm from top (5.9"). I'd really like to keep these cabinets, made out of Birch ply. Also, I think the JX92s is a better match for these cabinets than the AN, which will eventually find its way on an OB. Eventually.....
). Anyway, they were not optimized for the drivers. The drivers were 8 inch audio nirvanas. The dim are 35H x 14D x 8.5W... inner. Driver center is 150 mm from top (5.9"). I'd really like to keep these cabinets, made out of Birch ply. Also, I think the JX92s is a better match for these cabinets than the AN, which will eventually find its way on an OB. Eventually.....
Combined Jordan with Ribbon and H-frame
Since this thread is active again, I decided to try to upload pictures of the combination I have been listening to for some time. This is the Jordan with Ribbon on top of the Goldmund H-Frame from MLK, using the passive crossover configuration. After much fiddling with placement and separation of units, it sounds very nice. In fact, after returning from RMAF last weekend, I am even more pleased with how well it sounds. The H-frames are sitting on Auralex Gammas, which helped, also, and I found the location of the Jordan/Ribbon to be critical with respect to the H-frame. That is the standard Parts Express enclosure for the top speakers. In this case, the Jordan makes a great midrange.
Since this thread is active again, I decided to try to upload pictures of the combination I have been listening to for some time. This is the Jordan with Ribbon on top of the Goldmund H-Frame from MLK, using the passive crossover configuration. After much fiddling with placement and separation of units, it sounds very nice. In fact, after returning from RMAF last weekend, I am even more pleased with how well it sounds. The H-frames are sitting on Auralex Gammas, which helped, also, and I found the location of the Jordan/Ribbon to be critical with respect to the H-frame. That is the standard Parts Express enclosure for the top speakers. In this case, the Jordan makes a great midrange.
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