My version of GM's 48" Jordan JX92S MLTL was discussed and pictured in the attached link. I shortened the length to 46" and added a ribbon tweeter in this design. But the basic MLTL is very nice with just the Jordan running full range. I have a DPDT switch and dual terminals in my design so I can choose between the Jordan JX92S full range with a notch filter or alternately go through the crossover and include the ribbon.
Jim
Jordan MLTL with a Ribbon
Jim
Jordan MLTL with a Ribbon
Jim,
I am interested in your approach of adding a supertweeter to the JX92s. Is the percieved improvement over the JX92s alone due to the wider dispersion of the ribbon tweeter or do you reckon it reproduces the treble more accurately.
Ted seems to be of the opinion that the differeing dispersion characteristics can ruin the holographic imaging of his speaker.
I must admit when I tried a silk dome tweeter in combination with the Jordan I was immediately impressed with the results but have now gome back to just using the Jodan alone - I feel that the placing of high pitched instruments such as triangles, cymbols etc is more accurate and although the treble does not sound so immediately airy and impressive, it does seem to be more varient - ie it is more representative of the true sound.
Still' I might be persuaded to try the ribbon. Does it have a wider dispersion than dome tweeters?
I am interested in your approach of adding a supertweeter to the JX92s. Is the percieved improvement over the JX92s alone due to the wider dispersion of the ribbon tweeter or do you reckon it reproduces the treble more accurately.
Ted seems to be of the opinion that the differeing dispersion characteristics can ruin the holographic imaging of his speaker.
I must admit when I tried a silk dome tweeter in combination with the Jordan I was immediately impressed with the results but have now gome back to just using the Jodan alone - I feel that the placing of high pitched instruments such as triangles, cymbols etc is more accurate and although the treble does not sound so immediately airy and impressive, it does seem to be more varient - ie it is more representative of the true sound.
Still' I might be persuaded to try the ribbon. Does it have a wider dispersion than dome tweeters?
Keladrin,
The small ribbon that I'm using provides a wider horizontal dispersion than a dome tweeter in the 3000 Hz and up region but especially in the upper octave--10-20 kHz. If you look at the horizontal dispersion of the JX92S alone you would notice that it narrows in the plus minus 45 degrees sector above 3000 Hz. Hence, you would notice the difference in dispersion even though the JX92S does have by design a rising on axis response. While the JX92S is acceptable in the upper couple of octaves, a good tweeter as you found out will be flatter and offer a wider horizontal dispersion than can the JX92S.
The tradeoff in this is the quality of the treble vs. the holographic nature of a single driver speaker. As 3000 Hz is generally considered the limit of the human vocal range, I find that a crossover to a good tweeter above that point will improve the sound.
Finally, the short ribbon that I'm using does have less vertical plane sound dispersion than the JX92S but at listening distances there is not an issue.
Jim
The small ribbon that I'm using provides a wider horizontal dispersion than a dome tweeter in the 3000 Hz and up region but especially in the upper octave--10-20 kHz. If you look at the horizontal dispersion of the JX92S alone you would notice that it narrows in the plus minus 45 degrees sector above 3000 Hz. Hence, you would notice the difference in dispersion even though the JX92S does have by design a rising on axis response. While the JX92S is acceptable in the upper couple of octaves, a good tweeter as you found out will be flatter and offer a wider horizontal dispersion than can the JX92S.
The tradeoff in this is the quality of the treble vs. the holographic nature of a single driver speaker. As 3000 Hz is generally considered the limit of the human vocal range, I find that a crossover to a good tweeter above that point will improve the sound.
Finally, the short ribbon that I'm using does have less vertical plane sound dispersion than the JX92S but at listening distances there is not an issue.
Jim
Another option may be to integrate the Jordan JXR6 with the the JX92. Although it won't have the dispersion characteristics of the ribbon, it does have the smoother HF whilst retaining much of the imaging of the JX92. At present I don't think Ted offers any crossover suggestions for this, which is a pity.
Jordan JX92S TL enclosures
Bruce. I built the above enclosures two months ago and while I think the bass is excellent, the upper range of women's voice is pretty harsh. Also upper registers of trumpet. The Australian distributor says "It is a characteristic of these speakers, regardless of their enclosure". Doesn't seem right to me as I have not heard of similar complaints. I am a fairly experienced woodworker but not speaker enclosure builder. Do you have any suggestions? Thanks Robert.
Bruce. I built the above enclosures two months ago and while I think the bass is excellent, the upper range of women's voice is pretty harsh. Also upper registers of trumpet. The Australian distributor says "It is a characteristic of these speakers, regardless of their enclosure". Doesn't seem right to me as I have not heard of similar complaints. I am a fairly experienced woodworker but not speaker enclosure builder. Do you have any suggestions? Thanks Robert.
Aside from providing a solid mounting point for the drivers, the cabinet doesn't do anything above it's operating BW, so harshness in the KHz regions is nothing to do with the box. So it won't be that. You might need some kind of notch-filter.
Harshness in female voice, more properly sibilance, is in the 5-8kHz band. If this is bothering you, you will need a notch filter as Scottmoose pointed out. While some pop singer are very spitty, operatic singers produce nothing at all in the band. Lowther and Fostex 206's are particularly susceptible to sibilance because they have a peak right at this band.
Bob
Bob
Re: Jordan JX92S TL enclosures
You don't say, but iif the Jordans aren't heavily toe'd in per the factory recommendation, then they will sound as you say. If its extreme HF sounds too rolled off for you and/or the 'sweet spot' is too narrow, then some form of EQ will be required and why I assume Jim Griffin opted for a ribbon tweeter to 'kill two birds with one stone' and what I would do if I should ever use these drivers.
GM
leeoh said:
You don't say, but iif the Jordans aren't heavily toe'd in per the factory recommendation, then they will sound as you say. If its extreme HF sounds too rolled off for you and/or the 'sweet spot' is too narrow, then some form of EQ will be required and why I assume Jim Griffin opted for a ribbon tweeter to 'kill two birds with one stone' and what I would do if I should ever use these drivers.
GM
Hi Robert,
Could it possibly be a little ripple you're hearing? Try adjusting the stuffing in the upper part of the cabinet by adding a little more and see what that does.
The Jordan driver has always sounded lush and wonderful to me. They make great sounding CDs sound even better and badly produced CDs sound horrendous. However, as GM mentioned above, don't listen to them directly on axis. Toe them in so they cross in front of your listening position so you're listening to them off-axis. It makes a difference.
I think all you need is a little tweaking to bring them around. Keep working with them, it's worth it.
Bruce
Leeoh ,Merry Christmas 😉
Jx92s can also sound harsh depending the source equipment .
Have you tried different amplifiers,for example?
Jx92s can also sound harsh depending the source equipment .
Have you tried different amplifiers,for example?
Jordan 92S TL
Thanks to abpea,GM,scottmoose and Bob Brines for your suggestions and comments. First, I must admit to mis-reading an email from the Australian supplier. He did not say that the problem is a characteristic of these speakers. Quite the reverse in fact. I have no excuse for that piece of stupidity except to say that maybe the questioning looks from my offspring are maybe sometimes warranted. The problem is certainly there, however and I will try the recommended toe in more thoroughly. Thanks also for the other suggestions which i will try later if needed.
Thanks to abpea,GM,scottmoose and Bob Brines for your suggestions and comments. First, I must admit to mis-reading an email from the Australian supplier. He did not say that the problem is a characteristic of these speakers. Quite the reverse in fact. I have no excuse for that piece of stupidity except to say that maybe the questioning looks from my offspring are maybe sometimes warranted. The problem is certainly there, however and I will try the recommended toe in more thoroughly. Thanks also for the other suggestions which i will try later if needed.
Jordan 92S TL
pikkujopo. Thanks for the suggetsion. I normally use a Cambridge 640A amp but have tried my old 15 year old Denon and the problem is still there. R.
pikkujopo. Thanks for the suggetsion. I normally use a Cambridge 640A amp but have tried my old 15 year old Denon and the problem is still there. R.
I've build a few years ago a TL enclosure based on the Konus Essence design but folded at 90° (the enclosure has a pentagonal section) and with an upper chamber with no parallel walls. They are almost not stuffed (just a little of dacron in the upper chamber + some car anti-rust blackson). Due to their shape they are wall mounted with the axis crossing one ft in front of the listener. Sound great with a cambridge amplifier. No baffle step correction needed, Subwoofer not required when playing mid to loud (but required when playing low).
Attachments
Thanks for your remarks following my post. I'm glad it was you and not me who put together a pentagonal cross section enclosure! A complex build. Can I ask you a question and so show my ignorance? How do you know if a baffle step correction is needed/ not needed? I have often seen reference to it but have not yet worked out the why of it. Leeoh
leeoh said:
To be honest baffle step correction mathematics is too complex for me. You can google about the explanations ( Baffle width/Wavelenght ). But you can also experiment it with any driver but putting them closer and closer to the wall: the wall becomes part of the baffle and you stop loosing low frequencies. In the case of the Jordan and the toe-in, putting the standard TL design against a wall is impossible.
Anyway this was an empiric thought, and I prepared the filter as proposed by Ted Jordan "in case of".
We did listen at the speakers with and without the correction circuit and they sounded much better without when fixed on the wall ( on a cambridge 540 - 80W / Channel - I play at -35db ). Sub isn't required at that volume (and from -40db) and when it's working it's only for frequencies that the Jordans can't handle properly anyway, even with correction (My sub is only for keeping the "easyness" of the speakers at very low frequencies, and is designed with few power but a high volume bass-reflex enclosure).
Sound very close to a live stage experience.
The best sound was not with the Cambridge but with a Mosquito (DIY class A), but the difference is very tiny (Cambridge is great for the money, especially for an AV amp).
Sorry for not being able to enter into real explanations. My way was purely based on experience and recomendations from friends with a greater technical knowledge than me! Even if folded at 90° to make a "L" and build with thicker 22 to 25mm MDF, internal size of TL and chamber are exactly the same as the ones of the Jordan design.
François
baffle step corection
Francois. Thanks for your reply. I have been mulling it over and have downloaded a baffle step correction circuit table put together by MJ King. Will see what I can do with some help from this end.
Francois. Thanks for your reply. I have been mulling it over and have downloaded a baffle step correction circuit table put together by MJ King. Will see what I can do with some help from this end.
Well, I've hovered and read as much as I can about GMs' 31" design and feel ( from the Comments ) that this is possibly the way to go for my first foray into the fullrange speaker experience.
I have two queries that I hope can be answered :-
My pair of jx92s has a sticky on the magnet sheild that reads 'Peerless 8ohm'. Is this rating correct - as I believe the units should be 6 ohm ?.
Secondly - I have been informed that 40" is the max height that the light of my life will tolerate. This means that the drive unit will be quite some way below 'ear height' when in situ. If I constructed the cabinets angled leaning slightly backwards, so that the drive unit beamed towards 'ear height' as well as as the recommended 30 degree toe in, would this cause anomalies in sound ?. The enclosure would be the same as per design with the exception that the baffle and rear although parallel would be inclined approx 10 degrees backwards. The top and bottom of the cabinet remaining horizontal.
I've tried most other designs of loudspeaker and apart from the old Quad esl57 have never found what I've been looking for soundwise. Unfortunately, two large radiators are not acceptable in our humble abode - so here goes with GMs' design.
Many thanks for your time in reading this, any opinions will of course be gratefully received.
John
I have two queries that I hope can be answered :-
My pair of jx92s has a sticky on the magnet sheild that reads 'Peerless 8ohm'. Is this rating correct - as I believe the units should be 6 ohm ?.
Secondly - I have been informed that 40" is the max height that the light of my life will tolerate. This means that the drive unit will be quite some way below 'ear height' when in situ. If I constructed the cabinets angled leaning slightly backwards, so that the drive unit beamed towards 'ear height' as well as as the recommended 30 degree toe in, would this cause anomalies in sound ?. The enclosure would be the same as per design with the exception that the baffle and rear although parallel would be inclined approx 10 degrees backwards. The top and bottom of the cabinet remaining horizontal.
I've tried most other designs of loudspeaker and apart from the old Quad esl57 have never found what I've been looking for soundwise. Unfortunately, two large radiators are not acceptable in our humble abode - so here goes with GMs' design.
Many thanks for your time in reading this, any opinions will of course be gratefully received.
John
JX92s + BSC and supertweeter
Hi,
A year ago I built the jX92s GM 31 MLTLs which I mixed with Jimmy Griffin specs in terms of baffle size and the addition the Aurum Cantus G2si with Mr Griffin Crossover (which rolls over at 3000 Htz).
While I was happy with the above, I felt that the life and soul of the jordans were somewhere hidden behind. I do not why this happened. Maybe it is because although I used reasonable good caps (clarity ps) I combined them with cheap inductors and resistors.
Anyway, after lots of trials I believe I have found what works best for my ears/my room and my system: I am running the Jordan's full range with the original BSC configuration suggested by Mr Griffin (1.5ml inductor and 4 ohms resistors) but I am running the 2GSi as super tweeters just above the Jordan's high frequency limit (ie 21500 Hertz) with a first order crossover using a cheap 1.23 Uf radio shack capacitors in parallel. The super tweeter idea wasn't mine, I took it from here: http://www.vanzylaudio.com/6_Steps_to_Faster_Sound.html .
This way I feel the Jordan's keep their main characteristics and coherence while the top and bottom get a nice kick that results in a very balanced system.
I just have question for those who know more:
Which type/brand of inductors and resistors would you recommend for the BSC and which type of of capacitors for the super tweeter xover. Are better components critical in this case?
Many thanks for your answers/comments.
Antonio
Hi,
A year ago I built the jX92s GM 31 MLTLs which I mixed with Jimmy Griffin specs in terms of baffle size and the addition the Aurum Cantus G2si with Mr Griffin Crossover (which rolls over at 3000 Htz).
While I was happy with the above, I felt that the life and soul of the jordans were somewhere hidden behind. I do not why this happened. Maybe it is because although I used reasonable good caps (clarity ps) I combined them with cheap inductors and resistors.
Anyway, after lots of trials I believe I have found what works best for my ears/my room and my system: I am running the Jordan's full range with the original BSC configuration suggested by Mr Griffin (1.5ml inductor and 4 ohms resistors) but I am running the 2GSi as super tweeters just above the Jordan's high frequency limit (ie 21500 Hertz) with a first order crossover using a cheap 1.23 Uf radio shack capacitors in parallel. The super tweeter idea wasn't mine, I took it from here: http://www.vanzylaudio.com/6_Steps_to_Faster_Sound.html .
This way I feel the Jordan's keep their main characteristics and coherence while the top and bottom get a nice kick that results in a very balanced system.
I just have question for those who know more:
Which type/brand of inductors and resistors would you recommend for the BSC and which type of of capacitors for the super tweeter xover. Are better components critical in this case?
Many thanks for your answers/comments.
Antonio
Last edited:
A while since this thread came to life.
I don't think the lower listening level will matter too much - the treble is listened to off-axis, remember, so as long as you're not much more than 15 degrees above driver height in your preferred listening position, it should be fine.
My 31 MLTL cabinets are 42" high - I haven't finished them yet but I doubt it will be a problem having the drivers slightly below ear level. My old 48" triangles had the driver at 30" high.
You could, of course, always fit adjustable feet under the cabinets and sneak them higher over time ... although it is amazing how quick the household authorities spot things like that. ("Is that black box new?")
I don't think the lower listening level will matter too much - the treble is listened to off-axis, remember, so as long as you're not much more than 15 degrees above driver height in your preferred listening position, it should be fine.
My 31 MLTL cabinets are 42" high - I haven't finished them yet but I doubt it will be a problem having the drivers slightly below ear level. My old 48" triangles had the driver at 30" high.
You could, of course, always fit adjustable feet under the cabinets and sneak them higher over time ... although it is amazing how quick the household authorities spot things like that. ("Is that black box new?")
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