Jordan JXR6HD in german DIY magazine Klang&Ton
Hi,
the german DIY magazine has published an implementation of the Jordan JXR6HD in a two way box in D'Appolito arrangement using two Visaton 5" aluminium drivers as bass department crossed over at 500 Hz. You can see it here:
http://www.lautsprechershop.de/hifi/index.htm?/hifi/minium.htm
I have not heard this box up to now, but looks quite promising...
Best regards, Stefan
Hi,
the german DIY magazine has published an implementation of the Jordan JXR6HD in a two way box in D'Appolito arrangement using two Visaton 5" aluminium drivers as bass department crossed over at 500 Hz. You can see it here:
http://www.lautsprechershop.de/hifi/index.htm?/hifi/minium.htm
I have not heard this box up to now, but looks quite promising...
Best regards, Stefan
english version available
Hi,
here is the link to the english version:
http://www.lautsprechershop.de/english/index_hifi.htm?/hifi/minium_en.htm
best, LC
Hi,
here is the link to the english version:
http://www.lautsprechershop.de/english/index_hifi.htm?/hifi/minium_en.htm
best, LC
I would be more interested in how the little Jordan performs solo in hm`s double horn.
http://www.hm-moreart.de/105.htm
http://www.hm-moreart.de/105.htm
This is the second time now I've seen someone describe the JXR 6 as having less depth. (..Colin were you the other person?)
I've described already why it would have more width..
but why not more depth?
I think its likely to do with the interaction of the frame and surrounding area (compression and airflow resistance). A good wave guide starting "in front" of the magnet and effectivly wraping around the frame spokes should do the trick.
I've described already why it would have more width..
but why not more depth?
I think its likely to do with the interaction of the frame and surrounding area (compression and airflow resistance). A good wave guide starting "in front" of the magnet and effectivly wraping around the frame spokes should do the trick.
"Due to the small size the Jordan JXR 6 HD is not capable of producing low bass at an adequate level[.]"Colin said:
BTW I think that having a published design, with widely available drivers and easily built passive xover (and now in kit form), will make a lot more people interested in the Jordan driver. AFAIK it's something that has been missing up to this point.
I can only comment on the JXR6's imaging WRT my JX92 MLTL set up, which images superbly well down to bass frequencies. At the moment I have the JCR6 in ceramic enclosures with a possible defraction problem at the edges (the sides are proud of the baffle). I'll try something else soon. Ted Jordan mentioned that the narrower driver is probably why a pair image differently from the JX92 - they're less directional, something that the linear array is intended to address. Putting them on a wider baffle might help things. But that's not to say that they image poorly they're still very good.
Used on their own, they do remarkably well to 100Hz but I agree you couldn't use them at high volumes like that. Given that the old JX53 crossed at 500Hz, first order, and had a higher resonant freq, I'd have thought you could have used the JXR6 to 250 or 300Hz without problems. The JX53 went very loud, in the right system (as I found out when I sold the loudspeakers to someone with a more powerful amp than me).
Thanks for the English translation. Missed that.
Used on their own, they do remarkably well to 100Hz but I agree you couldn't use them at high volumes like that. Given that the old JX53 crossed at 500Hz, first order, and had a higher resonant freq, I'd have thought you could have used the JXR6 to 250 or 300Hz without problems. The JX53 went very loud, in the right system (as I found out when I sold the loudspeakers to someone with a more powerful amp than me).
Thanks for the English translation. Missed that.
Hi threaders,
This thread piqued my interest. Would anyone mind coming at this from a "design" perspective?
There are a number of variables that should be considered when designing a loudspeaker. Some of those variables will have an impact upon imaging (width and depth).
One variable is the stop band performance of the woofer. Few small diameter metal coned woofers have a nice and controlled high frequency roll-off. Most "peak" with many "valleys" before finally rolling off.
From the parts list, it is possible that the German design is a complementary second order crossover. If so, and the woofers' stop band performance is less than ideal, then the woofers are going to be very important to the imaging and clarity of the final sound.
In addition, the bad characteristics of high slope crossovers are less troubling at lower frequencies. Indeed, if they help control stop band woofer problems, they can sound better. They also allow for power inputs more consistent with transducer thermal limits than excursion or Xmax limits.
Also, there is some concern about max SPL with a small diameter extended range driver. There are some guides or specifications to allow comparison of max SPL. For example, one spec takes RMS power at the five % distortion rating of a driver at a set distance at Fs or Fo. Combine this max power input with sensitivity and you get a max SPL. Simple answer then to the question, Is this loud enough for me?
To wrap this all up, this is a diy forum. We do not have to take any particular article or design as our own optimum. And I don't know about you, but I believe I can do better than what was referenced here.
Best and all of that,
Mark
This thread piqued my interest. Would anyone mind coming at this from a "design" perspective?
There are a number of variables that should be considered when designing a loudspeaker. Some of those variables will have an impact upon imaging (width and depth).
One variable is the stop band performance of the woofer. Few small diameter metal coned woofers have a nice and controlled high frequency roll-off. Most "peak" with many "valleys" before finally rolling off.
From the parts list, it is possible that the German design is a complementary second order crossover. If so, and the woofers' stop band performance is less than ideal, then the woofers are going to be very important to the imaging and clarity of the final sound.
In addition, the bad characteristics of high slope crossovers are less troubling at lower frequencies. Indeed, if they help control stop band woofer problems, they can sound better. They also allow for power inputs more consistent with transducer thermal limits than excursion or Xmax limits.
Also, there is some concern about max SPL with a small diameter extended range driver. There are some guides or specifications to allow comparison of max SPL. For example, one spec takes RMS power at the five % distortion rating of a driver at a set distance at Fs or Fo. Combine this max power input with sensitivity and you get a max SPL. Simple answer then to the question, Is this loud enough for me?
To wrap this all up, this is a diy forum. We do not have to take any particular article or design as our own optimum. And I don't know about you, but I believe I can do better than what was referenced here.
Best and all of that,
Mark
Dumbass wrote
There are many. One might be that an aspect of diy is doing things yourself instead of just copying or following another's path. Another might be in doing them better. Another might be that there is a limit to speculation and assumption.
For example, it might just be possible that the limited "depth" of image for the new Jordan is partly because of how it is used rather than a "limitation" of the transducer itself. Of course, even if it were, then it is possible to determine this with a high degree of certainty.
If you are going to buy high quality transducers, why stop there? Why not design loudspeakers that maximize transducer quality?
I hope others also have points. Although I also hope that we can avoid an infinite regress of points unless they apply to improved applications of the Jordan transducer. Time will tell.
Best to all out there,
Mark
There are many. One might be that an aspect of diy is doing things yourself instead of just copying or following another's path. Another might be in doing them better. Another might be that there is a limit to speculation and assumption.
For example, it might just be possible that the limited "depth" of image for the new Jordan is partly because of how it is used rather than a "limitation" of the transducer itself. Of course, even if it were, then it is possible to determine this with a high degree of certainty.
If you are going to buy high quality transducers, why stop there? Why not design loudspeakers that maximize transducer quality?
I hope others also have points. Although I also hope that we can avoid an infinite regress of points unless they apply to improved applications of the Jordan transducer. Time will tell.
Best to all out there,
Mark
Hi Mark
My comments on the JXR6 are restricted to one implementation so far and I haven't got round to optimising the cabinet edges yet (a felt baffle would help). I suspect if recessed correctly so the chassis is flush with the baffle, and used on a wider baffle, the image depth would improve to closer to the JX92.
Another point is that it might be psychological - the JX92 is reaching down to 35Hz and I hadn't heard this level of imaging below 100Hz before. I think that helps give the impression of depth because there are more cues to the acoustic venue. I'd have to try rolling off the bass to see.
My comments on the JXR6 are restricted to one implementation so far and I haven't got round to optimising the cabinet edges yet (a felt baffle would help). I suspect if recessed correctly so the chassis is flush with the baffle, and used on a wider baffle, the image depth would improve to closer to the JX92.
Another point is that it might be psychological - the JX92 is reaching down to 35Hz and I hadn't heard this level of imaging below 100Hz before. I think that helps give the impression of depth because there are more cues to the acoustic venue. I'd have to try rolling off the bass to see.
I think how loud you expect the speaker to play, how close you will be listening, and how close the speakers are placed against a back wall are important issues concerning bass reproduction. If someone can come up with a good ported (BR, BLH, MLTL, etc.) that works with the JXr6, then it would really be a good speaker stand alone. I have played with the earlier versions, and the image depth after adding a BSC is really good. The problem is it cannot play loud without running out of bass in this configuration. The high frequency and detail is second to none.
I have tried a design with a two way series XO using the old JX125, and the performance was also good. The project did not evolve further becasue the JX125 was out of production. However, with the design that was tested, the bass when very low and the organs reporduced very well to frequencies you "feel" when placed back close to a wall and port facing the wall. With a series XO, the transition was very good around the XO point (around 450Hz)with little coloration heard in many two way systems. Pianos sound like the same one from the higest notes to the lowest notes. Vocals sound well balanced. Component quality made significant differences.
I have tried a design with a two way series XO using the old JX125, and the performance was also good. The project did not evolve further becasue the JX125 was out of production. However, with the design that was tested, the bass when very low and the organs reporduced very well to frequencies you "feel" when placed back close to a wall and port facing the wall. With a series XO, the transition was very good around the XO point (around 450Hz)with little coloration heard in many two way systems. Pianos sound like the same one from the higest notes to the lowest notes. Vocals sound well balanced. Component quality made significant differences.
For the quality and price of a JXR6HD, you'd be short-changing the driver by using it alone.
We're talking an extremely wideband driver that can produce exceptional detail and dynamics within it's physical limitations. Would you use a Maserati to haul a trailer? Of course you wouldn't.
If you simply do the math concerning what it takes for a driver of that diameter to produce a given SPL at a given frequency, I wonder why you'd want to use it below 150Hz. There are any number of quality 10" to 12" bass drivers that could cover the lower frequencies.
We're talking an extremely wideband driver that can produce exceptional detail and dynamics within it's physical limitations. Would you use a Maserati to haul a trailer? Of course you wouldn't.
If you simply do the math concerning what it takes for a driver of that diameter to produce a given SPL at a given frequency, I wonder why you'd want to use it below 150Hz. There are any number of quality 10" to 12" bass drivers that could cover the lower frequencies.
Hi threaders,
I agree with Colin that psychoacoustics is important in making listening judgements. Simpling reducing the amount of energy in the 60 to 120 Hz range will radically alter the sound of any loudspeaker. If you are used to hearing energy in the range on familiar music, losing it will change all aspects of the sound. It is very hard to hear through it to tell what is going on.
We are also closer to deciding on design variables. We do not, however, know what the x-max SPL limit is for the driver operating at 150 Hz. You can calculate this, but I would like to see that verified with a distortion test at this frequency.
If, as Mark Audio suggests, a sealed enclosure is used to set the driver's low frequency characteristics (say at 150 Hz), then we know that that will produce a second order high pass filter. If we want to protect the Jordan from signals below this frequency, then we will need to add a crossover. If you want a second order filter and integrate it with the enclosure enduced high pass filter, then the acoustic roll-off is now fourth order.
If this allows the Jordan to play loudly enough for the listener's preferences (and we have yet to determine this), then we have one interesting system possibility. There are plate amps available at relatively low cost that have built in adjustable fourth order low pass filters.
Still too many assumptions here. If there is low frequency reductions due to baffle, then these would have to be compensated for. If the Jordan's acoustic output (for a given distortion) is not compromised by a first order crossover, then we can use this extra 6 db per octave to compensate for baffle reductions. Again, I would like to have tests results for baffles and not rely on calculations alone.
Another assumption is the high frequency performance of the woofer. If the acoustic ouptut of the woofer is rising, then to achieve a complementary acoustic crossover, adjustments to the electrical feed will have to be made.
Keep in mind that many performance characteristics for the woofer are going to be dominated by the electrical crossover. Rise time requirements for example are going to be very low. There are a number of drivers in the 6.5 to 8-inch range that have flat responses for several octaves above 150 Hz. Often, when they do breakup and start peaking, they are highly directional. Thus downfiring the woofer will help to control the nasty cone vibration effects.
Just a couple of other things to consider. First, at 150 Hz, the low pass filter is going to be defining the acoustic center of the woofer. At 150 Hz, the acoustic center is going to be almost 2 feet behind the voice coil. Audibility of this offset is limited at low frequencies, but if you want to transiently align the drivers, then a digital delay (with all the limitations it will include) is the only practical way to go.
Biamping at this frequency also allows for easy application of motional feedback for the woofer. Because of the low audibility of acoustic center offsets at and below 150 Hz, and (or) because of using digital delays, then a satelite system with an fairly large amount of physical spacing of woofer and three-inch extended range transducer becomes a possibility.
Lastly, and particularly for Dumbass, it is important to consider design criteria. Since I wrote, we have found out that the 500 Hz crossover of the diy design was based upon some consideration of baffle size. Had little to do with the Jordan. Had more to do with the chosen box design. Although I do wonder why the baffle size only impacts the Jordan and not the bass drivers mounted in the same box. Oh well!
Best,
Mark
I agree with Colin that psychoacoustics is important in making listening judgements. Simpling reducing the amount of energy in the 60 to 120 Hz range will radically alter the sound of any loudspeaker. If you are used to hearing energy in the range on familiar music, losing it will change all aspects of the sound. It is very hard to hear through it to tell what is going on.
We are also closer to deciding on design variables. We do not, however, know what the x-max SPL limit is for the driver operating at 150 Hz. You can calculate this, but I would like to see that verified with a distortion test at this frequency.
If, as Mark Audio suggests, a sealed enclosure is used to set the driver's low frequency characteristics (say at 150 Hz), then we know that that will produce a second order high pass filter. If we want to protect the Jordan from signals below this frequency, then we will need to add a crossover. If you want a second order filter and integrate it with the enclosure enduced high pass filter, then the acoustic roll-off is now fourth order.
If this allows the Jordan to play loudly enough for the listener's preferences (and we have yet to determine this), then we have one interesting system possibility. There are plate amps available at relatively low cost that have built in adjustable fourth order low pass filters.
Still too many assumptions here. If there is low frequency reductions due to baffle, then these would have to be compensated for. If the Jordan's acoustic output (for a given distortion) is not compromised by a first order crossover, then we can use this extra 6 db per octave to compensate for baffle reductions. Again, I would like to have tests results for baffles and not rely on calculations alone.
Another assumption is the high frequency performance of the woofer. If the acoustic ouptut of the woofer is rising, then to achieve a complementary acoustic crossover, adjustments to the electrical feed will have to be made.
Keep in mind that many performance characteristics for the woofer are going to be dominated by the electrical crossover. Rise time requirements for example are going to be very low. There are a number of drivers in the 6.5 to 8-inch range that have flat responses for several octaves above 150 Hz. Often, when they do breakup and start peaking, they are highly directional. Thus downfiring the woofer will help to control the nasty cone vibration effects.
Just a couple of other things to consider. First, at 150 Hz, the low pass filter is going to be defining the acoustic center of the woofer. At 150 Hz, the acoustic center is going to be almost 2 feet behind the voice coil. Audibility of this offset is limited at low frequencies, but if you want to transiently align the drivers, then a digital delay (with all the limitations it will include) is the only practical way to go.
Biamping at this frequency also allows for easy application of motional feedback for the woofer. Because of the low audibility of acoustic center offsets at and below 150 Hz, and (or) because of using digital delays, then a satelite system with an fairly large amount of physical spacing of woofer and three-inch extended range transducer becomes a possibility.
Lastly, and particularly for Dumbass, it is important to consider design criteria. Since I wrote, we have found out that the 500 Hz crossover of the diy design was based upon some consideration of baffle size. Had little to do with the Jordan. Had more to do with the chosen box design. Although I do wonder why the baffle size only impacts the Jordan and not the bass drivers mounted in the same box. Oh well!
Best,
Mark
I'm pleased to see designs appearing for the JXR6, as it is a remarkable little driver. Even used on its own, in a small room and at reasonable volume levels, it serves well.
Regarding baffles, Ted always recommends as wide as possible. His own systems are wall mounted. This gives another interesting use for the JXR6 as it is small enough for several to be integrated into the room and practically disappear. With a suitably hidden bass system, you have access to another psychological trick, where a speaker system sound best when you can't see it.
Regarding baffles, Ted always recommends as wide as possible. His own systems are wall mounted. This gives another interesting use for the JXR6 as it is small enough for several to be integrated into the room and practically disappear. With a suitably hidden bass system, you have access to another psychological trick, where a speaker system sound best when you can't see it.
Colin,
I agree . . . room integration for both sound and decoration are reasons to select a small extended range transducer (like the Jordan). The Jordan is an extended range design and not a full-range design. No three-inch transducer is a full-ranger. I know that people use three-inch transducers as if they were full-rangers, but they are losing too much important musical information by doing so.
I disagree, however, about the projects for the new Jordan being designs. I wish there were some designs. So far, however, that does not seem to be the case.
Mark
I agree . . . room integration for both sound and decoration are reasons to select a small extended range transducer (like the Jordan). The Jordan is an extended range design and not a full-range design. No three-inch transducer is a full-ranger. I know that people use three-inch transducers as if they were full-rangers, but they are losing too much important musical information by doing so.
I disagree, however, about the projects for the new Jordan being designs. I wish there were some designs. So far, however, that does not seem to be the case.
Mark
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