Hi Mattes,
I didn't think that the price diffrence between LB8EX and 21M8EX is so high. 5k USD is definitely to much for me...and like you said the LB8EX seems to be really bargain. You have mentioned that difference betwen LB8 and 21M8EX is small, so I maybe LB8EX will be at least as good as 21M8EX
The SPL chart of LB8EX looks quite good. Slight correction is required between 3-5khz.
I have to check the prices of supravox but it seems that I'm decided for EMS.
You have mentioned that in one of your project you connected LB8 with AE18. I see that you have used AE18 also with 21M8EX. Do you think that electro magnet speaker would be better for bass, or AE18 is enough? Also, if this is not a problem, coud you show your crossover for AE18 dipole?
Regards,
Sebastian
I didn't think that the price diffrence between LB8EX and 21M8EX is so high. 5k USD is definitely to much for me...and like you said the LB8EX seems to be really bargain. You have mentioned that difference betwen LB8 and 21M8EX is small, so I maybe LB8EX will be at least as good as 21M8EX
The SPL chart of LB8EX looks quite good. Slight correction is required between 3-5khz.
I have to check the prices of supravox but it seems that I'm decided for EMS.
You have mentioned that in one of your project you connected LB8 with AE18. I see that you have used AE18 also with 21M8EX. Do you think that electro magnet speaker would be better for bass, or AE18 is enough? Also, if this is not a problem, coud you show your crossover for AE18 dipole?
Regards,
Sebastian
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Hi Sebastian,
yes, 21M8EX is expensive, and I worked hard for it... but OK, as far as the manufacturer and I know, it´s the only pair in Germany.
I had the opportunity to listen to the 21M8 in France also with PM motor, and could compare it to the fieldcoil motor. Again, small difference in quality, considerable price difference, but I choose the fieldcoil motor.
Laws of diminishing returns are severely in force here...
For a start, and to get an impression of those french drivers, you could also start with the PM LB8. It even has 16 Ohm and would match your two bass drivers! I might sell my used pair, should you be interested, just send me a message.
I would think that the difference between PM and fieldcoil would not be that large with the LB 8 either, but this is just an assumption.
I would love to show some measurements, those on the EMS website are, hrrrmmm, very nice, but I don´t have them here, and many have been lost as well in a harddisk crash. However, the LB 8 is relatively easy to tame, the midrange and lower treble mountain could be attenuated, and there´s a geometrical resonance at 9 Khz, from the whizzer cone, which could be treated with the 99-cent-Lowther mod. In the end, you´ll have a good, quick and relatively smooth driver.
Regarding the bass, I like my AE 18, but there are many other ways. Maybe some day, I order a 46M8EX... just have to save a little bit of money. In another discussion, John (the maker of the AE drivers) noted that he couldn´t imagine any advantages with a fieldcoil motor for his drivers...
I´ll respond later to the crossover question! Have to work now...
All the best
Mattes
Mattes
yes, 21M8EX is expensive, and I worked hard for it... but OK, as far as the manufacturer and I know, it´s the only pair in Germany.
I had the opportunity to listen to the 21M8 in France also with PM motor, and could compare it to the fieldcoil motor. Again, small difference in quality, considerable price difference, but I choose the fieldcoil motor.
Laws of diminishing returns are severely in force here...
For a start, and to get an impression of those french drivers, you could also start with the PM LB8. It even has 16 Ohm and would match your two bass drivers! I might sell my used pair, should you be interested, just send me a message.
I would think that the difference between PM and fieldcoil would not be that large with the LB 8 either, but this is just an assumption.
I would love to show some measurements, those on the EMS website are, hrrrmmm, very nice, but I don´t have them here, and many have been lost as well in a harddisk crash. However, the LB 8 is relatively easy to tame, the midrange and lower treble mountain could be attenuated, and there´s a geometrical resonance at 9 Khz, from the whizzer cone, which could be treated with the 99-cent-Lowther mod. In the end, you´ll have a good, quick and relatively smooth driver.
Regarding the bass, I like my AE 18, but there are many other ways. Maybe some day, I order a 46M8EX... just have to save a little bit of money. In another discussion, John (the maker of the AE drivers) noted that he couldn´t imagine any advantages with a fieldcoil motor for his drivers...
I´ll respond later to the crossover question! Have to work now...
All the best
Mattes
Mattes
Hi Mattes,
thank you for information and the offer, however I'm decided on field coil. Probably soon I will be able to hear LB8 and LB12ex at polish distributor demo room. I have to find some free time to go to him, becouse I have ca. 400km to him...
My new tube amplifier will be 8 ohm so I have to build 8ohm speakers.
Regards,
Sebastian
thank you for information and the offer, however I'm decided on field coil. Probably soon I will be able to hear LB8 and LB12ex at polish distributor demo room. I have to find some free time to go to him, becouse I have ca. 400km to him...
My new tube amplifier will be 8 ohm so I have to build 8ohm speakers.
Regards,
Sebastian
Hi Sebastian,
as you´ve asked as well about my bass crossover for AE 18: this is a simple passive filter, series L controls the baffle rise and gives relatively flat response from 30 Hz up, parallel C with a very small R gives the desired slope with -6 dB at 400 Hz. A parallel LCR controls a hump at 180 Hz from the baffle.
Of course I could give you the values, but without having the same driver, baffle and room, they will of course be useless. Many will wonder why I maintain the passive filter, but I tried several (expensive) DSP solutions, until my ears made me come back to passive filters... YMMV, of course.
I have yet to try a balanced version of the bass filter, for the wideband it has worked very well (there was a small discussion in another thread, which has dried out now).
Best regards to Poland, and enjoy the EMSs!
Mattes
as you´ve asked as well about my bass crossover for AE 18: this is a simple passive filter, series L controls the baffle rise and gives relatively flat response from 30 Hz up, parallel C with a very small R gives the desired slope with -6 dB at 400 Hz. A parallel LCR controls a hump at 180 Hz from the baffle.
Of course I could give you the values, but without having the same driver, baffle and room, they will of course be useless. Many will wonder why I maintain the passive filter, but I tried several (expensive) DSP solutions, until my ears made me come back to passive filters... YMMV, of course.
I have yet to try a balanced version of the bass filter, for the wideband it has worked very well (there was a small discussion in another thread, which has dried out now).
Best regards to Poland, and enjoy the EMSs!
Mattes
Hi Mattes,
first of all sorry for late response. I have had some problems at work and had to be focused on it.
My construction will be based on passive filters too. At this moment I will try teslas but if it won't work maybe I will buy AE, becouse a lot of good information about them can be found. I thought to buy 15" Dipole, becouse I thought 18" will be slower, but if I understand you well it is not true. Additionally 18" is on stiff suspension (which I prefere) instead of rubber, which is used in 15" version. Of course there is also AE LO15 which has stiff suspension and is dedicated to open baffle. Of course when I write stiff it really doesn't mean that it is really stiff, I'm just not fan of rubber suspensions
Regards,
Sebastian
first of all sorry for late response. I have had some problems at work and had to be focused on it.
My construction will be based on passive filters too. At this moment I will try teslas but if it won't work maybe I will buy AE, becouse a lot of good information about them can be found. I thought to buy 15" Dipole, becouse I thought 18" will be slower, but if I understand you well it is not true. Additionally 18" is on stiff suspension (which I prefere) instead of rubber, which is used in 15" version. Of course there is also AE LO15 which has stiff suspension and is dedicated to open baffle. Of course when I write stiff it really doesn't mean that it is really stiff, I'm just not fan of rubber suspensions
Regards,
Sebastian
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Hi Mattes,
first of all thank you for asking. At present the situation is completly different then I thoght it will be.
I have changed the concept of my project:
First, I have ordered Acoustic Elegance Dipole18. However due to problems with vendors, John form AE has had some serious delay and I get my drivers 5 months after I placed my order.(pic below)
Secondly,I have changed the mid-high drivers form EMS to Bohlender RD75. I was able to buy completly new pair in the boxes and foils here in Poland (30km away from my home). These are planar magnetic drivers and the high of it is 1,9m (pic below)
I have also corespond via email with John Whittaker, who in 1998 has made wide tests of this drivers and diffferent baffles shape for them. Unfortunately his website ALSR (Acoustic Line Source Research) does not work anymore. Fortunetely, John sent me last version of his webpage which he saved years ago I have to tell you that he is great guy. He has helped me A LOT. Thanks to John now I better understand this drivers and know what to do next Once again great, selfless guy with very wide knowledge.
Thirdly, in the begening of November there was Audio Show here in Warsaw, and I was there with my friend as an exhibitor with GMI30 tubes push-pull amplifier (pic below - btw. I'm not on this photo, these are my friends). That is why I have only checked drivers, but nothing else. I hope I will start works on the speakers in last days of December.
But...I will probably buy EMS drivers next year, I have already plan for the next project
How about you, any changes in the system?
Best regards,
Sebastian
first of all thank you for asking. At present the situation is completly different then I thoght it will be.
I have changed the concept of my project:
First, I have ordered Acoustic Elegance Dipole18. However due to problems with vendors, John form AE has had some serious delay and I get my drivers 5 months after I placed my order.(pic below)
Secondly,I have changed the mid-high drivers form EMS to Bohlender RD75. I was able to buy completly new pair in the boxes and foils here in Poland (30km away from my home). These are planar magnetic drivers and the high of it is 1,9m
(pic below)I have also corespond via email with John Whittaker, who in 1998 has made wide tests of this drivers and diffferent baffles shape for them. Unfortunately his website ALSR (Acoustic Line Source Research) does not work anymore. Fortunetely, John sent me last version of his webpage which he saved years ago
I have to tell you that he is great guy. He has helped me A LOT. Thanks to John now I better understand this drivers and know what to do next Once again great, selfless guy with very wide knowledge.Thirdly, in the begening of November there was Audio Show here in Warsaw, and I was there with my friend as an exhibitor with GMI30 tubes push-pull amplifier (pic below - btw. I'm not on this photo, these are my friends
). That is why I have only checked drivers, but nothing else. I hope I will start works on the speakers in last days of December.But...I will probably buy EMS drivers next year, I have already plan for the next project
How about you, any changes in the system?
Best regards,
Sebastian
Hi Sebastian,
thanks for sharing some interesting photos! I was interested in the RD 75 myself looong ago, but couldn´t afford them that time and have changed plans since then.
For me, not much changes since I´ve finished my speakers (here: Ultimate Open Baffle Gallery) and added an Antipodes streamer to the system. Am really looking forward to listen to my music again next saturday when I´m back home...
Good luck with your new toys, and keep us informed how things are turning out!
All the best
Mattes
thanks for sharing some interesting photos! I was interested in the RD 75 myself looong ago, but couldn´t afford them that time and have changed plans since then.
For me, not much changes since I´ve finished my speakers (here: Ultimate Open Baffle Gallery) and added an Antipodes streamer to the system. Am really looking forward to listen to my music again next saturday when I´m back home...
Good luck with your new toys, and keep us informed how things are turning out!
All the best
Mattes
Hi Mattes,
I saw your speakers in the topic you linked in your previos post...very impresive! I saw one picture that you posted in this topic earlier, but additional pictures do the job
This shows that diy can be much more then the construction available in audio stores.
I would like to ask you about the stainless steel part at the rear of the AE Dipole18 magnet. You have mentioned that "This made an astonishingly large difference, as the relation of masses has doubled."
Does it "only" change in stability (this is important in your construction) or did it changed TSP of the driver? Have you measured it after adding this steel part? Are there any changes in sounding of the driver?
Regards,
Sebastian
I saw your speakers in the topic you linked in your previos post...very impresive! I saw one picture that you posted in this topic earlier, but additional pictures do the job
This shows that diy can be much more then the construction available in audio stores.
I would like to ask you about the stainless steel part at the rear of the AE Dipole18 magnet. You have mentioned that "This made an astonishingly large difference, as the relation of masses has doubled."
Does it "only" change in stability (this is important in your construction) or did it changed TSP of the driver? Have you measured it after adding this steel part? Are there any changes in sounding of the driver?
Regards,
Sebastian
Hi Sebastian,
thanks for the kind words. A construction like this would most possibly be a commercial failure... nothing for the audio stores at all. And that was never the intention - all I had in mind was my personal audio pleasure, and with speakers, I don´t mind the "usual" stuff at all. Seldom I find something interesting, but the reflector series show unusual thinking "out of the box" as well, very impressive.
A few words about the AE Dipole 18:
I´ve chosen the Dipole 18 after I made some OB simulations relying on manufacturer´s data. I use an old AJHorn program for simulating OBs which has proved to be reliable on many occasions. After the D 18 arrived, I had it first in a more simple rigid OB and was astonished to find measured performance to be very good in reach down to 25 Hz, but sensitivity to be nearly 5 dB below simulations. One door closes, another one opens, and the level of the Dipole 18 was nearly that of the corrected FR driver at 16 Khz, so all was fine.
Later, I decided to add a double magnet, which changed the Qts a little bit to 0,65 and brought back nearly 2 dB of useful efficiency without really noticable loss in the very deep bass region. All was fine, the double magnet showed itself as adding a little bit of subjective speed and clarity in the bass region. I have enough power on hand to drive the Dipole 18 to very unsocial levels, luckily I can afford to hear Jonas Hellborgs "Silent life" even late at night at full power with nearly 110 dB peaks in the bass, the Devialets maxing out at app. 1,4 kW into 3 Ohms both channels.
When I started to rig up the flowers, I took the opportunity to measure TSP of my now well-burned Dipole 18 and found that Mms is a lot higher than John states in his data. With the new data entered in the simulation program, the simulation showed precisely what I measured...
And that brings us to the stainless steel parts behind the double magne of the Dipole 18, I call them counterweights, what I think makes sense in a free-swinging arrangement.
With "normal" OBs, some claim that OB mass should be 1000 times Mms, and I´m sure this is a good point and will certainly work. If that much is needed, is a question everyone has to answer for himself... I for one was having resonance problems in moderate heavy and stiff OBs, a reason too to change everything into free-swinging.
That worked fine, but even here a high-mass "counterpoint" for the moving Mms showed advantages. As factor 1000 proved to be a little bit unpractical, I ended up with the 23 Kg counterweights, and a total mass of the bass flower arrangement of a little bit more than 50 Kg, which gives a Mms/total mass factor of around 300.
Even with this reduced factor, handling of the bass flowers is a nightmare... but the sonic results never had me questioning the investment in the stainless steel parts.
So, all in all: the counterweights have not changed the TSP, but the double magnet of course has. Both the double magnet and the counterweight have changed the sound of the AE to the better, to more clarity and more (subjective) speed.
Measuring the AE Dipole 18 is not that easy, as OB bass measurements are generally (it may also be my limited knowledge in measurements...), but I can, should you be interested, post my measured TSP and simulations.
All the best
Mattes
thanks for the kind words. A construction like this would most possibly be a commercial failure... nothing for the audio stores at all. And that was never the intention - all I had in mind was my personal audio pleasure, and with speakers, I don´t mind the "usual" stuff at all. Seldom I find something interesting, but the reflector series show unusual thinking "out of the box" as well, very impressive.
A few words about the AE Dipole 18:
I´ve chosen the Dipole 18 after I made some OB simulations relying on manufacturer´s data. I use an old AJHorn program for simulating OBs which has proved to be reliable on many occasions. After the D 18 arrived, I had it first in a more simple rigid OB and was astonished to find measured performance to be very good in reach down to 25 Hz, but sensitivity to be nearly 5 dB below simulations. One door closes, another one opens, and the level of the Dipole 18 was nearly that of the corrected FR driver at 16 Khz, so all was fine.
Later, I decided to add a double magnet, which changed the Qts a little bit to 0,65 and brought back nearly 2 dB of useful efficiency without really noticable loss in the very deep bass region. All was fine, the double magnet showed itself as adding a little bit of subjective speed and clarity in the bass region. I have enough power on hand to drive the Dipole 18 to very unsocial levels, luckily I can afford to hear Jonas Hellborgs "Silent life" even late at night at full power with nearly 110 dB peaks in the bass, the Devialets maxing out at app. 1,4 kW into 3 Ohms both channels.
When I started to rig up the flowers, I took the opportunity to measure TSP of my now well-burned Dipole 18 and found that Mms is a lot higher than John states in his data. With the new data entered in the simulation program, the simulation showed precisely what I measured...
And that brings us to the stainless steel parts behind the double magne of the Dipole 18, I call them counterweights, what I think makes sense in a free-swinging arrangement.
With "normal" OBs, some claim that OB mass should be 1000 times Mms, and I´m sure this is a good point and will certainly work. If that much is needed, is a question everyone has to answer for himself... I for one was having resonance problems in moderate heavy and stiff OBs, a reason too to change everything into free-swinging.
That worked fine, but even here a high-mass "counterpoint" for the moving Mms showed advantages. As factor 1000 proved to be a little bit unpractical, I ended up with the 23 Kg counterweights, and a total mass of the bass flower arrangement of a little bit more than 50 Kg, which gives a Mms/total mass factor of around 300.
Even with this reduced factor, handling of the bass flowers is a nightmare... but the sonic results never had me questioning the investment in the stainless steel parts.
So, all in all: the counterweights have not changed the TSP, but the double magnet of course has. Both the double magnet and the counterweight have changed the sound of the AE to the better, to more clarity and more (subjective) speed.
Measuring the AE Dipole 18 is not that easy, as OB bass measurements are generally (it may also be my limited knowledge in measurements...), but I can, should you be interested, post my measured TSP and simulations.
All the best
Mattes
Hi Mattes,
first of all sorry for late response, I think there is some problem with information about new post in the topic. I have to chceck if I setup it poroperly on my account.
Thank you for your explenation, its very useful.
I completly agree with you, that commercialy such project would be probably a faliour However...in diy projects we can do whatever we want and it doesn't have to has a financial reason.
I see that you have real power station at home...good for you
I have tried quick connection of AE Dipole 18 with old Isophon P1834 but is was real faliour due to difference in effectiveness of the drivers (and max power?, Isophones are 6W drivers).
When P1834 were playing already quite loud, the Dipole18 at the same time were hardly heard....
Anyway I just have to make a baffles for RD75. I have already calibrate my table saw, so just have to buy material.
I didn't do it last week becouse of holydays and I also worked on my "new" tube tester.
It is only 40 years old and it is like new. It is Kalibr L3-3. It is very good tester but at the same time very complicated, so I have to better understand this beautyful beast
For the first start after so many years I had to use a variac transformer...to avoid blowing up capacitors Fortunately everything went ok. Then few days of warming up and complicated calibration process.
Best regards,
Sebastian
first of all sorry for late response, I think there is some problem with information about new post in the topic. I have to chceck if I setup it poroperly on my account.
Thank you for your explenation, its very useful.
I completly agree with you, that commercialy such project would be probably a faliour
However...in diy projects we can do whatever we want and it doesn't have to has a financial reason.I see that you have real power station at home...good for you
I have tried quick connection of AE Dipole 18 with old Isophon P1834 but is was real faliour due to difference in effectiveness of the drivers (and max power?, Isophones are 6W drivers).
When P1834 were playing already quite loud, the Dipole18 at the same time were hardly heard....
Anyway I just have to make a baffles for RD75. I have already calibrate my table saw, so just have to buy material.
I didn't do it last week becouse of holydays and I also worked on my "new" tube tester.
It is only 40 years old and it is like new. It is Kalibr L3-3. It is very good tester but at the same time very complicated, so I have to better understand this beautyful beast
For the first start after so many years I had to use a variac transformer...to avoid blowing up capacitors
Fortunately everything went ok. Then few days of warming up and complicated calibration process.
Best regards,
Sebastian
Hi Sebastian,
first, all the best for 2020!
Whish I had more knowledge of tubes and testers, as I still have an untested box of tubes, including a pair of EL 156, unused. Ever wanted to make a 15-watt SE amplifier out of them, but that is very far away in the moment.
The Dipole 18, however, I would not trust to really come alive with tubes, despite claims from John. I would feed it with serious power, and would think that for bass alone, one of the better class-D amps should do it, like a hypex or the new purifi (but have never tried both, as I have my Devialets...).
All the best
Mattes
first, all the best for 2020!
Whish I had more knowledge of tubes and testers, as I still have an untested box of tubes, including a pair of EL 156, unused. Ever wanted to make a 15-watt SE amplifier out of them, but that is very far away in the moment.
The Dipole 18, however, I would not trust to really come alive with tubes, despite claims from John. I would feed it with serious power, and would think that for bass alone, one of the better class-D amps should do it, like a hypex or the new purifi (but have never tried both, as I have my Devialets...).
All the best
Mattes
Hi Sebastian,
I use only one amplifier for the full system, since I´m back to passive filters - Devialet D 400. Had many alternatives to choose from, but liked the D 400 best... so my Fertinacoustics is passively filtered, yes.
I have in the past tried a variety of active concepts, some quite expensive, but with this combination, I have always switched back to passive filters after some time. I have enjoyed other active systems in the past (like Maggie 1.6 with RESTEK active crossover and VALVET amplification), so it´s not that I dislike active solutions per se.
A good passive filter is IMHO harder and more expensive to realize than several active approaches, and I´m not going passive to save money at all. I can´t afford doubling up Devialets sadly, but other active solutions were not cheap either...
All the best
Mattes
I use only one amplifier for the full system, since I´m back to passive filters - Devialet D 400. Had many alternatives to choose from, but liked the D 400 best... so my Fertinacoustics is passively filtered, yes.
I have in the past tried a variety of active concepts, some quite expensive, but with this combination, I have always switched back to passive filters after some time. I have enjoyed other active systems in the past (like Maggie 1.6 with RESTEK active crossover and VALVET amplification), so it´s not that I dislike active solutions per se.
A good passive filter is IMHO harder and more expensive to realize than several active approaches, and I´m not going passive to save money at all. I can´t afford doubling up Devialets sadly, but other active solutions were not cheap either...
All the best
Mattes
Attachments
Hi Sebastian,
wishing you best of success with your filter design! For my FR driver, I went with an inductive HP in the end, suited my ears best, but maybe critical with tube amps due to impedance? There are many choices... I needed more than one year to finalize my filters.
No secrets however, if you´re interested in (hand-sketched) schematics, just let me know...
All the best
Mattes
wishing you best of success with your filter design! For my FR driver, I went with an inductive HP in the end, suited my ears best, but maybe critical with tube amps due to impedance? There are many choices... I needed more than one year to finalize my filters.
No secrets however, if you´re interested in (hand-sketched) schematics, just let me know...
All the best
Mattes
Hi Sebastian,
no, not a problem at all. Attached.
It´s a balanced conductive HP filter (if you do such thing then beware of low impedance!), like the first Sonus Faber Extrema. Hope that it might give you a little inspiration - of course all values are only valid for the precise configuration, with the RD 75, something totally different might be needed.
Good luck and all the best
Mattes
no, not a problem at all. Attached.
It´s a balanced conductive HP filter (if you do such thing then beware of low impedance!), like the first Sonus Faber Extrema. Hope that it might give you a little inspiration - of course all values are only valid for the precise configuration, with the RD 75, something totally different might be needed.
Good luck and all the best
Mattes
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