well, it's seems that with OB and with closed cabinet we need to manage the lower frequencies on a different enclosure to obtain extended natural bass sound reproduction, no nasty ported bass or no bass at all. There are another Musical Affairs model with a 12EX + a 15EX....out of my range absolutely, by the way, if I use the 15EX that is way too expensive...but maybe can go with a more common woofer bi-amping, etc.
Anyway, I'm not closed to one or another design. But, at this stage, is a good thing meet someone who has already tried both EMS drivers. There is not too much information on the web. I read a little on a french forum only, but almost all comments are coincident that these drivers are special compared with the fostex or lowthers, even compared to some old school drivers.
Regards
Anyway, I'm not closed to one or another design. But, at this stage, is a good thing meet someone who has already tried both EMS drivers. There is not too much information on the web. I read a little on a french forum only, but almost all comments are coincident that these drivers are special compared with the fostex or lowthers, even compared to some old school drivers.
Regards
Hello Norman, which Phy driver?
how have you solved this lack of bass?
btw, how much bass have you measured on that ob (2' is considerable)?
Regards
Hi Alexsk,
Have you a measurement of your LB12EX in its enclosure (how much average effcienty and Qts choosed) ? How did you deal with the -6dB bafle-step ?
I don't know where the double cone is beginning to radiate.... have you a narrow sweept spot ?
Thanks a lot for your inputs
.....here is in order ...
Yes, I did measure speaker in room.
I run it mostly at 12-13v, in some cases down to 8-9
No BS compenasation. I tried line lavel BS compensation filter and did not like the result.
I don't know where cone begin to radiate, but it not hard to figure from speaker frequency response.
I see no issues with the sweet spot.
Hello, I've never had the chance to hear field coil drivers.
I have enjoyed vintage Alnico extended range, high efficiency drivers from Seas,(94db, augmented with sub and vintage Peerless Alnico paper tweeters), as well as a few 4" modern permanent magnet whizzered and no whizzer "full" rangers.
For full range, my current preference is the Markaudio 12P Alpairs.
None of the above best what I'm using now, a two way, three driver Neo 3, Neo 8, Neo 10 minimal baffle array, augmented and actively crossed over to dual per channel Dayton Audio RSS265 HF-4 10" subwoofers on a u-frame.
While my best full range trumps this in coherence, the planar hybrids easily best the full rangers in resolution, and placement in soundstage imaging.
How big of a jump in natural detail would you rate the field coils over the permanent magnet drivers?
I have enjoyed vintage Alnico extended range, high efficiency drivers from Seas,(94db, augmented with sub and vintage Peerless Alnico paper tweeters), as well as a few 4" modern permanent magnet whizzered and no whizzer "full" rangers.
For full range, my current preference is the Markaudio 12P Alpairs.
None of the above best what I'm using now, a two way, three driver Neo 3, Neo 8, Neo 10 minimal baffle array, augmented and actively crossed over to dual per channel Dayton Audio RSS265 HF-4 10" subwoofers on a u-frame.
While my best full range trumps this in coherence, the planar hybrids easily best the full rangers in resolution, and placement in soundstage imaging.
How big of a jump in natural detail would you rate the field coils over the permanent magnet drivers?
Thanks Alexsk for yours testimonials, there are only two testimonials with this driver at Diyaudio and both are canadian
Had you deduct the Qtc of the finished speaker from your 12-13V (the higher voltage the lower Qtc if I understand well) ?
I didn't see mayself where is the cone break between the two cones from the EMS Speaker datasheet ! I can imagine it is where the 12" beginns to beam ?! But it's funny, we can see the bafle step around 300 hz as the driver is measured with no IE bafle !
I had testimonial from a french who said to me the sound is better when the PS stays switched on (so without the speaker plays all the night/day) because it can takes few hours to have the same result with switching on the PS for immediatly listening to music.
@ MITsound, I can't answer better than Alexsis but many says E M drivers give a very good damping sound with micro resolution, different from Alnico sound ! It's certainly subjective from a scientific point of view...
Planars are good for détails but certainly lack of dynamic when it comes to have a huge dynamic gap at high SPL ? How can an ESL with a dynamic peak of 115 dB spl ? (breaks up of the thin material, natural compression of the low "XMax" of the planar ??, distors ?) ! Even above 300 hz, 500 hz we need SPL peaks ! About détails, more modern modern cone material in a long horn can certainly give better détails than a paper FR above 80/90 hz... at the price of a bigger foot print in our living rooms
)
Sorry here to be off topic, I don't want to polute the thread about this original design EMS + high efficienty tweeter 2Ways
Had you deduct the Qtc of the finished speaker from your 12-13V (the higher voltage the lower Qtc if I understand well) ?
I didn't see mayself where is the cone break between the two cones from the EMS Speaker datasheet ! I can imagine it is where the 12" beginns to beam ?! But it's funny, we can see the bafle step around 300 hz as the driver is measured with no IE bafle !
I had testimonial from a french who said to me the sound is better when the PS stays switched on (so without the speaker plays all the night/day) because it can takes few hours to have the same result with switching on the PS for immediatly listening to music.
@ MITsound, I can't answer better than Alexsis but many says E M drivers give a very good damping sound with micro resolution, different from Alnico sound ! It's certainly subjective from a scientific point of view...
Planars are good for détails but certainly lack of dynamic when it comes to have a huge dynamic gap at high SPL ? How can an ESL with a dynamic peak of 115 dB spl ? (breaks up of the thin material, natural compression of the low "XMax" of the planar ??, distors ?) ! Even above 300 hz, 500 hz we need SPL peaks ! About détails, more modern modern cone material in a long horn can certainly give better détails than a paper FR above 80/90 hz... at the price of a bigger foot print in our living rooms
) Sorry here to be off topic, I don't want to polute the thread about this original design EMS + high efficienty tweeter 2Ways
Hi Sebas,
I had (and still have) the EMS LB8 on OB with an AE 18 Dipole, not exactly the same, but can assure you that the LB 8 is a very good driver, it will not be worse with a fieldcoil motor.
Be prepared to do some response shaping in the midrange.
I finally preferred the FERTIN 21M8EX with fieldcoil motor, but this is pricewise in another league, you pay a lot more for a small difference. I compared the FERTIN drivers with fieldcoil motor and with permanent magnet and preferred the fieldcoil, although it´s even dearer and needs a PSU (I have batteries).
I´m not sure if the EMS 15, which is for sure a very good driver, is the best solution for OB. Reinout in The Netherlands has it in OB and seems to be happy, but I have the feeling that an AE 15 LO or two would be a better match. Personally, I´ve chosen the AE 18, because it goes down to 25 Hz in a modestly sized OB, but of course there´s an efficiency penalty to pay (that´s physics - no way around).
Good luck with your project and all the best
Mattes
Mattes, thank you for reply. At this moment I think I will buy LB8EX and postpone the purchase of LB15EX. Probably I will connect LB8EX with 1 pair of Tesla ARO942 (I have 2 pairs of them). I have also a friend that has already builded field coil driver and he told me that these teslas are just perfect as a base to field coil speaker (mostly due to shape of the cone and very stiff frame).
I have also thought about AE speakers, but at this moment I'm not sure anymore. Where did you buy them? In the US? You were really able to reach 25hz in OB with AE18???
I have also thought about AE speakers, but at this moment I'm not sure anymore. Where did you buy them? In the US? You were really able to reach 25hz in OB with AE18???
Hi Sebas,
do you have any TSP of the Tesla? I´m not sure that these drivers are well suited for OB, but only experiments will tell. If you have two pairs, just make a cheap baffle and try. The real challenge is the filter...
I have bought my AEs directly in the USA, there´s no distributor. And yes, the Dipole 18 goes down to 25 Hz, in-room (26 m²), passive filter. It needs a lot of power, but has no trouble with Jonas Hellborg´s Silent Life, a record which has to be played very very loud...
If you´re in Europe, the AD 1840 is a cheap alternative. Not that deep, but therefore a little bit louder. Compromises in OB bass...
All the best
Mattes
do you have any TSP of the Tesla? I´m not sure that these drivers are well suited for OB, but only experiments will tell. If you have two pairs, just make a cheap baffle and try. The real challenge is the filter...
I have bought my AEs directly in the USA, there´s no distributor. And yes, the Dipole 18 goes down to 25 Hz, in-room (26 m²), passive filter. It needs a lot of power, but has no trouble with Jonas Hellborg´s Silent Life, a record which has to be played very very loud...
If you´re in Europe, the AD 1840 is a cheap alternative. Not that deep, but therefore a little bit louder. Compromises in OB bass...
All the best
Mattes
Good afternoon,
just for clarification: i do not have the EMS LB15EX. I use the (earlier) Fertin 38EX BFA.
There are a lot of similarities between those units (not suprisingly as the come/came from the same production facility) but there are differences as well. Not only obvious parameters as weight (38EX: 18kg; LB15EX: 13,7 kg) and voice coil diameter (38EX: 77 mm; LB15EX:66 mm).
Of more importance:
38EX LB15EX
Fr 30 Hz 22 Hz
Bl 12-20 17-25
Qms 3,84 7,068
Qt 0,37-0,14 0,25-0,13
Xmax 3 mm 7 mm
moving mass 89 gr 58 gr
etc
etc
https://www.diyaudio.com/forums/multi-way/217756-fast-feastrex-d9nf-fertin-38ex.htmlv
I've listened to both units; both great products. And i'm happy with my 38EX; they work very nicely with the Feastrex-units.
Regards,
Reinout
just for clarification: i do not have the EMS LB15EX. I use the (earlier) Fertin 38EX BFA.
There are a lot of similarities between those units (not suprisingly as the come/came from the same production facility) but there are differences as well. Not only obvious parameters as weight (38EX: 18kg; LB15EX: 13,7 kg) and voice coil diameter (38EX: 77 mm; LB15EX:66 mm).
Of more importance:
38EX LB15EX
Fr 30 Hz 22 Hz
Bl 12-20 17-25
Qms 3,84 7,068
Qt 0,37-0,14 0,25-0,13
Xmax 3 mm 7 mm
moving mass 89 gr 58 gr
etc
etc
https://www.diyaudio.com/forums/multi-way/217756-fast-feastrex-d9nf-fertin-38ex.htmlv
I've listened to both units; both great products. And i'm happy with my 38EX; they work very nicely with the Feastrex-units.
Regards,
Reinout
Mattes, I have these teslas in my present OB project (Tesla ARO942 + Isophon P1834 + Aurum Cantus G3Si) and it sound very good, despite Qts is quite low for OB.
Below some old measurement that I have made long time ago. The only issue it that they need transformer to decrease impedance, becouse they are 32ohm.
ReinoutdV, great project and really expensive drivers
At this moment I will almost for sure buy LB8EX (but first I have to hear it), and in the future LB15EX or I will modify teslas and make them field coil drivers.
Below some old measurement that I have made long time ago. The only issue it that they need transformer to decrease impedance, becouse they are 32ohm.
ReinoutdV, great project and really expensive drivers
At this moment I will almost for sure buy LB8EX (but first I have to hear it
), and in the future LB15EX or I will modify teslas and make them field coil drivers.Attachments
Hi Reinout,
sorry for the mistake, didn´t have all your thread in mind...
In fact there are lots of common things with FERTIN, EMS and FERTINACOUSTICS in France, and the two main gentlemen behind are still friends. I once suggested a reunion under one name, but probably was unheard...
By the way: Great system you have done, I will forever envy your turntable and the amps... and your Trentemöller experience made me buy some of his records, too...
All the best and happy listening!
Mattes
sorry for the mistake, didn´t have all your thread in mind...
In fact there are lots of common things with FERTIN, EMS and FERTINACOUSTICS in France, and the two main gentlemen behind are still friends. I once suggested a reunion under one name, but probably was unheard...
By the way: Great system you have done, I will forever envy your turntable and the amps... and your Trentemöller experience made me buy some of his records, too...
All the best and happy listening!
Mattes
Hi Mattes,
No I havn't try 2 per side yet, but it could be good idea. If I connect 2 teslas per side it will give me 16ohm for bass units. Due to higher impedance teslas will play quiter but at the same time 2 drivers per side will give additional 3db and also effectiveness of teslas is 98db where LB8ex is ca.94db...so theoretically this could work
No I havn't try 2 per side yet, but it could be good idea. If I connect 2 teslas per side it will give me 16ohm for bass units. Due to higher impedance teslas will play quiter but at the same time 2 drivers per side will give additional 3db and also effectiveness of teslas is 98db where LB8ex is ca.94db...so theoretically this could work
Hi Sebas,
2 per side will give you at least some more headroom, also for EQ. I doubt that the Teslas will do 98 dB in the lower registers in OB... the lower you go, the higher is the efficiency toll to pay. You´ll have to add rising response due to baffle loss and Qt of 0,3 to your calculations. Baffle size, position and the room are further factors - better is measuring instead of guesses. But, OB is not easy to measure...
However, be prepared for some contour shaping with the LB8, without that I found it a bit too agressive for my ears. But of course, YMMV.
All the best
Mattes
2 per side will give you at least some more headroom, also for EQ. I doubt that the Teslas will do 98 dB in the lower registers in OB... the lower you go, the higher is the efficiency toll to pay. You´ll have to add rising response due to baffle loss and Qt of 0,3 to your calculations. Baffle size, position and the room are further factors - better is measuring instead of guesses. But, OB is not easy to measure...
However, be prepared for some contour shaping with the LB8, without that I found it a bit too agressive for my ears. But of course, YMMV.
All the best
Mattes
Hi Mattes,
you are completely right. In the bottom (till ca. 60hz) it will not give 98dB, however 2 dirvers will give 3dB more then 1, so worth to try
Of course the measurement is a must.
Mattes, can LB8ex really reach 19khz?
Also can you tell me what is the proce of FERTIN 21M8EX? I have sent an email to Fertin Acoustic but without any reply till now.
Regards,
Sebastian
you are completely right. In the bottom (till ca. 60hz) it will not give 98dB, however 2 dirvers will give 3dB more then 1, so worth to try
Of course the measurement is a must.
Mattes, can LB8ex really reach 19khz?
Also can you tell me what is the proce of FERTIN 21M8EX? I have sent an email to Fertin Acoustic but without any reply till now.
Regards,
Sebastian
Hi Sebastian,
if you like to get in contact with Marc Amiard, the owner of FERTINACOUSTICS, I could maybe help, as I have some contact with him. However, do not expect a professionalism as from other manufacturers, this man is more artist than technician... but I liked his drivers more than others, despite the price. The 21M8EX is a bit more than 5000 € per pair, and you´ll have to pick up your pair personally in the south of France.
I myself liked the driver better than the LB8 and bought it. The difference is small, the price difference is very high. But if you compare it with prices of Feastrex or Voxativ drivers, they are in good company.
Compared to these prices, other french manufacturers like EMS and SUPRAVOX offer real bargains...
I doubt that the EMS LB8 will really do 19 Khz, at least not with the same level like, say 1 Khz. This is in common with several fullrange drivers, and in my opinion asks for frequency shaping, to have a relatively even frequency response in the end, but of course others may disagree.
I wouldn´t trust my own humble measurements up to 19 Khz, and sadly, I can´t show them either, as I´m in Africa for work, and won´t return back home before April.
To my ears, the treble of the LB8 was fine, I never felt the need for an extra tweeter. Price-quality relation is much better than the 21M8... but personally I never regretted my decision.
All the best
Mattes
if you like to get in contact with Marc Amiard, the owner of FERTINACOUSTICS, I could maybe help, as I have some contact with him. However, do not expect a professionalism as from other manufacturers, this man is more artist than technician... but I liked his drivers more than others, despite the price. The 21M8EX is a bit more than 5000 € per pair, and you´ll have to pick up your pair personally in the south of France.
I myself liked the driver better than the LB8 and bought it. The difference is small, the price difference is very high. But if you compare it with prices of Feastrex or Voxativ drivers, they are in good company.
Compared to these prices, other french manufacturers like EMS and SUPRAVOX offer real bargains...
I doubt that the EMS LB8 will really do 19 Khz, at least not with the same level like, say 1 Khz. This is in common with several fullrange drivers, and in my opinion asks for frequency shaping, to have a relatively even frequency response in the end, but of course others may disagree.
I wouldn´t trust my own humble measurements up to 19 Khz, and sadly, I can´t show them either, as I´m in Africa for work, and won´t return back home before April.
To my ears, the treble of the LB8 was fine, I never felt the need for an extra tweeter. Price-quality relation is much better than the 21M8... but personally I never regretted my decision.
All the best
Mattes
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