Use the force...!
Scottmoose and 454 Casull,
Good one!
I don't understand how Fertin got sound with no cone either...
Tinitus,
You are correct, when you don't play any bass / low mids through the Manger the tiny (but blindingly fast ) excursions (compression and rarefactions) are free to rise and decay with almost no interference from edge reflections.
I actually have a mathematical proof of this written by a German physicist (internationally recognised) that I am going to post.
Its way above my level but there are a few guys on the forum that will be able to understand it. I would love to get a second opinion. It states "above 300Hz the Manger is accurate..." paraphrasing a tiny bit.
Rudolf,
I don't understand your first point but regarding "how fast does a driver need to be"
I have already covered that in my previous posts.
The 25uS figure has been established using real people in very carefully controlled medical testing.
There have been very interesting studies done with patients in comma's where live music (acoustic guitar in the room) was proven to stimulate certain brain activity. The Manger driver had the same effect when replaying the same music. All other drivers tested caused a spike of intense activity then actually reduced brain activity. The studies are ongoing.
Cheers
Derek.
Scottmoose and 454 Casull,
Good one!
I don't understand how Fertin got sound with no cone either...
Tinitus,
You are correct, when you don't play any bass / low mids through the Manger the tiny (but blindingly fast ) excursions (compression and rarefactions) are free to rise and decay with almost no interference from edge reflections.
I actually have a mathematical proof of this written by a German physicist (internationally recognised) that I am going to post.
Its way above my level but there are a few guys on the forum that will be able to understand it. I would love to get a second opinion. It states "above 300Hz the Manger is accurate..." paraphrasing a tiny bit.
Rudolf,
I don't understand your first point but regarding "how fast does a driver need to be"
I have already covered that in my previous posts.
The 25uS figure has been established using real people in very carefully controlled medical testing.
There have been very interesting studies done with patients in comma's where live music (acoustic guitar in the room) was proven to stimulate certain brain activity. The Manger driver had the same effect when replaying the same music. All other drivers tested caused a spike of intense activity then actually reduced brain activity. The studies are ongoing.
Cheers
Derek.
Hi Guys,
I want to briefly deal with the issue of research into human hearing. It does appear that paragraph 3 in my first post has been forgotten. There are claims being made to support arguments by referring to research into human hearing. However, as yet I don't any correct referencing.
Derek - you say:
"The 25uS figure has been established using real people in very carefully controlled medical testing. There have been very interesting studies done with patients in comma's where live music (acoustic guitar in the room) was proven to stimulate certain brain activity"
So, where is this research? - Please quote the actual science publication, authors (et al), date and time of the research. Also, please check to see if this research has been duplicated by other institutions as part of the verification process. Quote these publications also by referring to the exact published references. This is critical as it gives the other contributors to this thread the opportunity to properly assess the authority and accuracy of your submissions.
Frankly speaking, referring to much of this research has no merit. What's really needed a suitable science institution to run a large scale human trail in controlled conditions to assess the performance of technologies like Manger. Assuming that certain types of performance characteristics as "better" is purely subjective opinion until outcomes are published from authoritative research.
Authoritative research will have the following features:
1 - Large sample size (over 100 humans per trial set). Typically, expect to see authoritative trials using samples of over 1000 human subjects.
2 - Include a test group and a control group.
3 - Controlled test environments and trial methodologies that conform to scientific standards suitable for replication and verification.
4 - Authoritative references to and accurate application of prior research.
5 - Based and/or run from a respected independent research organisation and/or independent educational institution.
Since this thread is going into some depth, it's time to properly reference research when using it to support a submission or argument.
I don't want to disappoint anyone but the more I read , the more I worry. We really do need to be careful about making claims about as to what drivers are doing and how such aspects of their performance relates to human hearing.
I well remember my old faculty head of engineering in a fit of frustration saying : "The real challenge is to get every student applying a minimum of 85% fact, 10% rumour and 5% myth into their work. Regrettably, too many apply 85% myth, 10% rumour and 5% fact!"
All the best,
Mark.
I want to briefly deal with the issue of research into human hearing. It does appear that paragraph 3 in my first post has been forgotten. There are claims being made to support arguments by referring to research into human hearing. However, as yet I don't any correct referencing.
Derek - you say:
"The 25uS figure has been established using real people in very carefully controlled medical testing. There have been very interesting studies done with patients in comma's where live music (acoustic guitar in the room) was proven to stimulate certain brain activity"
So, where is this research? - Please quote the actual science publication, authors (et al), date and time of the research. Also, please check to see if this research has been duplicated by other institutions as part of the verification process. Quote these publications also by referring to the exact published references. This is critical as it gives the other contributors to this thread the opportunity to properly assess the authority and accuracy of your submissions.
Frankly speaking, referring to much of this research has no merit. What's really needed a suitable science institution to run a large scale human trail in controlled conditions to assess the performance of technologies like Manger. Assuming that certain types of performance characteristics as "better" is purely subjective opinion until outcomes are published from authoritative research.
Authoritative research will have the following features:
1 - Large sample size (over 100 humans per trial set). Typically, expect to see authoritative trials using samples of over 1000 human subjects.
2 - Include a test group and a control group.
3 - Controlled test environments and trial methodologies that conform to scientific standards suitable for replication and verification.
4 - Authoritative references to and accurate application of prior research.
5 - Based and/or run from a respected independent research organisation and/or independent educational institution.
Since this thread is going into some depth, it's time to properly reference research when using it to support a submission or argument.
I don't want to disappoint anyone but the more I read , the more I worry. We really do need to be careful about making claims about as to what drivers are doing and how such aspects of their performance relates to human hearing.
I well remember my old faculty head of engineering in a fit of frustration saying : "The real challenge is to get every student applying a minimum of 85% fact, 10% rumour and 5% myth into their work. Regrettably, too many apply 85% myth, 10% rumour and 5% fact!"
All the best,
Mark.
Biology on a new thread.
Hi Mark,
The biology of the human ear and the mechanical / electrical conversion system is a fascinating and complex subject which would require its own thread (or website!!) to even scratch the surface.
Are you an Audiologist by any chance, if you are a new thread will be great!
Rather than divert attention away from the real issues that this thread is dedicated to, I will collate a list of links referencing studies on this subject and list them on a new thread.
THIS existing thread is to explore the topics listed in my opening post.
As you are a driver manufacturer and you have already mentioned that you are aware of new "low mass and ultra low mass " cone / motor technology this is of great interest to all DIY guys.
As you also say you are too short of time to cover in depth subjects I would suggest that your experience as a driver manufacturer will be of great interest to forum members and very quick and easy for you to put down in simple posts.
If you are also able to spend additional time in on a separate thread dedicated to the biology of the human ear so much the better.
Thanks and all the best.
Derek.
Hi Mark,
The biology of the human ear and the mechanical / electrical conversion system is a fascinating and complex subject which would require its own thread (or website!!) to even scratch the surface.
Are you an Audiologist by any chance, if you are a new thread will be great!
Rather than divert attention away from the real issues that this thread is dedicated to, I will collate a list of links referencing studies on this subject and list them on a new thread.
THIS existing thread is to explore the topics listed in my opening post.
As you are a driver manufacturer and you have already mentioned that you are aware of new "low mass and ultra low mass " cone / motor technology this is of great interest to all DIY guys.
As you also say you are too short of time to cover in depth subjects I would suggest that your experience as a driver manufacturer will be of great interest to forum members and very quick and easy for you to put down in simple posts.
If you are also able to spend additional time in on a separate thread dedicated to the biology of the human ear so much the better.
Thanks and all the best.
Derek.
I wouldn't put them on a new thread. As a historian, accurate referencing and quality source material are my stock in trade, and I fail to see why the proper citation of your sources here is supposed to be damaging. They are, or should be, integral to the thread so as to allow an assessment of the validity of any claims being made by any party; that is not diverting attention away from the 'real issues' you refer to: they are an inseparable part of it.
Derek -I mean no offense here at all (genuinely not my way) but could I point out that at present, your posts are reading just a trifle like those of a master addressing his students, which is not in fact the case even if many of us did not have valid concerns over some of the claims being made. While this is a friendly place, and I doubt anyone here is so thin-skinned as to take anything in other than the spirit it was probably intended, the quasi-lecture style /authoritative stance may have the oposite effect to that which you desire, which would be a shame, as the discussion is a potentially interesting one. To cite one minor example, Mark is well aware of the low / ultra low mass technologies around, given that he uses many of them, to tighter tolerances than anyone else in the same market to the best of my knowledge. He doesn't need any instruction on how to post, or where, from any other forum member either, still less suggestions on the value or otherwise of his posts; he has been actively contributing useful information for some months before this thread emerged, as you would discover with a little searching. In the same vein, nobody else here needs similar instruction or permissions (other than from the moderators), assuming they stay within the general forum guidelines.
Derek -I mean no offense here at all (genuinely not my way) but could I point out that at present, your posts are reading just a trifle like those of a master addressing his students, which is not in fact the case even if many of us did not have valid concerns over some of the claims being made. While this is a friendly place, and I doubt anyone here is so thin-skinned as to take anything in other than the spirit it was probably intended, the quasi-lecture style /authoritative stance may have the oposite effect to that which you desire, which would be a shame, as the discussion is a potentially interesting one. To cite one minor example, Mark is well aware of the low / ultra low mass technologies around, given that he uses many of them, to tighter tolerances than anyone else in the same market to the best of my knowledge. He doesn't need any instruction on how to post, or where, from any other forum member either, still less suggestions on the value or otherwise of his posts; he has been actively contributing useful information for some months before this thread emerged, as you would discover with a little searching. In the same vein, nobody else here needs similar instruction or permissions (other than from the moderators), assuming they stay within the general forum guidelines.
Let me throw in some thoughts: IMO the attack of a transient signal is much more important than its decay in a domestic listening environment. Simply because
1.) Instruments and
2.) Listtening rooms
have longer decay times than many mediocre speaker out there.
The MSW is actually built for accurate attack. There are many conventional drivers out there that show a much better decay (usually displayed as waterfall plot) than an MSW.
Regards
Charles
1.) Instruments and
2.) Listtening rooms
have longer decay times than many mediocre speaker out there.
The MSW is actually built for accurate attack. There are many conventional drivers out there that show a much better decay (usually displayed as waterfall plot) than an MSW.
Regards
Charles
Hi,
there have been certain claims made and theories which may be debated.
claim1: The transducer which reproduces an audio signal best is working similar to the mechanism of our ear.
A: I can´t see any reason why this should hold true. I´m convinced that our ear can´t decide how a sound pressure over time is generated, as long as these pressure curves reaching the ear are identical. I don´t think there is asomething like a ´bended wave pressure´ or a ´pistonic pressure´!
claim 2: the dynamic speaker works as a mass-spring system.
A: This is only true for an open voice coil which is not driven by an amp and besides this doesn´t differ to the manger driver. Both systems need a restoring force that provides for a centering of the voicecoil.
claim3: Fast response time of the Manger, because of low mass.
A: The response time is only a matter of the upper bandwidth limits of the transducer, regardless of its mass. Low mass only needs less driving force. The Jordan drivers and others reach a similar upper bandwidth and so a similar response time. Dynamic drivers with high bandwidth often reduce their active membrane area to reach this aim.....nothing different claims the Manger.
claim 4: apart from the Manger all other drivers make failures.
A: So does the Manger. There is no perfect driver.
The Manger has certain virtues as well as certain deficites.
Among the virtues are a fairly good step-response and measures to reduce energy storage within the driver. ESLs aim for the same but with even more success. A well executed ESL outperformes the Manger with regard to response time and clean step response. Which leads to
claim 5: the ultimate driver...
see above...a ´ultimate´ driver but performing worse than a ESL?
I don´t believe it, neither do my ears
..very debatable.
claim6: the Manger transducer works as described in the theoretical papers.
A: If it would...how comes that we can see the 10kHz vibes all over the whole membrane area in the interference pics? They should theoretically be concentrated just around the voicecoil.
If it would.... how comes that the step-response equals that of a conventional dynamic driver (a bit better behaved it is, that´s all!)
Why is the decay in he step response not as fast as the rising flanc, but shows the response of a dampened mass-spring system?
In my opinion the good step response and less energy storage mechanisms make the Manger so special and sounding as it does.
If a conventional ´pistonic´ driver would reach those goals equally well, I´m convinced it would sound the same. If a transducer surpasses those marks, I´m convinced it would sound even better.
That´s why I prefer ESLs (for the midhigh-range...bass is a different matter)
jauu
Calvin
there have been certain claims made and theories which may be debated.
claim1: The transducer which reproduces an audio signal best is working similar to the mechanism of our ear.
A: I can´t see any reason why this should hold true. I´m convinced that our ear can´t decide how a sound pressure over time is generated, as long as these pressure curves reaching the ear are identical. I don´t think there is asomething like a ´bended wave pressure´ or a ´pistonic pressure´!
claim 2: the dynamic speaker works as a mass-spring system.
A: This is only true for an open voice coil which is not driven by an amp and besides this doesn´t differ to the manger driver. Both systems need a restoring force that provides for a centering of the voicecoil.
claim3: Fast response time of the Manger, because of low mass.
A: The response time is only a matter of the upper bandwidth limits of the transducer, regardless of its mass. Low mass only needs less driving force. The Jordan drivers and others reach a similar upper bandwidth and so a similar response time. Dynamic drivers with high bandwidth often reduce their active membrane area to reach this aim.....nothing different claims the Manger.
claim 4: apart from the Manger all other drivers make failures.
A: So does the Manger. There is no perfect driver.
The Manger has certain virtues as well as certain deficites.
Among the virtues are a fairly good step-response and measures to reduce energy storage within the driver. ESLs aim for the same but with even more success. A well executed ESL outperformes the Manger with regard to response time and clean step response. Which leads to
claim 5: the ultimate driver...
see above...a ´ultimate´ driver but performing worse than a ESL?
I don´t believe it, neither do my ears
..very debatable.claim6: the Manger transducer works as described in the theoretical papers.
A: If it would...how comes that we can see the 10kHz vibes all over the whole membrane area in the interference pics? They should theoretically be concentrated just around the voicecoil.
If it would.... how comes that the step-response equals that of a conventional dynamic driver (a bit better behaved it is, that´s all!)
Why is the decay in he step response not as fast as the rising flanc, but shows the response of a dampened mass-spring system?
In my opinion the good step response and less energy storage mechanisms make the Manger so special and sounding as it does.
If a conventional ´pistonic´ driver would reach those goals equally well, I´m convinced it would sound the same. If a transducer surpasses those marks, I´m convinced it would sound even better.
That´s why I prefer ESLs (for the midhigh-range...bass is a different matter)
jauu
Calvin
Biology, new thread.
Hi Scott,
Sorry if I have offended you with my style of posting, I never was very good at PR!
I have been told before I sound arrogant and opinionated and I genuinely try to avoid this, I wish I was as diplomatic as you, and I thank you for being so delicate with your post.
All I am trying to do is open a debate on driver design that encourages people to start exploring the subject in more detail for themselves, then they will come back and post their views. 50 guys Googling and researching will result in a far greater understanding of the subject rather than 1 guy. That assumes the 50 guys all post and share their findings!
Personally I have only 2 objectives in mind with all my posts1) To freely disclose all the lessons (some valuable others not so!) I have learned in 20 years DIY plus 7 years commercial audio.
(2) To learn as much as possible from anyone with experience in driver design, DSP crossovers and open baffle cabinets.
That's it, I am not posting here to win friends and influence people, or to treat the threads as chat rooms!
I want to get in get out fast! i.e. Down load information to anyone interested in my threads and upload information from anyone with experience in driver, DSP crossovers and open baffle cabinets.
Lack of time is a major problem for me.
Much as I would love to sit down and read the 800 pages or more (over 200 on one thread alone !) that I could learn a lot from I just don't have the time. I am no longer in commercial audio so its all just a hobby and a bit of fun.
In this thread (as I have said previously) I want to learn about drivers mechanical functions, look at their strengths and weakness and find out how to maximise the strengths and minimise the weaknesses.
So will you and / or Mark please tell me (or post links to where I can read for myself! ) all about these "new low mass and ultra low mass cone technologies" which can reduce Mms Oscillation?
If you've got it flaunt it, please I am really interested in learning about this!
Regarding the Biology / Mechanics of the ear / brain, as I said in my previous post I am happy to list websites and links on this subject that I have found interesting. But this is way off topic from what I (and most DIY speaker guys) want to learn about here, this is why I will list them on a new thread. This will also show the level of interest in the biology of the ear and we can then compare and see if most DIY guys would like to read about how best to select and use drivers or have a biology lesson!
To compile a balanced and comprehensive record detailing the ongoing research in Audiology is too time consuming for me so you will have to use the links and websites I used to do your own reading.
All the best
Derek.
Hi Scott,
Sorry if I have offended you with my style of posting, I never was very good at PR!
I have been told before I sound arrogant and opinionated and I genuinely try to avoid this, I wish I was as diplomatic as you, and I thank you for being so delicate with your post.
All I am trying to do is open a debate on driver design that encourages people to start exploring the subject in more detail for themselves, then they will come back and post their views. 50 guys Googling and researching will result in a far greater understanding of the subject rather than 1 guy. That assumes the 50 guys all post and share their findings!
Personally I have only 2 objectives in mind with all my posts
1) To freely disclose all the lessons (some valuable others not so!) I have learned in 20 years DIY plus 7 years commercial audio.(2) To learn as much as possible from anyone with experience in driver design, DSP crossovers and open baffle cabinets.
That's it, I am not posting here to win friends and influence people, or to treat the threads as chat rooms!
I want to get in get out fast! i.e. Down load information to anyone interested in my threads and upload information from anyone with experience in driver, DSP crossovers and open baffle cabinets.
Lack of time is a major problem for me.
Much as I would love to sit down and read the 800 pages or more (over 200 on one thread alone !) that I could learn a lot from I just don't have the time. I am no longer in commercial audio so its all just a hobby and a bit of fun.
In this thread (as I have said previously) I want to learn about drivers mechanical functions, look at their strengths and weakness and find out how to maximise the strengths and minimise the weaknesses.
So will you and / or Mark please tell me (or post links to where I can read for myself! ) all about these "new low mass and ultra low mass cone technologies" which can reduce Mms Oscillation?
If you've got it flaunt it, please I am really interested in learning about this!
Regarding the Biology / Mechanics of the ear / brain, as I said in my previous post I am happy to list websites and links on this subject that I have found interesting. But this is way off topic from what I (and most DIY speaker guys) want to learn about here, this is why I will list them on a new thread. This will also show the level of interest in the biology of the ear and we can then compare and see if most DIY guys would like to read about how best to select and use drivers or have a biology lesson!
To compile a balanced and comprehensive record detailing the ongoing research in Audiology is too time consuming for me so you will have to use the links and websites I used to do your own reading.
All the best
Derek.
Calvin asked:
Because it would be a very bad performer then. The ideal step response would be a step as well. I.e. it would consist of an infinite risetime followed by constant pressure.
The decay is simply the result of the lower cutoff frequency. The lower the cutoff frequency the slower the decay while the higher the upper cutoff frequency the faster the rising edge.
In other words: If a driver's step response shows a rising edge that is looking the same as its decay then it would be a very narrow bandwidth driver.
Regards
Charles
Because it would be a very bad performer then. The ideal step response would be a step as well. I.e. it would consist of an infinite risetime followed by constant pressure.
The decay is simply the result of the lower cutoff frequency. The lower the cutoff frequency the slower the decay while the higher the upper cutoff frequency the faster the rising edge.
In other words: If a driver's step response shows a rising edge that is looking the same as its decay then it would be a very narrow bandwidth driver.
Regards
Charles
Step response
Hi Charles and Calvin,
Calvin,
I am not sure I understand your 6 points correctly because on the face of it I disagree with them all!
I do agree with your comment on the Manger sound quality
"Manger so special and sounding as it does." I think we are on the same page with this one!
Charles, I am experimenting with a new co ax driver and I find myself in need of a passive crossover or possibly an active analog crossover. If I private email you the details can you spare some time to help me with it? I dont want to go off topic on my own thread.....!!!!!
Thanks and all the best,
Derek.
Hi Charles and Calvin,
Calvin,
I am not sure I understand your 6 points correctly because on the face of it I disagree with them all!
I do agree with your comment on the Manger sound quality
"Manger so special and sounding as it does." I think we are on the same page with this one!
Charles, I am experimenting with a new co ax driver and I find myself in need of a passive crossover or possibly an active analog crossover. If I private email you the details can you spare some time to help me with it? I dont want to go off topic on my own thread.....!!!!!
Thanks and all the best,
Derek.
Yes you may of course do that. Is there any prestige to gain with it ?
Fun aside: A coaxial is something I always wanted to try as well but I won't find the necessary time soon to bulid something in practice.
What I find interesting are the newer Beyma coaxials with either a neo HF driver or the ones with the shared neo magnet.
Regards
Charles
Fun aside: A coaxial is something I always wanted to try as well but I won't find the necessary time soon to bulid something in practice.
What I find interesting are the newer Beyma coaxials with either a neo HF driver or the ones with the shared neo magnet.
Regards
Charles
Co-ax Coincidence!
Hi Charles,
Well does this mean great minds think alike or the other no so flattering saying....!
I have an on paper design utilising the Beyma 6CX200Nd which is due for UK launch in June or July.
I have some on order and should actually get them in about 4 to 5 weeks.
I will email you the data sheet, its a really sweet little unit.
It wont be in the same league as the TPL 150 or the Manger but its way cheaper to buy and as with most co ax drivers you do get "2 for the price of 1" !!
All the best
Derek.
Hi Charles,
Well does this mean great minds think alike or the other no so flattering saying....!
I have an on paper design utilising the Beyma 6CX200Nd which is due for UK launch in June or July.
I have some on order and should actually get them in about 4 to 5 weeks.
I will email you the data sheet, its a really sweet little unit.
It wont be in the same league as the TPL 150 or the Manger but its way cheaper to buy and as with most co ax drivers you do get "2 for the price of 1" !!
All the best
Derek.
Hi
@phase.
Yes, I know about the step response and the Fs-related decay. But that was what I thought that Overkill tried to imply with "So in summary, it's not how fast a driver starts that counts its how fast it STOPS!". With open voice coil it ´stops´ depending on its fs. The lower Fs the longer the decay. Driven by a signal it simply follows the signal as long as that´s frequency is lower than the bandwidth limit of the driver. The same does the Manger because it needs a restoring force to centre its coils within the airgap. And its in no way quicker or better in doing this than any other driver with the same fs of ~80Hz.
@Overkill
These are the claims as I understand them from the Manger Website and Your own posts.
claim1: post #6 by overkill: "This is exactly the same as our drum strike (assuming we hit the drum in the centre) and this is also how the human ear drum works, (and the Manger driver!!) NONE OF THIS IS PISTONIC!! This is all " Bending Wave " motion."
This implies that any different way of producing ´pressure´ is not natural, hence incorrect.
claim2: post #1 by overkill
claim3: again, the rise time is defined by the upper bandwidth limit of the driver.....nothing different here between Manger and any other driver. The only specialty is, that for a 8" driver the rise time is very short indeed, but still slower than a good modern dome tweeter.
claims 4and 5: post #9 by overkill "ultimate FR-driver".
BtW. I´d expect a ´ultimate´ driver to work as clean as possible, hence low distortion (even if it is debatable if these distortion values might be audible). Values of up to >-40dB already at 90dB@1m are far from ´ultimate´. The CSD-plots are not the best You could expect to see nowadays.
claim6: Text and pics from on the Manger website.
The ´pistonic´ driver doesn´t work pistonic from a given frequency range upwards anymore, right.....but I don´t see on the Manger Pics their claimed behaviour either.
To me the Manger is a ´different´ dynamic driver with certain advantages and certain disadvantages, superior in some points inferior in others. But beeing a dynamic driver its far from ´ultimate´.
jauu
Calvin
@phase.
Yes, I know about the step response and the Fs-related decay. But that was what I thought that Overkill tried to imply with "So in summary, it's not how fast a driver starts that counts its how fast it STOPS!". With open voice coil it ´stops´ depending on its fs. The lower Fs the longer the decay. Driven by a signal it simply follows the signal as long as that´s frequency is lower than the bandwidth limit of the driver. The same does the Manger because it needs a restoring force to centre its coils within the airgap. And its in no way quicker or better in doing this than any other driver with the same fs of ~80Hz.
@Overkill
These are the claims as I understand them from the Manger Website and Your own posts.
claim1: post #6 by overkill: "This is exactly the same as our drum strike (assuming we hit the drum in the centre) and this is also how the human ear drum works, (and the Manger driver!!) NONE OF THIS IS PISTONIC!! This is all " Bending Wave " motion."
This implies that any different way of producing ´pressure´ is not natural, hence incorrect.
claim2: post #1 by overkill
claim3: again, the rise time is defined by the upper bandwidth limit of the driver.....nothing different here between Manger and any other driver. The only specialty is, that for a 8" driver the rise time is very short indeed, but still slower than a good modern dome tweeter.
claims 4and 5: post #9 by overkill "ultimate FR-driver".
BtW. I´d expect a ´ultimate´ driver to work as clean as possible, hence low distortion (even if it is debatable if these distortion values might be audible). Values of up to >-40dB already at 90dB@1m are far from ´ultimate´. The CSD-plots are not the best You could expect to see nowadays.
claim6: Text and pics from on the Manger website.
The ´pistonic´ driver doesn´t work pistonic from a given frequency range upwards anymore, right.....but I don´t see on the Manger Pics their claimed behaviour either.
To me the Manger is a ´different´ dynamic driver with certain advantages and certain disadvantages, superior in some points inferior in others. But beeing a dynamic driver its far from ´ultimate´.
jauu
Calvin
Scottmoose said:You have to use the Force.
It is interesting that you mention that. A theoretically ideal loudspeaker would be a stable "sphere" (or "cylinder") force field in 4 physical dimensions moved about wrt our 3D space. This would appear to us as a massless pulsating sphere (or cylinder)
Still scince fiction at this point thou.
dave
Hi all!
Nice topic if we can keep it clean.
After fiddling around with low q full rangers for the past 30 odd years or so, here is my take on the subject.
Start or stop......is one more important than the other? In this case i would put my money on starting, does not mean that stopping is unimportant though. More important though IMHO is HOW one applies the restoring forse to a "pistonic" drive unit, how is the spring designed? First of all i am convinced that only one spring should be present in the system and it should be as close to the motor as possible, preferrably part of the motor. This means that the edge suspension must not be springy at all if possible, only lossy, and it should not restrict inward or outward movement at all under normal conditions. There have been a number of attempts at this and the best one i have seen so far is the one made by Mr Sano of Exacta in Japan, no longer available unfortunatly. He used a magnetic suspension and used equal gap height, coil length and magnetic "brake", quite clever since the restoring force from the magnetic brake gets weaker proportionally equal to the weakening of the accellerating force from the coil. This was (and usually allways should) paired with quite substantial magnets and very low mass cones and light, deep leather surrounds. Made like this, one gets a "pistonic" drive unit were the motor is in the drivers seat and capable of very good impulse response.
I must say that i was very keen on getting my hands on a pair of Mangers when they where first introduced, and when i did i sold them, they are just not my cup of tea. Maybe it is time to try them again.
NOTE! I am the Scandinavian rep for Feastrex so if you whant to see my post as commercially biased, feel free to do so.
BR,
Anders
Nice topic if we can keep it clean.
After fiddling around with low q full rangers for the past 30 odd years or so, here is my take on the subject.
Start or stop......is one more important than the other? In this case i would put my money on starting, does not mean that stopping is unimportant though. More important though IMHO is HOW one applies the restoring forse to a "pistonic" drive unit, how is the spring designed? First of all i am convinced that only one spring should be present in the system and it should be as close to the motor as possible, preferrably part of the motor. This means that the edge suspension must not be springy at all if possible, only lossy, and it should not restrict inward or outward movement at all under normal conditions. There have been a number of attempts at this and the best one i have seen so far is the one made by Mr Sano of Exacta in Japan, no longer available unfortunatly. He used a magnetic suspension and used equal gap height, coil length and magnetic "brake", quite clever since the restoring force from the magnetic brake gets weaker proportionally equal to the weakening of the accellerating force from the coil. This was (and usually allways should) paired with quite substantial magnets and very low mass cones and light, deep leather surrounds. Made like this, one gets a "pistonic" drive unit were the motor is in the drivers seat and capable of very good impulse response.
I must say that i was very keen on getting my hands on a pair of Mangers when they where first introduced, and when i did i sold them, they are just not my cup of tea. Maybe it is time to try them again.
NOTE! I am the Scandinavian rep for Feastrex so if you whant to see my post as commercially biased, feel free to do so.
BR,
Anders
The way they're carrying on with plasma development (and I'm not thinking speakers per se here) simple versions might not take as long as we think, although still a goodly way off of course.
Interesting nobody has referenced one of my personal favourites (setting practicalites to one side) yet: namely wide BW compression drivers, which are about as good as it gets if used properly. The sheer motor power & diaphram rigidity coupled with minium weight of a good example gives frightening rise & decay times.
Interesting nobody has referenced one of my personal favourites (setting practicalites to one side) yet: namely wide BW compression drivers, which are about as good as it gets if used properly. The sheer motor power & diaphram rigidity coupled with minium weight of a good example gives frightening rise & decay times.
Hi Calvin and Scott,
Calvin,
Thanks for the clarification, we have different views on the operational principals of the Manger, but hey, until Daniela can really explain it 100% on her website the way she can at lectures I think most people will continue (sadly ) pass it by.
One generalisation In my opening post made does need a bit more explanation.
" "So in summary, it's not how fast a driver starts that counts its how fast it STOPS!". "
I should add that the start time (rise time) is still very important, its just MORE important how accurately (fast) the stop (decay time)
is.
Please don't think that I am trying to say the Manger driver is perfect, it is not. I have already posted my interest in a designing new rear basket, new magnet array and a special oval wave / baffle for the Manger.
It is however, in my opinion, the single best driver in current production by a very long way. It still needs one or two conventional drivers to cover the sub 400Hz band.
My mission captain, sorry got carried away there...!
My goal is to find the "most appropriate" conventional drivers for this job. So if any low mass or ultra low mass driver manufacturers are reading this....!
The last couple of points you make are ;
" This implies that any different way of producing ´pressure´ is not natural, hence incorrect. And ;
" again, the rise time is defined by the upper bandwidth limit of the driver.....nothing different here between Manger and any other driver. The only specialty is, that for a 8" driver the rise time is very short indeed, but still slower than a good modern dome tweeter."
The fact that the Mangers Bending wave motion can actually produce faster rise times at 400Hz using its 8 inch flexible membrane than most 1 inch silk dome tweeters can manage at 4KHz says it all I believe.
Please remember I am not here to "sell" the Manger driver!
I am looking for the fastest conventional drivers to blend with the Manger in a DSP controlled fully active tri-amped system.
All the best
Derek.
Calvin,
Thanks for the clarification, we have different views on the operational principals of the Manger, but hey, until Daniela can really explain it 100% on her website the way she can at lectures I think most people will continue (sadly ) pass it by.
One generalisation In my opening post made does need a bit more explanation.
" "So in summary, it's not how fast a driver starts that counts its how fast it STOPS!". "
I should add that the start time (rise time) is still very important, its just MORE important how accurately (fast) the stop (decay time)
is.
Please don't think that I am trying to say the Manger driver is perfect, it is not. I have already posted my interest in a designing new rear basket, new magnet array and a special oval wave / baffle for the Manger.
It is however, in my opinion, the single best driver in current production by a very long way. It still needs one or two conventional drivers to cover the sub 400Hz band.
My mission captain, sorry got carried away there...!
My goal is to find the "most appropriate" conventional drivers for this job. So if any low mass or ultra low mass driver manufacturers are reading this....!
The last couple of points you make are ;
" This implies that any different way of producing ´pressure´ is not natural, hence incorrect. And ;
" again, the rise time is defined by the upper bandwidth limit of the driver.....nothing different here between Manger and any other driver. The only specialty is, that for a 8" driver the rise time is very short indeed, but still slower than a good modern dome tweeter."
The fact that the Mangers Bending wave motion can actually produce faster rise times at 400Hz using its 8 inch flexible membrane than most 1 inch silk dome tweeters can manage at 4KHz says it all I believe.
Please remember I am not here to "sell" the Manger driver!
I am looking for the fastest conventional drivers to blend with the Manger in a DSP controlled fully active tri-amped system.
All the best
Derek.
Feastrex & comp drivers.
Hey Guys goooood points!
Scott,
I have actually never even thought of a compression driver BELOW 400Hz! That is very interesting.
How to get a rigid enough diaphram without using a "ring like a bell" titanium or other metal...?
Beyma use Mylar in some comp drivers, would that work low down?
Personally I would only need to cover the 100Hz to 400Hz band as I have an 18 inch custom bass driver under development for my bass system.
I will have a good think about this and prepare a few questions, thanks for the idea!
Anders,
Yes everything you say makes sense to me, although my money is still on the stop time!
I really like the restoring force being a single, central assembly.
This will be much easier to keep under control and maintain balance.
Also using a much higher ratio of electromagnetic control to mechanical control again makes perfect sense.
How to balance a permanent restoring magnetic force with the fluctuating (with music signal) motor electromagnetic force?
MG where are you....?
All the best
Derek.
Hey Guys goooood points!
Scott,
I have actually never even thought of a compression driver BELOW 400Hz! That is very interesting.
How to get a rigid enough diaphram without using a "ring like a bell" titanium or other metal...?
Beyma use Mylar in some comp drivers, would that work low down?
Personally I would only need to cover the 100Hz to 400Hz band as I have an 18 inch custom bass driver under development for my bass system.
I will have a good think about this and prepare a few questions, thanks for the idea!
Anders,
Yes everything you say makes sense to me, although my money is still on the stop time!
I really like the restoring force being a single, central assembly.
This will be much easier to keep under control and maintain balance.
Also using a much higher ratio of electromagnetic control to mechanical control again makes perfect sense.
How to balance a permanent restoring magnetic force with the fluctuating (with music signal) motor electromagnetic force?
MG where are you....?
All the best
Derek.
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