And then theres modulated Inductance....
Think about it, the further the VC is from rest, then of course the magnetic force will be less.
Preventing the coil leaving the area of linear magnetic flux will prevent this, and BL force is maintained.
Until, large amplitude prevents means the coil leaves the area of uniform field.
Think about it, the further the VC is from rest, then of course the magnetic force will be less.
Preventing the coil leaving the area of linear magnetic flux will prevent this, and BL force is maintained.
Until, large amplitude prevents means the coil leaves the area of uniform field.
Mike7877 - I think I understand what you are trying to get at... However, I think there already exists a driver measurement technology which captures the intent of what you are proposing.
If you look closely at driver reviews which utilize Klippel NFS data, such as Erin's Audio Corner, I think you will understand how this system captures both small signal and large signal performance. It measures how much nonlinearity we get from a driver, with respect to both frequency and drive level.
ScanSpeak Illuminator 18WU4741T-00 7 Inch Midwoofer Review
Here is a link to a review of the scanspeak 18WU Illuminator.
Study this, and see if this kind of measurement technology addresses your concern.
j.
If you look closely at driver reviews which utilize Klippel NFS data, such as Erin's Audio Corner, I think you will understand how this system captures both small signal and large signal performance. It measures how much nonlinearity we get from a driver, with respect to both frequency and drive level.
ScanSpeak Illuminator 18WU4741T-00 7 Inch Midwoofer Review
Here is a link to a review of the scanspeak 18WU Illuminator.
Study this, and see if this kind of measurement technology addresses your concern.
j.
Gap saturation shall come form the magnet system, not the coil. Once you manage to saturate the gap (not easy or cheap), you are home free and a lot of nasty problem disappears.
//
Time domain distortion
According to John Watkinson and Derek Wilson (and Prof, Manger and others) there are serious design failings and unresolved issues with all mass on spring sound transducers ie 99.99% of all loudspeaker drivers.
The attached PDF,s, especially Johns 16 part paper (!) take a a bit of effort to understand but they make valid points based on solid physics and a deep understanding of the "Human Auditory System" (HAS)
My main take away points from reading all of the above are:
(1) All current drivers are 1 or 2 orders of magnitude "too slow" ie the best CSD /time domain performance of the best drivers is still in the 1 to 10 milliseconds. 1,000 th's of a second) Vs the true settling time of real sounds with are measured in microseconds (millionth's of a second)
(2) We can minimise this gross design failing by using high Sd / low Mms / high Bl drivers and sealed box (or no box) loading where ever possible.
(3) Minimising the effects of time domain distortion results in less listner fatigue and a more life like sound.
According to John Watkinson and Derek Wilson (and Prof, Manger and others) there are serious design failings and unresolved issues with all mass on spring sound transducers ie 99.99% of all loudspeaker drivers.
The attached PDF,s, especially Johns 16 part paper (!) take a a bit of effort to understand but they make valid points based on solid physics and a deep understanding of the "Human Auditory System" (HAS)
My main take away points from reading all of the above are:
(1) All current drivers are 1 or 2 orders of magnitude "too slow" ie the best CSD /time domain performance of the best drivers is still in the 1 to 10 milliseconds. 1,000 th's of a second) Vs the true settling time of real sounds with are measured in microseconds (millionth's of a second)
(2) We can minimise this gross design failing by using high Sd / low Mms / high Bl drivers and sealed box (or no box) loading where ever possible.
(3) Minimising the effects of time domain distortion results in less listner fatigue and a more life like sound.
It's a good assumption lol 😉
I've never heard of that design, but it sounds very, very interesting. And promising, more promising than some might expect. I know from experience that the doppler effect on woofers/midwoofers is overstated. I have a good driver with very low distortion within its xmax (ATC SB75-150SL). Running 500-1000hz on top of 10, 20, 30hz results in no distortion within xmax, except for the unavoidable noise of the surround when it starts getting close to xmax. This is 12mm peak to peak, so not a huge distance, but the doppler effect is inaudible. I have perfect pitch, so I'm sensitive. I assume that since it's inaudible to me at that excursion, at least 50mm p-p travel would be possible on a well designed woofer. Not for perfect sound, but near perfect.
Does DC Gold make their woofers the way that patent describes?
I want to keep things as simple as possible - so probably measuring one frequency at two levels. It could end up being 3 or 4 levels if performance between the points varies from driver to driver. The frequency would depend on the cone's diameter, likely wavelength 1.5x circumference of cone + 1/3 surround.
I don't have a measurement mic yet, but I do have two Siglent SDS-1202X-E scopes. One has a problem locking onto things though 🙁
They're two channel, so that's good
I'm open to suggestions!
At this point the discussion is basically about non linear behaviour within the uniform field. Check starting from the second sentence in post 58 for a full explanation.
Thanks for the link, I'll be looking at them this afternoon/evening
I have tweeters (ATC SH25-76s) which have saturated gaps. This problem would still affect it, we're talking about EM saturation. Kind of like what happens if you apply power to a motor's with it's rotor locked in place.
The PDF is a bunch of links. A bunch! lol
It looks interesting and applicable, thanks
Well, the understanding seems not that deep to me, to be honest. Rather a conveniently collected set of assumptions. The science of auditory perception has developed a lot further in the meantime. Discussions about the localization mechanism are quite common round here too, by the way.
Hi Markbak
I have posted a goldmine of relevant on topic peer reviewed data... The papers I posted run to over 300 pages (not including the 22 in paper references) of detailed analysis, comment and conclusions.
I posted at 4.27pm, you "replied" at 6.07pm... So in less than two hours you read, understood and formed an "informed" opinion.... Or you commented on something you hadn't read and therefore cant understand.
This tells me (and most forum members) not to listen to your opinions or advice.
Of course you are now blocked... Life is too short to waste time reading anything you or others who comment without reading, have to say.
I have posted a goldmine of relevant on topic peer reviewed data... The papers I posted run to over 300 pages (not including the 22 in paper references) of detailed analysis, comment and conclusions.
I posted at 4.27pm, you "replied" at 6.07pm... So in less than two hours you read, understood and formed an "informed" opinion.... Or you commented on something you hadn't read and therefore cant understand.
This tells me (and most forum members) not to listen to your opinions or advice.
Of course you are now blocked... Life is too short to waste time reading anything you or others who comment without reading, have to say.
Sorry. I only referred to the understanding about the human hearing. I found no deep understanding there. Did I miss Rayleigh, HRTF, ITD, ILD or IPD?
I won’t argue about the loudspeaker things, I didn’t read them.
I won’t argue about the loudspeaker things, I didn’t read them.
Oh, and I won’t start about air absorbing sound too, or the effect of that to the phase relationship of complex signals. Heck, everyone here with a simple measurement set can check that for him- or herself. Please keep on pursuing dreams.
What was the point you are making?
For the sake of forum discussion, it's more useful to just day what you mean...particularly for the reader stumbling upon this thread.
Your point was?
MCK systems are an order of magnitude too "slow"
I think most educated people would probably agree without feeling the need to cite papers to prove it. Or themselves.
So then the only conclusion is that plasma is the only technology capable of the time domain accuracy, transient capability to match or exceed the ears ability?
Last edited:
H2 Alex - perhaps you could paraphrase this body of research for us... I like reading threads, but I am disinclined to read 300 pages without some assurance that it will be worth my time...
Babb drivers were apparently designed for outdoor/marine apps and the basic design is a wide range 4th order BP with no replaceable parts, so fairly 'bulletproof' overall.
The Babb Lorelei prototypes I have are true full range [low] compression drivers with a 1" Xmax [IIRC, all my data is on two seriously damaged HDs] and in a quick search, not much has survived the net.
IIRC, Alan Babb did some mods for DC Gold, but don't recall him elaborating and the LS6 it became is shrouded in mystery and long gone if it ever was released for sale.
No clue how much of the original internals remains and for all I know the Lorelei is the only model that ever had all of the patent's design details using modern technology such as in testing in his own HT system they could safely handle 400 W with his VC design and with only a ~82? dB eff., it needed it.
As for high excursion distortion, I drove mine with 250 W at a DIY Meet and while we didn't do any measurements they were using a significant amount of the surround's available stroke/20 Hz and couldn't hear any distortion with my face in front of it other than a just audible funky wrinkled paper sound emanating from the surround, so with probably at least half of your 50 mm being silent, betting a [much] longer version wouldn't either.
The docs that survived in the net archives don't have all the pics [illustrations?] and the cutaway is of course quite vague in detail.
The Lorelei Page
Licensing Opportunities
Licensing Opportunities
The Lorelei Normal Size Picture
The Lorelei Double Size Picture
Has anyone ever proven that the transient capabilities of plasma tweeters are really that much better than those of other driver technologies ? While the modulation of the corona discharge can undoubtedly be done with very low inertia I am not that sure that this accounts for the heating and cooling of the air as well. And are both heating and cooling as fast or are we running into problems with asymmetrical slew-rates ? And if the latter is a problem does it also vary with room temperature ?
Regards
Charles
I'd say the air itself isn't able to process transients properly. But what has happened with the simple knowledge that, certainly at mid and high frequencies, the radiation impedance dictates the movement of a cone speaker? That is, apart from breakup modes of the cone itself of course (what is happening all the time to those high Sd and low Mms cones). They ruin the desired transient behavior methinks.
I don't exacly get what you want to say or ask. Do you want to say that the dependancy of cone motion on radiation impedance is ruining the transient behaviour ? Which wouldn't be the case IMO.
Or do you want to say that breakup modes are ruining the transient behaviour ? If yes, then I would definitely agree with you.
Regards
Charles
Or do you want to say that breakup modes are ruining the transient behaviour ? If yes, then I would definitely agree with you.
Regards
Charles
Last edited:
Oh, I see I was a bit cryptic. I meant the latter and also the fact that even relatively heavy cones don't move unless the air or the motor tells them to do so when regarding the so-called resistive frequency range.
Now we could argue about the resonant frequency range (we all have been there before I guess) and/or the transition range between the two and the impact of those to the beloveth transients. I don't think anything new will come out, just like out of the investigations Mike7877 is considering. One thing is for certain, those cone breakups are a story apart. And ETC diagrams, CSD or BD plots tell us that story quite complete.
Now we could argue about the resonant frequency range (we all have been there before I guess) and/or the transition range between the two and the impact of those to the beloveth transients. I don't think anything new will come out, just like out of the investigations Mike7877 is considering. One thing is for certain, those cone breakups are a story apart. And ETC diagrams, CSD or BD plots tell us that story quite complete.