mraudio
Member
Found this on What HiFi...
http://whathifi.com/hi-fi/archive/2008/04/15/news-munich-high-end-show-2008-april-24-28.aspx
http://whathifi.com/hi-fi/archive/2008/04/15/news-munich-high-end-show-2008-april-24-28.aspx
A "little" more info on the CLX
- Thread starter mraudio
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mraudio
Member
Here is a link to a supposed picture of them "under wraps". Scroll about half way down the page.
http://translate.google.com/transla...logan+clx&hl=en&rls=GGLC,GGLC:1969-53,GGLC:en
http://translate.google.com/transla...logan+clx&hl=en&rls=GGLC,GGLC:1969-53,GGLC:en
zaphod
Well-known member
hmmm, no oak finish. darn.
Double diaphragm with triple stators! Wow, I don't think that has ever been tried before! Sort of an electrostatic layer cake! And a dedicated woofer panel too! Now this is what I call some risk-taking! I hope they'll put stats in a new orbit; but even if they bomb, you gotta give them an "A" for "A lotta balls!"
sleepysurf
Well-known member
As their new flagship model, I'm sure they'll eventually offer custom finishes, as with the Summit.
The trickling tidbits of info are starting to tantalize!
Spike
Well-known member
Maybe it's me, but I failed to see the benefit of double diaphram with tripple stators. Why go through all the trouble of having a diaphram directly behind another one? The effective surface to move air remains the same as with 1 diaphram! On the down side, the 2 diaphrams may not be "stretched" at EXACTLY the same "strength" installation wise, introducing undetermined behavior interacting with one another. Phase errors come to mind in this case.
But I'm pretty sure ML has sorted these issues out and I'm eagerly waiting for their technical answers when CLX is unwrapped!
Spike
Hmmm? Interesting. Suppose they were able to have the front diaphragm transmit mids and treble, while the back diaphragm transmits bass waves. Having one behind the other would help ensure phase and time alignment, would it not? Would this even be possible, considering the amount of air that would have to be moved to transmit the bass waves? Probably not.
Or could it be that the rear diaphragm puts out exactly the same frequencies as the front diaphragm, but somehow increases the efficiency of the front diaphragm, allowing it to cover a wider frequency response? It would make sense that even though the effective surface area to move the air is the same, two mylar panels would move air more efficiently and could perhaps move more air as a result. This may be the technology they had to come up with to get really decent bass response from a single panel design.
Anybody got any ideas? Sure is fun to speculate as the info. comes dribbling out.
rhd1953
Well-known member
Increased displacement?
A major limiting factor on the CLS II's is the forward movement of the diaphragm. Adding more signal causes the diaphragm to spark/arc to the stator.
Doubling the diaphragms would allow greater movement at the same voltages (which are below that at which arcing occurs). Bottom line, increased diaphragm movement without increased diaphragm voltage.
Bonus...just a single structure to get doubled CLS's.
A major limiting factor on the CLS II's is the forward movement of the diaphragm. Adding more signal causes the diaphragm to spark/arc to the stator.
Doubling the diaphragms would allow greater movement at the same voltages (which are below that at which arcing occurs). Bottom line, increased diaphragm movement without increased diaphragm voltage.
Bonus...just a single structure to get doubled CLS's.
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amey01
Well-known member
My thoughts exactly!
amey01
Well-known member
The other thing that interests me is that they're calling it a "full-range electrostatic" but also indicating it has a crossover. Any crossover would certainly have to detract from at least *some* of that CLS magic.
Where do you get that from? I see where it says: "Precision Vojtko filtering" but I don't see any reference to a crossover.
I was wondering about all those things too, and then I thought, what if the two diaphragms are have opposing movement, so that the front and rear wave are both in phase!
amey01
Well-known member
Well, if there's a bass panel, and a midrange panel, etc - and there is "filtering', doesn't that imply "crossover"?
I’m pretty sure the triple-stack is for the mid-bass / bass element. The midrange on up is likely a std ESL panel.
Now, there are several ways to take advantage of a dual-diaphragm config. One is to run the diaphragms out of phase, essentially creating a bi-pole, where front and rear wave launches are in-phase. Besides problems with an ‘acoustic suspension’ like vacuum created between the two diaphragms, I just don’t see much value in that arrangement for these frequencies. So it’s pretty likely not that.
Second option, run the two diaphragms in phase and use the added energy of two to provide for longer excursions (for lower frequency extension) and greater SPL ability at low frequencies.
But then this one begs an electrical question: How do you polarize the middle stator when you essentially need it to repel the front diaphragm and attract the rear one at the same time?
Given that a triple stack of stators implies a sealed air chamber between front and rear diaphragms, the trapped air is used as the element that couples the front and back diaphragms. Although that begins to beg questions of ionization and other gas and electrical properties of the trapped element. Maybe they are using some inert gas that is not as eclectically reactive, but has good energy (as in motor force) transfer characteristics (i.e. it ‘compresses’ less readily than regular ‘air’).
But the big conundrum for me is the polarization of the middle stator. Basically, this won’t work. So again, not likely IMHO.
So, what’s the third option? Ah, something really novel (in ESL’s at least).
Again, this is all speculation on my part, but if designing this, I’d go with an idea Dr. Heil introduced decades ago: Don’t ‘push’ the air, ‘squeeze’ it.
If I take two diaphragms and arrange them in such a way that I’m squeezing the air mass between them (vs in front and behind) then I can essentially double my ‘radiating’ surface on a single column of air.
The physical arrangement is likely a 4’ or 5’ long multi-element ESL component placed vertically, but ‘sideways’ next to the high-frequency ESL. This vertical ESL has the two diaphragms radiating left to right and right to left, squeezing a column of air between them. The front wave of this column exits unimpeded from between the triple stack. The rear of that wave is most likely absorbed into a rear chamber (to manage low-freq cancellations), maybe even use a transmission line, or they could try and do dipole bass. Me, it’d trap it.
The answer to the electrical conundrum in option 2 is now fully resolved, as the only way to have a triple-stator ESL work is if the two diaphragms are operating in identical electrical phase. That is, when the center stator is positive, both external stators are negative and both diaphragms go towards the center (squeezing the air between them). Then when the outer stators are positive and the center goes negative, repelling the diaphragms away, they create a ‘sucking’ on the air column between them.
The biggest technical hurdle must have been how to construct a triple stack that has enough air-flow movement relative to stator to diaphragm gaps. Since electrical attraction is reduced logarithmically with distance between stator and diaphragm, the air gap between the two diaphragms and the center stator can’t be too big. But on the other hand, the less air volume and the lower the diaphragm movement allowed, the less SPL and more limited low frequency extension. These dualing challenges must be why it took so long in R&D. the manufacturing aspects must be pretty challenging as well.
One thing is for sure, the voltages applied to the center stator must an order of magnitude larger then the outer ones (to compensate for the large air-gap), I’m wondering whether a step-up transformer alone could do that or if they had to add active circuitry there as well (I’d sure look into that).
If you still are confused, read up on the Tymphany LAT and the Heil air motion transformers. All will be revealed from a theoretical standpoint. The leap is how to translate into the ESL realm. Hopefully, what I’ve written above clears up the approach likely used by ML.
Apologies to my friends at ML if this reveals to many ‘secrets’ but reverse-engineering from little data is a long-held skill of mine
There has to be some form of crossover with two distict frequency divisions between the std panel for the HF and new bass section.
I just hope they support an active configuration as well. Maybe it's the only config?
One of the additional complications of the AMT-like design is what to do with not only the ‘back-wave’ of the squeezed ‘active’ air-column, it’s what to do with the back wave of the two diaphragms. Clearly, these must be absorbed or managed in such a way that they don’t create resistive forces out of proportion with the air-mass between the diaphragms.
One might even envision a complex arrangement that uses transmission line principles to use the ‘back wave’ of the ‘active’ air column to help cancel out the back wave of the diaphragms.
Methinks we’ll see a large box for the mid-bass section of the CLX.
One might even envision a complex arrangement that uses transmission line principles to use the ‘back wave’ of the ‘active’ air column to help cancel out the back wave of the diaphragms.
Methinks we’ll see a large box for the mid-bass section of the CLX.
Perhaps, but not necessarily. It doesn't specifically say that there is a midrange panel and a bass panel, although it seems to be implied. I would also note that in every other ML speaker, they specifically say it has a "Vojtko crossover" but in the information for the CLX it says "Vojtko filtering." I would assume they are making the distinction for a reason, but who knows? If there really is a completely separate panel for the midrange/highs and one for the bass, then you would expect they would have to have a crossover circuit.
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